1996 Dakota Gas Powertrain Diagnostics

TABLE OF CONTENTS
1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 1.1 1.2 2.0 3.0 SYSTEM COVERAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 SIX-STEP TROUBLESHOOTING PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . .1

IDENTIFICATION OF SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 SYSTEM DESCRIPTION AND FUNCTIONAL OPERATION . . . . . . . . . . . . . . . . . . . . . .1 3.1 3.2 GENERAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 JTEC CONTROLLER AND OPERATING MODES . . . . . . . . . . . . . . . . . . . . . . . .1 3.2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 3.2.2 Hardware Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 3.2.3 Software Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 3.2.4 Spark Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 3.2.5 Fuel Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 3.2.6 On Board Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 3.2.7 Transmission Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 3.2.8 Other Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 3.2.9 PCM Operating Modes (Gasoline & Eng.) . . . . . . . . . . . . . . . . . . . . . . . . .6 3.2.10 PCM Operating Modes (Diesel) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 3.2.11 Non-Monitored Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 DIAGNOSTIC TROUBLE CODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 3.3.1 Hard Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 3.3.2 Intermittent Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 3.3.3 Reset Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 3.3.4 Handling No Trouble Code Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 USING THE DRB. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 DRB ERROR MESSAGES AND BLANK SCREEN. . . . . . . . . . . . . . . . . . . . . . .12 3.5.1 DRB Does Not Power Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12 3.5.2 Display Is Not Visible . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

3.3

3.4 3.5

4.0

SYSTEM COMPONENT LOCATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 POWERTRAIN CONTROL MODULE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 CONTROLS & SOLENOIDS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 DATA LINK CONNECTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29 SENSORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30 FUEL SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48 RELAYS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51 SWITCHES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58 LAMPS & INDICATORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62

5.0

DISCLAIMERS, SAFETY, WARNINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66 5.1 5.2 DISCLAIMERS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66 SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66 5.2.1 Technician Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66 5.2.2 Vehicle Preparation for Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67 5.2.3 Servicing Sub-Assemblies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67 5.2.4 DRBIII Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67 WARNINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 5.3.1 Vehicle Damage Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 5.3.2 Road Testing a Complaint Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
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5.3

TABLE OF CONTENTS - Continued
7.0 DIAGNOSTIC INFORMATION AND PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . .69 7.1 GENERAL TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69 TROUBLE CODE TESTS DTC TEST CHECKING THE SYSTEM FOR DIAGNOSTIC TROUBLE CODES (DTCs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70 TROUBLE CODE TESTS TC-1A REPAIRING - NO CAM SIGNAL AT PCM . . . . . . . . . . . . . . . . . . . . . . .74 TC-5A REPAIRING - CHARGING SYSTEM VOLTAGE TOO LOW . . . . . . . . .84 TC-6A REPAIRING - CHARGING SYSTEM VOLTAGE TOO HIGH . . . . . . . . .88 TC-10A REPAIRING - AUTO SHUTDOWN RELAY CONTROL CIRCUIT . . . . .96 TC-11A REPAIRING - GENERATOR FIELD NOT SWITCHING PROPERLY. .100 TC-12A REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104 TC-14A REPAIRING - RAD FAN CONTROL RELAY CIRCUIT . . . . . . . . . . . .122 TC-15A REPAIRING - SPEED CONTROL SOLENOID CIRCUITS OR SPEED CONTROL POWER RELAY CIRCUITS . . . . . . . . . . . . . . . . . . . . . . .126 TC-16A REPAIRING - A/C CLUTCH RELAY CIRCUIT. . . . . . . . . . . . . . . . . . .136 TC-17A REPAIRING - EGR SOLENOID CIRCUIT . . . . . . . . . . . . . . . . . . . . . .140 TC-18A REPAIRING - EVAP PURGE SOLENOID CIRCUIT . . . . . . . . . . . . . .144 TC-19A REPAIRING - INJECTOR #3 CONTROL CIRCUIT . . . . . . . . . . . . . . .150 TC-20A REPAIRING - INJECTOR #2 CONTROL CIRCUIT . . . . . . . . . . . . . . .158 TC-21A REPAIRING - INJECTOR CONTROL CIRCUITS . . . . . . . . . . . . . . . .166 TC-25A REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS. . . . . . . . . . .178 TC-26A REPAIRING - THROTTLE POSITION SENSOR VOLTAGE LOW. . . .194 TC-27A REPAIRING - THROTTLE POSITION SENSOR VOLTAGE HIGH . . .200 TC-30A REPAIRING - ECT SENSOR VOLTAGE TOO LOW . . . . . . . . . . . . . .206 TC-31A REPAIRING - ECT SENSOR VOLTAGE TOO HIGH. . . . . . . . . . . . . .210 TC-35A REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL. . . . . . . . . . .214 TC-36A REPAIRING - MAP SENSOR VOLTAGE TOO LOW - NO 5 VOLTS TO MAP SENSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226 TC-37A REPAIRING - MAP SENSOR VOLTAGE TOO HIGH . . . . . . . . . . . . .232 TC-39A REPAIRING - NO CHANGE IN MAP FROM START TO RUN . . . . . .238 TC-40A REPAIRING - NO CRANK REFERENCE SIGNAL AT PCM . . . . . . . .242 TC-41A REPAIRING - IGNITION COIL #3 PRIMARY CIRCUIT . . . . . . . . . . . .248 TC-42A REPAIRING - IGNITION COIL #2 PRIMARY CIRCUIT . . . . . . . . . . . .252 TC-43A REPAIRING - IGNITION COIL #1 PRIMARY CIRCUIT . . . . . . . . . . . .256 TC-44A REPAIRING - NO ASD RELAY OUTPUT VOLTAGE AT PCM. . . . . . .264 TC-48A REPAIRING - PCM FAILURE SRI MILE NOT STORED . . . . . . . . . . .272 TC-49A REPAIRING - EEPROM WRITE DENIED . . . . . . . . . . . . . . . . . . . . . .273 TC-50A REPAIRING - TRANS 3-4 SOLENOID/TRANS RELAY CKTS . . . . . .274 TC-55A REPAIRING - INJECTOR #9 CONTROL CIRCUIT . . . . . . . . . . . . . . .290 TC-56A REPAIRING - INJECTOR #10 CONTROL CIRCUIT . . . . . . . . . . . . . .292 TC-57A REPAIRING - INTAKE AIR TEMP SENSOR VOLTAGE LOW . . . . . . .294 TC-58A REPAIRING - INTAKE AIR TEMP SENSOR VOLTAGE HIGH . . . . . .298 TC-61A REPAIRING - INJECTOR #4 CONTROL CIRCUIT . . . . . . . . . . . . . . .302 TC-62A REPAIRING - 1/1 O2 SENSOR SHORTED TO VOLTAGE . . . . . . . . .310 TC-66A REPAIRING - 2/1 O2 SENSOR SHORTED TO VOLTAGE . . . . . . . . .314 TC-69A REPAIRING - INJECTOR #5 CONTROL CIRCUIT . . . . . . . . . . . . . . .318 TC-70A REPAIRING - INJECTOR #6 CONTROL CIRCUIT . . . . . . . . . . . . . . .324 TC-74A REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO LOW . . . . . .330
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TABLE OF CONTENTS - Continued
TC-75A TC-76A TC-77A TC-79A TC-80A TC-87A TC-94A TC-95A TC-98A TC-99A TC-101A TC-102A TC-103A TC-104A TC-105A TC-106A TC-107A TC-112A TC-113A TC-114A TC-115A TC-118A TC-119A TC-120A TC-121A TC-122A TC-124A TC-126A TC-128A TC-132A TC-138A TC-140A TC-141A TC-142A TC-144A TC-147A TC-148A TC-149A TC-150A TC-151A TC-153A TC-155A TC-156A TC-157A TC-160A TC-161A TC-162A TC-164A REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO HIGH . . . . . .334 REPAIRING - IGNITION COIL #4 PRIMARY CIRCUIT . . . . . . . . . . . .342 REPAIRING - IGNITION COIL #5 PRIMARY CIRCUIT . . . . . . . . . . . .346 REPAIRING - INJECTOR #7 CONTROL CIRCUIT . . . . . . . . . . . . . . .350 REPAIRING - INJECTOR #8 CONTROL CIRCUIT . . . . . . . . . . . . . . .360 REPAIRING - SPEED CONTROL SWITCH ALWAYS LOW . . . . . . . .366 REPAIRING - CNG TEMP SENSOR VOLTAGE TOO LOW . . . . . . . .370 REPAIRING - CNG TEMP SENSOR VOLTAGE TOO HIGH . . . . . . . .374 REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO HIGH . . .378 REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO LOW . . .384 REPAIRING - FUEL PUMP (SYSTEM) RELAY CONTROL CIRCUIT .390 REPAIRING - 1/1 O2 SENSOR SLOW RESPONSE . . . . . . . . . . . . .398 REPAIRING - 1/1 O2 SENSOR HEATER FAILURE . . . . . . . . . . . . . .400 REPAIRING - 1/2 O2 SENSOR SLOW RESPONSE . . . . . . . . . . . . .404 REPAIRING - 1/2 O2 SENSOR HEATER FAILURE . . . . . . . . . . . . . .406 REPAIRING - MULTIPLE CYLINDER MIS-FIRE . . . . . . . . . . . . . . . . .410 REPAIRING - CYLINDER #1, #2, #3, #4, #5, #6, #7, OR #8 MISFIRE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .418 REPAIRING - CATALIYTIC CONVERTER EFFICIENCY FAILURE. . .422 REPAIRING - EVAP PURGE FLOW MONITOR FAILURE . . . . . . . . .424 REPAIRING - P/N SWITCH STUCK IN PARK OR IN GEAR . . . . . . .432 REPAIRING - POWER STEERING SWITCH FAILURE . . . . . . . . . . .438 REPAIRING - FUEL SYSTEM 1/1 RICH . . . . . . . . . . . . . . . . . . . . . . .444 REPAIRING - FUEL SYSTEM 1/1 LEAN. . . . . . . . . . . . . . . . . . . . . . .448 REPAIRING - FUEL SYSTEM 2/1 RICH . . . . . . . . . . . . . . . . . . . . . . .452 REPAIRING - FUEL SYSTEM 2/1 LEAN. . . . . . . . . . . . . . . . . . . . . . .456 REPAIRING - 2/1 O2 SENSOR SLOW RESPONSE . . . . . . . . . . . . .460 REPAIRING - 2/1 O2 SENSOR HEATER FAILURE . . . . . . . . . . . . . .462 REPAIRING - 1/2 O2 SENSOR SHORTED TO VOLTAGE . . . . . . . . .466 REPAIRING - CLOSED LOOP TEMP NOT REACHED . . . . . . . . . . .470 REPAIRING - TPS VOLTAGE DOES NOT AGREE WITH MAP . . . . .472 REPAIRING - TARGET IDLE NOT REACHED . . . . . . . . . . . . . . . . . .478 REPAIRING - EGR SYSTEM FAILURE . . . . . . . . . . . . . . . . . . . . . . .484 REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .488 REPAIRING - GOVERNOR PRESSURE ABOVE 3 PSI IN GEAR WITH 0 MPH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .498 REPAIRING - 1/3 O2 SENSOR SHORTED TO GROUND . . . . . . . . .506 REPAIRING - 1/3 O2 SENSOR SHORTED TO VOLTAGE . . . . . . . . .510 REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP . . . .514 REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO LOW . . . .524 REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO HIGH . . . .528 REPAIRING - FUEL LEVEL UNIT NO CHANGE OVER MILES . . . . .534 REPAIRING - BATTERY TEMP SENSOR VOLTAGE TOO LOW/TOO HIGH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .538 REPAIRING - 1/1 O2 SENSOR SHORTED TO GROUND . . . . . . . . .544 REPAIRING - 1/2 O2 SENSOR SHORTED TO GROUND . . . . . . . . .548 REPAIRING - INTERMITTENT LOSS OF CMP OR CKP . . . . . . . . . .552 REPAIRING - EVAP LEAK MONITOR SMALL LEAK DETECTED . . .566 REPAIRING - EVAP LEAK MONITOR LARGE LEAK DETECTED . . .570 REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS. . . .574 REPAIRNG - TRANS TEMP SENSOR, NO RISE AFTER START . . .582

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TC-165A TC-166A TC-167A TC-168A TC-169A TC-171A TC-173A TC-181A TC-183A TC-184A TC-186A TC-187A TC-188A TC-189A REPAIRING - 3-4 SHIFT SOLENOID, NO RPM DROP 3-4 SHIFT. . .586 REPAIRING - LOW OUTPUT SPEED SENSOR RPM, ABOVE 15 MPH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .592 REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO LOW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .596 REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .600 REPAIRING - GOVERNOR PRESSURE SENSOR OFFSET VOLTS TOO LOW OR HIGH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .614 REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .620 REPAIRING - TRANS 12 VOLT SUPPLY RELAY CNTRL CIRCUIT . .636 REPAIRING - 2/1 O2 SENSOR SHORTED TO GROUND . . . . . . . . .640 REPAIRING - LEAK DETECTION PUMP SOLENOID CIRCUIT . . . . .644 REPAIRING - LEAK DETECTION PUMP SW OR MECHANICAL FAULT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .648 REPAIRING - MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT . . . . . . .652 REPAIRING - EVAP LEAK MONITOR PINCHED HOSE . . . . . . . . . .654 REPAIRING - O/D SWITCH PRESSED (LO) MORE THAN 5 MIN. . .658 REPAIRING - 1/3 O2 SENSOR HEATER FAILURE . . . . . . . . . . . . . .662

NO TROUBLE CODE TESTS NTC-1A NO TROUBLE CODE TEST MENU . . . . . . . . . . . . . . . . . . . . . . . . . .666 NTC-2A CHECKING SECONDARY IGNITION AND TIMING . . . . . . . . . . . . . .668 NTC-3A CHECKING FUEL PRESSURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .670 NTC-4A CHECKING COOLANT SENSOR CALIBRATION . . . . . . . . . . . . . . . .676 NTC-5A CHECKING THROTTLE POSITION SENSOR . . . . . . . . . . . . . . . . . .678 NTC-6A CHECKING MAP SENSOR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .680 NTC-7A CHECKING OXYGEN SENSOR SWITCHING . . . . . . . . . . . . . . . . . .682 NTC-8A CHECKING THE OXYGEN SENSOR HEATER . . . . . . . . . . . . . . . . .688 NTC-9A CHECKING IDLE AIR CONTROL MOTOR . . . . . . . . . . . . . . . . . . . . .690 NTC-10A CHECKING THE PARK/NEUTRAL POSITION SWITCH. . . . . . . . . . .698 NTC-11A CHECKING THE PCM POWER AND GROUND CIRCUITS . . . . . . . .702 NTC-12A CHECKING THE EVAP SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . .704 NTC-13A CHECKING EGR SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .708 NTC-14A CHECKING THE ENGINE VACUUM . . . . . . . . . . . . . . . . . . . . . . . . .714 NTC-15A CHECKING THE INTAKE AIR TEMP SENSOR . . . . . . . . . . . . . . . . .716 NTC-16A CHECKING MINIMUM AIR FLOW . . . . . . . . . . . . . . . . . . . . . . . . . . .718 NTC-17A CHECKING THE AIR INTAKE HEATER #1. . . . . . . . . . . . . . . . . . . . .720 NTC-18A CHECKING THE AIR INTAKE HEATER #2. . . . . . . . . . . . . . . . . . . . .726 NTC-19A CHECKING THE FUEL HEATER . . . . . . . . . . . . . . . . . . . . . . . . . . . .732 NTC-20A CHECKING THE WAIT-TO-START LAMP. . . . . . . . . . . . . . . . . . . . . .736 NTC-21A CHECKING THE WATER-IN-FUEL LAMP & SENSOR . . . . . . . . . . . .740 NTC-22A CHECKING THE ENGINE MECHANICAL SYSTEMS. . . . . . . . . . . . .748 SPEED CONTROL TESTS SC-1A CHECKING THE SPEED SC-2A CHECKING THE SPEED SC-3A CHECKING THE SPEED SC-4A CHECKING THE SPEED SC-5A CHECKING THE SPEED CHARGING TESTS
iv

CONTROL OPERATION CONTROL OPERATION CONTROL OPERATION CONTROL OPERATION CONTROL OPERATION

. . . . . . . . . . . . . .750 . . . . . . . . . . . . . .762 . . . . . . . . . . . . . .764 . . . . . . . . . . . . . .770 . . . . . . . . . . . . . .772

TABLE OF CONTENTS - Continued
CH-1A CHARGING SYSTEM NO CODE TEST . . . . . . . . . . . . . . . . . . . . . . .774 NO START TESTS NS-SEL NO START SELECTION MENU . . . . . . . . . . . . . . . . . . . . . . . . . . . . .780 NS-1A QUALIFYING A NO START CONDITION . . . . . . . . . . . . . . . . . . . . . .782 NS-2A CHECKING FUEL SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .792 NS-3A CHECKING THE MECHANICAL SYSTEM . . . . . . . . . . . . . . . . . . . . .794 NS-4A REPAIRING LOW FUEL PRESSURE . . . . . . . . . . . . . . . . . . . . . . . . .796 NS-5A CHECKING THE FUEL PUMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .798 NS-6A REPAIRING A ЉNO RESPONSEЉ CONDITION . . . . . . . . . . . . . . . . . .802 NS-7A CHECKING IDLE AIR CONTROL MOTOR . . . . . . . . . . . . . . . . . . . . .826 NS-8A REPAIRING A START AND STALL CONDITION. . . . . . . . . . . . . . . . .840 NS-9A REPAIRING A NO CRANK CONDITION . . . . . . . . . . . . . . . . . . . . . . .842 NS-10A QUALIFYING A NO START CONDITION (8.0 L ONLY) . . . . . . . . . . .852 NS-11A CHECKING THE FUEL SYSTEM (CNG) . . . . . . . . . . . . . . . . . . . . . .858 NS-12A CHECKING THE FUEL RELAYS AND SOLENOIDS . . . . . . . . . . . . .872 NS-13A CHECKING FUEL PRESSURE LOSS . . . . . . . . . . . . . . . . . . . . . . . .876 NS-14A CHECKING THE FUEL HEATER RELAY . . . . . . . . . . . . . . . . . . . . . .878 NS-15A CHECKING THE FUEL SHUTDOWN RELAY AND SOLENOID (DIESEL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .882 VERIFICATION TESTS VER-1A NO START VERIFICATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .888 VER-2A ROAD TEST VERIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .889 VER-3A CHARGING VERIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .890 VER-4A SPEED CONTROL VERIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . .891 VER-5A ROAD TEST FOR OBDII TROUBLE CODES . . . . . . . . . . . . . . . . . . .892 8.0 9.0 MAINTENANCE AND SERVICE INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . .893 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .893 9.1 9.2 FUEL FUEL 9.2.1 9.2.2 SYSTEM RELEASE PROCEDURE (GASOLINE). . . . . . . . . . . . . . . . . .893 SYSTEM PRESSURE RELEASE PROCEDURE (CNG) . . . . . . . . . . . .893 Fuel Line Pressure Release Procedure . . . . . . . . . . . . . . . . . . . . . . . . .893 Fuel Cylinder Pressure Release Procedure . . . . . . . . . . . . . . . . . . . . . .894

10.0

SCHEMATIC DIAGRAMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .895 10.1 10.2 10.3 10.4 10.5 10.6 10.7 10.8 10.9 10.10 10.11 10.12 1996 1996 1996 1996 1996 1996 1996 1996 1996 1996 1996 1996 DODGE 2.5L JTEC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .895 JEEP XJ 2.5L JTEC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .896 JEEP XJ 4.0L JTEC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .897 JEEP ZJ 4.0L JTEC SYSTEM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .898 DODGE 3.9L JTEC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .899 DODGE 5.2/5.9L JTEC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .900 JEEP ZJ 5.2L JTEC SYSTEM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .901 DODGE 5.9L-HD JTEC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .902 DODGE 5.9L CUMMINS DIESEL JTEC SYSTEM. . . . . . . . . . . . . . . . . .903 DODGE 8.0L V10-MD SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .904 DODGE 8.0L V10-HD SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .905 DODGE 5.2L CNG, AB, AN, AND BR SYSTEM . . . . . . . . . . . . . . . . . . .906

11.0

REQUIRED TOOLS AND EQUIPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .907
v

TABLE OF CONTENTS - Continued
12.0 GLOSSARY OF TERMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .907 12.1 BODY CODES DEFINED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .908

vi

1.0

INTRODUCTION

The procedures contained in this manual include all the specifications, instructions, and graphics needed to diagnose powertrain control module (PCM) problems; they are no start, diagnostic trouble code, and no trouble code problems for the PCM. The diagnostics in this manual are based on the trouble condition or symptom being present at the time of diagnosis. When repairs are required, refer to the appropriate volume of the service manual for the proper removal and repair procedure. Diagnostic procedures change every year. New diagnostic systems may be added; carryover systems may be enhanced. READ THE GENERAL INFORMATION SECTIONS IN THIS MANUAL BEFORE TRYING TO DIAGNOSE A VEHICLE TROUBLE CODE. It is recommended that you review the entire manual to become familiar with new or revised diagnostic procedures. This book reflects many suggested changes from readers of past issues. After using this book, if you have any comments or recommendations, please fill out the form at the back of the book and mail it back to us.

G E N E R A L I N F O R M A T I O N

1.1

System Coverage

This diagnostic procedures manual covers all 1996 Jeep and Dodge Truck vehicles with a new PCM (JTEC Engine and 42RX Transmission Controller).

1.2

Six-Step Troubleshooting Procedure

Diagnosis of the powertrain control module PCM is done in six basic steps:
• • • • • •

verification of complaint verification of any related symptoms symptom analysis problem isolation repair of isolated problem verification of proper operation

2.0

IDENTIFICATION OF SYSTEM

The powertrain control module PCM monitors and controls the engine, fuel system, ignition system, and automatic transmission.

3.0 3.1

SYSTEM DESCRIPTION AND FUNCTIONAL OPERATION General Description

The Jeep and Dodge Truck engine and Auto Transmission systems have the latest in technical advances. The on-board OBDII diagnostics incorporated with the PCM controller are intended to assist the field technician in repairing vehicle problems by the quickest means.

3.2 3.2.1

JTEC Controller and Operating Modes Overview

The Jeep-Truck PCM features a multi-processor environment (one 16 bit microcomputer, two 8 bit microcomputers) allowing parallel processing of time critical operations. Dedication of one 8 bit processor (K4) to spark control and the other 8 bit processor (D3) to fuel control allows increases in throughput and reduced software complexity in the 16 bit microcomputer (Z2). The result is
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increased capability in the Z2 to handle overall strategy implementation, OBDII, and other computation-intensive processes. This approach allows control of ten cylinder engines in running excess of 6,500 RPM.

3.2.2

Hardware Architecture

The design of the PCM can be broken up into about eight major sections. The main microcontroller, a Motorola MC68HC16Z2, is attached to a 256k byte memory device (flash memory) which is programmed after manufacture of the module. (This memory can be reprogrammed at the factory or at a dealership. The MC68HC11D3 and MC68HC11K4 microcomputers have memories which are permanently programmed during their manufacture, and therefore cannot be reprogrammed.) The microcomputers communicate over a bus which allows for rapid transmission of high priority messages. The Z2 executes the primary powertrain control strategy; transmits fuel and spark requirements to the D3 and K4; communicates with outside devices; and processes 14 analog inputs and about half of the one bit inputs and outputs. The D3 microcomputer controls fuel injector timing pulses and a small number of one bit inputs and outputs. The K4 controls spark timing pulses, processes 8 analog inputs and a number of one bit inputs and outputs. Other major sections of the PCM design include the power supply, input conditioning circuits, output driver circuits, serial communication interface circuits, and a device which controls ignition coil currents.

3.2.3

Software Architecture

The 68HC16Z2 microcontroller is the main computing unit of the PCM. The 68HC11D3 and K4 microcontrollers control fuel and spark respectively. They handle the critical timing requirements of their tasks, communicating with the Z2 using high level commands. The Z2 operating system is the heart of the software and was written expressly for this PCM. Every 500 microseconds the Z2 interrupts what it is doing to perform periodic tasks such as updating sensor inputs values and checking for the occurrence of a crank position pulse. If this pulse is observed, a program known as the decision maker is executed and performs high priority tasks such as fuel and spark calculations, and RPM processing. Low priority tasks (i.e. OBDII processing, SCI and CCD communications) are executed during the time between crank pulses. The Z2 software is divided into a main operating strategy and three separate calibration areas. The main strategy contains information specific to the various engines and transmissions supported by this PCM. Once installed, the information contained in this area is fixed for a given engine and transmission. Changes to this data, if required, can be performed only by computer programming personnel. The calibration areas (engine, transmission and OBDII) contain information relating to emissions, fuel economy and driveability and can be altered directly by calibration personnel.

3.2.4

Spark Control

The K4 microcomputer controls the generation and timing of spark pulses. The spark advance and dwell characteristics are determined by: engine speed, throttle position, MAP, coolant temperature, barometric air pressure, air temperature, and vehicle speed.

3.2.5

Fuel Control

The PCM controls the air/fuel ratio of the engine by varying fuel injector on time. Mass air flow is calculated using the speed density method using engine speed, manifold absolute pressure, and air charge temperature. Different fuel calculation strategies are used dependent on the operational state of the engine. During crank mode, a prime shot fuel pulse is delivered followed by fuel pulses determined by a
2

crank time strategy. Cold engine operation is determined via an open loop strategy until the O2 sensors have reached operating temperature. At this point, the strategy enters a closed loop mode where fuel requirements are based upon the state of the O2 sensors, engine speed, MAP, throttle position, air temperature, battery voltage, and coolant temperature. Additional factors can influence fuel pulse width. Asynchronous acceleration enrichment is a technique whereby the duration of injector ‘‘on’’ time can be increased for injectors already firing, providing improved acceleration response. The D3 microcomputer controls fuel injector timing in response to high level commands from the Z2 microcomputer. Injector timing with respect to engine position is determined by the D3 and is transparent to the Z2.

G E N E R A L I N F O R M A T I O N

3.2.6

On Board Diagnostics

The PCM has been programmed to monitor many different circuits of the fuel injection system. This monitoring is called ‘‘on-board diagnosis.’’ Certain criteria, or ‘‘arming conditions,’’ must be met for a trouble code to be entered into the PCM memory. The criteria may be a range of: engine rpm, engine temperature, and/or input voltage to the PCM. If a problem is sensed with a monitored circuit, and all of the criteria or arming conditions are met, a trouble code will be stored in the PCM. It is possible that a trouble code for a monitored circuit may not be entered into the PCM memory even though a malfunction has occurred. This may happen because one of the trouble code criteria (arming conditions) has not been met. The PCM compares input signal voltages from each input device with specifications (the established high and low limits of the range) that are programmed into it for that device. If the input voltage is not within specifications and other trouble code criteria (arming conditions) are met, a trouble code will be stored in the PCM memory. The On Board Diagnostics have evolved to the second Generation of Diagnostics referred to as OBDII. These OBDII Diagnostics control the functions necessary to meet the requirements of California OBDII and Federal OBD regulations. These requirements specify the inclusion of a malfunction indicator light (MIL) located on the instrument panel for all 1994 and subsequent model-year passenger cars, light duty trucks, and medium-duty vehicles. The purpose of the MIL is to inform the vehicle operator in the event of malfunction of any powertrain components which can affect emissions and which provide input to, or receive output from, the engine controller module. Control of OBDII functions is separated into two areas: the Task Manager and the Comprehensive Component Manager. Task Manager The Task Manager controls the execution of some component/systems tests, control of MIL illumination, storage of fault codes, and storage of vehicle data at time of fault detection (freeze frame). This routine performs the following monitoring requirements: Fuel System Monitoring Misfire Detection EGR System Monitor Oxygen Sensor Upstream Heater Monitor Oxygen Sensor Upstream Monitor Evaporative System Monitor Catalyst Monitor

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Purge Flow Monitor 02 Heater Downstream Monitor 02 Sensor Downstream Monitor Another function of the task manager is control of the Disable Tables. These tables are used to discontinue testing when a condition specified in the tables are met. Testing of a component or system is disabled if a fault or failure occurs which would render the test useless. (For example, the ‘‘Catalyst Monitor’’ test will not be run unless the ‘‘O2 Sensor’’ test has passed.) Comprehensive Component Manager The Comprehensive Component Manager controls the testing of all powertrain components/ systems which can affect emissions and were not otherwise tested by the Task Manager. This routine is organized into three areas: D3 and K4 CIRCUIT CHECKS − Performed on sensor inputs connected to the D3 and K4 to determine out-of-range or high/flow input conditions. Performed on outputs to check for open/short conditions. The components tested are: IAC Open/Short Circuit Generator Field TCC Solenoid Fan Relay A/C Relay Air Switch / Shift Lock Solenoid Transmission Relay Output ASD Relay Fuel Pump Relay EVAP Purge Solenoid EGR Solenoid Ignition Coils (1 thru 5) Injector Failure (1-10) Z2 CIRCUIT CHECKS − Performed on sensor inputs connected to the Z2 to determine out-of-range or high/low input conditions. Performed on outputs to check for open/short conditions. The components tested are: MAP Sensor Voltage (high/low) Intake Air Temperature Sensor Voltage (high/low) Coolant Temperature Sensor Voltage (high/low) Throttle Position Sensor Voltage (high/low) MAP Sensor 5 Volt Supply Check CNG Pressure Sensor Voltage (high/low) CNG Temperature Sensor Voltage (high/low) Battery Temperature Sensor Voltage (high/low) Fuel Level Sensor Voltage (high/low) Transmission Temperature Sensor Voltage (high/low) Governor Pressure Sensor Voltage (high/low) Governor Pressure Solenoid (open/short) ASD Relay Voltage (out of range) Battery Voltage (too high) Overdrive Override Switch (fault) Leak Detection Pump Solenoid (open/short) 3/4 Shift Solenoid (open/short) Speed Control Vac and Vent Solenoids (open/short)

4

FUNCTIONALITY/RATIONALITY CHECKS − These tests determine if a component is working correctly through methods other than voltage limit tests and open/short tests. Solenoids in this section are checked for proper operation (functionality) and sensors are checked for meaningful output values (rationality). The components/systems checked are: Cam Sensor Pulses Present Crank Sensor Pulses Present MAP Sensor Output in Range Coolant Temperature in Range Throttle Position Sensor in Range Vehicle Speed Sensor Output Correct Park/Neutral Switch Working Fuel Level Sensor Output Correct Transmission Temperature Sensor Output Correct Transmission Governor Pressure in Range Output Shaft Speed Sensor Output Correct AIS Motor Working Lock-up Solenoid Working 3/4 Shift Solenoid Working Governor Pressure Solenoid Working O2 Sensor 1/1 Output Voltage Low O2 Sensor 1/2 Output Voltage Low O2 Sensor 2/1 Output Voltage Low O2 Sensor 2/2 Output Voltage Low Charging System Working Power Steering Switch Working Thermostat Working O2 Sensor 1/1 (open circuit or high voltage) O2 Sensor 1/2 (open circuit or high voltage) O2 Sensor 2/1 (open circuit or high voltage) O2 Sensor 1/2 (open circuit or high voltage)

G E N E R A L I N F O R M A T I O N

3.2.7

Transmission Control

The PCM operation includes control of 3 and 4 speed automatic transmissions utilizing electronic governor pressure control, eliminating the need for a separate transmission controller. Transmission control is achieved through regulation of governor pressure using a variable force solenoid valve. (Valve position is controlled by pulse width modulation. Torque convertor lock-up and overdrive solenoids are also controlled by the PCM, as are the transmission protection relay and dashboard overdrive lamp. PCM inputs affecting transmission operation include the throttle position sensor, output shaft speed sensor, vehicle speed sensor, engine speed sensor, brake switch, cruise control switches, ignition, overdrive on/off switch and sump fluid temperature thermistor. Electronic Governor Pressure Control Regulation of governor pressure by enables control of WOT shift points to within +/- 50 RPM resulting in improved shift quality (as opposed to control to within +/- 300 RPM in transmission utilizing mechanical governors). The elimination of the mechanical governor resulted in a physically smaller and lighter package. Torque calculation can be used to determine when upshifting is advantageous. Anti-Hunt Shift Strategy This strategy was added in order to maintain fuel economy over a variety of load conditions. This technique allows for relatively early upshift in mid-range throttle settings under light load conditions, resulting in improved fuel economy. Under heavier loading, shifts are delayed to prevent upshifting into a condition where insufficient torque is available to maintain vehicle speed, resulting in downshift/upshift cycling.
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G E N E R A L I N F O R M A T I O N

Sump Pump Temperature Sensing A themistor is attached to the lock-up solenoid and submerged in the sump fluid. The sump fluid temperature is a factor in the calculation of WOT shift strategy, low temperature shift compensation, sump temperature limiting strategy, overdrive strategy, torque converter clutch strategy, and governor pressure transducer calibration.

3.2.8

Other Controls

Cruise Control The PCM controls vehicle speed by operation of the speed control servo vacuum and vent solenoids. Energizing the vacuum solenoid applies vacuum to the servo to increase throttle position. Operation of the vent solenoid slowly releases the vacuum allowing throttle position to decrease. A special dump solenoid allows immediate release of throttle position caused by braking, cruise control turn off, or ignition key off. Exhaust Gas Recirculation The PCM controls a solenoid which enables/disables EGR. Control of exhaust gas recirculation (using exhaust gas pressure to modulate the vacuum supply to the EGR valve) is enabled only after the engine has warmed. Fuel Vapor Recovery System (Duty Cycle Purge Control) Duty Cycle Purge is a system that feeds fuel gases from the purge canister and gasoline tank into the throttle body for mixing with incoming air. Metering of the gases is performed by duty cycling the purge solenoid by the PCM. The system is disabled during wide open throttle conditions and while the engine is below a specified coolant temperature. When engine temperature becomes greater than a calibrated parameter, duty cycle purge is delayed for a calibrated time. Once purge delay is over, purge will be ramped in to soften the effect of dumping additional fuel into the engine. The PCM provides a modulated 5 hz signal (at closed throttle) or 10 hz signal (at open throttle) to control this system. Modulation of the signal is based upon a calculated air flow (based upon known fuel flow through the injector at a given pulsewidth and RPM) and is adjusted to compensate for changes in flow due to varying engine vacuum.

3.2.9

PCM Operating Modes (Gasoline & Eng.)

As Input signals to the PCM change, the PCM adjusts its response to output devices. For example, the PCM must calculate a different injector pulse width and ignition timing for idle than it does for wide open throttle. There are several different modes of operation that determine how the PCM responds to the various input signals. There are two types of engine control operation: open loop and closed loop. In open loop operation, the PCM receives input signals and responds according to preset programming. Inputs from the heated oxygen sensors are not monitored. In closed loop operation, the PCM monitors the inputs from the heated oxygen sensors. This input indicates to the PCM whether or not the calculated injector pulse width results in the ideal air-fuel ratio of 14.7 parts air to 1 part fuel. By monitoring the exhaust oxygen content through the oxygen sensor, the PCM can fine tune injector pulse width. Fine tuning injector pulse width allows the PCM to achieve optimum fuel economy combined with low emissions. The engine start-up (crank), engine warm-up, and wide open throttle modes are open loop modes. Under most operating conditions, the acceleration, deceleration, and cruise modes, with the engine at operating temperature, are closed loop modes.

6

Ignition Switch On (Engine Off) Mode When the ignition switch activates the fuel injection system, the following actions occur: 1. The PCM determines atmospheric air pressure form the MAP sensor input to determine basic fuel strategy. 2. The PCM monitors the engine coolant temperature sensor and throttle position sensor input. The PCM modifies fuel strategy based on this input. When the Ignition key is in the ‘‘on’’ position and the engine is not running (zero rpm), the auto shutdown relay and fuel pump relay are not energized. Therefore, voltage is not supplied to the fuel pump, ignition coil, and fuel injectors. Engine Start-Up Mode – This is an open loop mode. The following actions occur when the starter motor is engaged: 1. The auto shutdown and fuel pump relays are energized. If the PCM does not receive the camshaft and crankshaft signals within approximately one second, these relays are de-energized. 2. The PCM energizes all fuel injectors until it determines crankshaft position from the camshaft and crankshaft signals. The PCM determines crankshaft position within one engine revolution. After the crankshaft position has been determined, the PCM energizes the fuel injectors in sequences. The PCM adjusts the injector pulse width and synchronizes the fuel injectors by controlling the fuel injectors’ ground paths. Once the auto shutdown and fuel pump relays have been energized, the PCM determines the fuel injector pulse width based on the following: – – – – – engine coolant temperature manifold absolute pressure intake air temperature engine revolutions throttle position

G E N E R A L I N F O R M A T I O N

The PCM determines the spark advance based on the following: – – – – – – engine coolant temperature crankshaft position camshaft position intake air temperature manifold absolute pressure throttle position

Engine Warm-Up Mode – This is an open loop mode. The PCM adjusts injector pulse width and controls injector synchronization by controlling the fuel injectors’ ground paths. The PCM adjusts ignition timing and engine idle speed. The PCM adjusts the idle speed by controlling the idle air control motor. Cruise or Idle Mode – When the engine is at normal operating temperature, this is a closed loop mode. During certain idle conditions, the PCM may enter into a variable idle speed strategy. At this time, the PCM adjusts engine speed based on the following inputs: – – – throttle position battery voltage engine coolant temperature

Acceleration Mode – This is a closed loop mode. The PCM recognizes an increase in throttle position and a decrease in Manifold Vacuum as engine load increases. In response, the PCM increases the injector pulse width to meet the increased load.
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G E N E R A L I N F O R M A T I O N

Deceleration Mode – This is a closed loop mode. The PCM recognizes a decrease in throttle position and an increase in Manifold Vacuum as engine load decreases. In response, the PCM decreases the injector pulse width to meet the decreased load. Wide Open Throttle Mode – This is an open loop mode. The throttle position sensor notifies the PCM of a wide open throttle condition. The PCM adjusts injector pulse width to supply a predetermined amount of additional fuel.

3.2.10

PCM Operating Modes (Diesel)

As input signals to the powertrain control module (PCM) change, the PCM adjusts its response to output devices. There are several different modes of operation that determine how the PCM responds to the various input signals. In all modes, the wait-to-start lamp will flash if an open circuit is detected in the intake air temperature sensor circuit. Ignition Switch On (Engine Off) Mode When the ignition switch is in the ‘‘on’’ position, the following actions occur: 1. When the PCM receives an ignition sense input, it powers up. Battery voltage is supplied through the battery voltage input. 2. The wait-to-start, water-in-fuel, check engine and transmission temperature (auto trans only) lamps are turned on by the PCM for at least 2 seconds as a bulb test. 3. The PCM monitors the intake air temperature signal. If the intake air temperature is below a predetermined temperature, the PCM will start the air intake heater preheat cycle. The PCM will energize the intake heaters by grounding the air intake heater relays. The PCM will turn the wait-to-start lamp on until the preheat cycle is over. If the PCM receives a crank signal before the preheat cycle is over, the preheat cycle will be aborted. 4. The PCM will turn on the water-in-fuel lamp if a signal is received from the water-in-fuel sensor. NOTE: If the water-in-fuel lamp remains illuminated after the 2-second bulb check, the vehicle should not be started until the fuel filter has been drained and primed. Engine Start-Up Mode When the ignition key is held in the ‘‘start’’ position, the following occurs: 1. The PCM receives the crank signal input from the crank position sensor. 2. The air intake heaters are not energized during cranking. 3. The PCM monitors engine speed and when the engine speed is above 375 rpm, the PCM determines that the engine is running. 4. If the PCM receives a crank signal before the preheat cycle is over, the heaters will be de-energized. However, the post-heat cycle will begin if the engine speed is above 375 rpm. Engine Warm-Up Mode 1. The PCM may start the air intake heater post-heat cycle depending on intake air temperature. If manifold air temperature was at 66°F or less when the ignition was turned on, the cycle is started. 2. If the transmission temperature sensor determines it is below 59°F, the automatic transmission will not be allowed to enter overdrive. 3. If the transmission temperature sensor determines it is below 69°F, the transmission’s torque converter clutch will not be allowed to engage. 4. The PCM will turn on the water-in-fuel lamp if a signal is received from the water-in-fuel sensor.
8

Cruise or Idle Mode During cruising speed, the following inputs are received by the PCM: 1. The PCM monitors intake manifold air temperature through the intake air temperature sensor. 2. The intake air heater post-heat cycle will be completed, if it is not already over. 3. The vehicle speed, crank position, and throttle position sensors are used to control the transmission overdrive and torque converter clutch operation. 4. If the transmission temperature sensor determines it is below 59°F or above 275°F, the automatic transmission will not be allowed to enter overdrive. If the transmission is in overdrive when the transmission temperature is above 275°F, the transmission will downshift and not upshift again until the transmission temperature drops to 240°F. 5. The water in-fuel sensor signal is used by the PCM to turn on the water-in-fuel lamp, if water is sensed in the fuel. Acceleration Mode When there is an abrupt demand for increased engine output and vehicle acceleration, the following occurs: 1. The vehicle speed, crank position, and throttle position sensors are used to control transmission overdrive and torque converter clutch operation. 2. If the transmission temperature sensor determines it is below 69°F, the transmission’s torque converter clutch will not be allowed to engage. 3. If the transmission temperature sensor determines it is below 59°F or above 275°F, the automatic transmission will not be allowed to enter overdrive. If the transmission is in overdrive when the transmission temperature is above 275°F, the transmission will downshift and not upshift again until the transmission temperature drops to 240°F. 4. If the speed control system resume/accelerate function is being used, the PCM will only allow the vehicle to accelerate at a predetermined rate. If a speed control has been set and the resume/accelerate button is momentarily pushed in, the PCM will increase vehicle speed by two miles per hour. 5. The PCM will disable the speed control when: – the brakes are applied – the clutch is disengaged (manual transmission) – the gear selector is shifted to neutral (automatic transmission) – the speed control off switch is activated Deceleration Mode During deceleration, the following inputs are received by the PCM: 1. The vehicle speed, crank position, and throttle position sensors are used to control transmission overdrive and torque converter clutch operation. 2. The torque converter clutch will disengage, if the brakes are applied. 3. If the transmission temperature sensor determines it is below 59° or above 275°F, the automatic transmission will not be allowed to enter overdrive. If the transmission is in overdrive when the transmission temperature is above 275°F, the transmission will downshift and not upshift again until the transmission temperature drops to 240°F.

G E N E R A L I N F O R M A T I O N

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G E N E R A L I N F O R M A T I O N

4. The PCM will disable the speed control when: – the brakes are applied – the clutch is disengaged (manual transmission) – the gear selector is shifted to neutral (automatic transmission) – the speed control off switch is activated Ignition Switch Off Mode When the ignition switch is turned to the ‘‘off’’ position, the PCM still receives battery voltage through the battery input. Battery voltage is needed to keep PCM memory alive. The Memory stores trouble codes and the throttle position sensor value from the previous key-on.

3.2.11

Non-Monitored Circuits

The PCM does not monitor the following circuits, systems, and conditions even though they could have malfunctions that result in driveability problems. A diagnostic code may not be displayed for the following conditions. However, problems with these systems may cause a diagnostic code to be displayed for other systems. For example, a fuel pressure problem will not register a diagnostic code directly, but could cause a rich or lean condition. This could cause an oxygen sensor, fuel system, or misfire monitor trouble code to be stored in the PCM. Engine Timing – The PCM cannot detect an incorrectly indexed timing chain, camshaft sprocket, or crankshaft sprocket. The PCM also cannot detect an incorrectly indexed distributor.(*) Fuel Pressure (Monitored on CNG) – Fuel pressure is controlled by the fuel pressure regulator. The PCM cannot detect a clogged fuel pump inlet filter, clogged in-line fuel filter, or a pinched fuel supply.(*) Fuel Injectors – The PCM cannot detect if the fuel injector is clogged, the pintle is sticking, or the wrong injectors are installed.(*) Fuel Requirements – Poor quality gasoline can cause problems such as hard starting, stalling, and stumble. Use of methanol-gasoline blends may result in starting and driveability problems. (See individual symptoms and their definitions in Section 12.0 (Glossary of Terms) at the back of this book.) PCM Grounds – The PCM cannot detect a poor system ground. However, a diagnostic trouble code may be stored in the PCM as a result of this condition. Throttle Body Air Flow – The PCM cannot detect a clogged or restricted air cleaner inlet or filter element.(*) Exhaust System – The PCM cannot detect a plugged, restricted, or leaking exhaust system.(*) Cylinder Compression – The PCM cannot detect uneven, low, or high engine cylinder compression.(*) Excessive Oil Consumption – Although the PCM monitors the exhaust stream oxygen content through the oxygen sensor when the system is in a closed loop, it cannot determine excessive oil consumption. (*)NOTE: Any of these conditions could result in a rich or lean condition causing an oxygen sensor trouble code to be stored in the PCM, or the vehicle may exhibit one or more of the driveability symptoms listed in TEST NTC-1A - No Trouble Code Test Menu.

10

3.3

Diagnostic Trouble Codes

Each diagnostic trouble code is diagnosed by following a specific testing procedure. The diagnostic test procedures contain step-by-step instructions for determining the cause of trouble codes as well as no trouble code problems. It is not necessary to perform all of the tests in this book to diagnose an individual code. Always begin by reading the diagnostic trouble codes using the DRB. This procedure begins in the DTC TEST – Checking the System for Diagnostic Trouble Codes. This will direct you to the specific test(s) that must be performed.

G E N E R A L I N F O R M A T I O N

3.3.1

Hard Code

A diagnostic trouble code that comes back within one cycle of the ignition key is a ‘‘hard’’ code. This means that the defect is there every time the powertrain control module checks that circuit or function. Procedures in this manual verify if the trouble code is a hard code at the beginning of each test. When it is not a hard code, an ‘‘intermittent’’ test must be performed.

3.3.2

Intermittent Code

A diagnostic trouble code that is not there every time the powertrain control module checks the circuit is an ‘‘intermittent’’ code. Most intermittent codes are caused by wiring or connector problems. Defects that come and go like this are the most difficult to diagnose; they must be looked for under specific conditions that cause them. The following checks may assist you in identifying a possible intermittent problem:
•

Visually inspect related wire harness connectors. Look for broken, bent, pushed out, or corroded terminals. Visually inspect the related harnesses. Look for chafed, pierced, or partially broken wire. Refer to any hotlines or technical service bulletins that may apply.

• •

3.3.3

Reset Counter

The reset counter counts the number of times the vehicle has been started since codes were last set, erased, or the battery was disconnected. The reset counter will count up to 255 start counts. The number of starts helps determine when the trouble code actually happened. This is recorded by the PCM and can be viewed on the DRB as the RESET COUNTER. When there are no trouble codes stored in memory, the DRB will display ‘‘NO TROUBLE CODES FOUND’’ and the reset counter will show ‘‘RESET COUNT = XXX.’’

3.3.4

Handling No Trouble Code Problems

After reading Section 3.0 (System Description and Functional Operation), you should have a better understanding of the theory and operation of the on-board diagnostics, and how this relates to the diagnosis of a vehicle that may have a driveability-related symptom or complaint. The ‘‘no code’’ system is broken down into three test methods: – – – No Code Complete Test No Code Quick Individual Test No Code Quick Symptom Test

3.4

Using the DRB

Refer to the DRB user’s guide for instructions and assistance with reading trouble codes, erasing trouble codes, and other DRB functions.
11

G E N E R A L I N F O R M A T I O N

3.5

DRB Error Messages and Blank Screen

Under normal operation, the DRB will display one of only two error messages: – User-Requested WARM Boot or User-Requested COLD Boot If the DRB should display any other error message, record the entire display and call the MDS Hotline, or call for information and assistance at 1-800-825-8737. This is a sample of such an error message display: ver: 2.14 date: 26 Jul93 file: key_itf.cc date: Jul 26 1993 line: 548 err: 0x1 User-Requested COLD Boot Press MORE to switch between this display and the application screen. Press F4 when done noting information.

3.5.1

DRB Does Not Power Up

If the LED’s do not light or no sound is emitted at start up, check for loose cable connections or a bad cable. Check the vehicle battery voltage (data link connector cavity 16). A minimum of 11 volts is required to adequately power the DRB. If all connections are proper between the DRB and the vehicle or other devices, and the vehicle battery is fully charged, an inoperative DRB may be the result of faulty cable or vehicle wiring. For a blank screen, refer to the appropriate body diagnostics manual.

3.5.2

Display Is Not Visible

Low temperatures will affect the visibility of the display. Adjust the contrast to compensate for this condition.

12

4.0 4.1

SYSTEM COMPONENT LOCATIONS Powertrain Control Module

AB BODY

G E N E R A L I N F O R M A T I O N

CAV A2 A4 A6 A7 A8 A10 A11 A15 A16 A17 A18 A19 A20 A22 A23 A24 A25 A27 A31 A32 B1 B2 B4 B5 B6 B8 B10 B11 B12 B13 B15

CIRCUIT F18 LG/BK K4 BK/LB T41 BR/OR K19 GY K24 GY/BK K60 YL/BK K40 BR/WT K21 BK/RD K2 TN/BK K6 VT/WT K44 TN/YL K39 GY/RD K59 VT/BK A14 RD/WT K22 OR/DB K41 BK/LG K341 TN/WT K1 DG/RD Z1 BK/TN Z1 BK/TN T34 GY/BK K26 VT K11 WT/DB K13 YL/WT K38 GY T59 PK K20 K54 K58 K28 K12 DG/WT OR/BK BR/DB GY/LB TN

FUNCTION Fused Ignition Switch Output Sensor Ground P/N Position Switch Sense Ignition Coil Driver #1 Crank Position Sensor Signal Idle Air Control #2 Driver Idle Air Control #3 Driver Intake Air Temp Sensor Signal ECT Sensor Signal 5-Volt Supply Camshaft Position Sensor Signal Idle Air Control #1 Driver Idle Air Control #4 Driver Fused B(+) Throttle Position Sensor Signal Upstream O2 Sensor Signal Downstream O2 Sensor Signal MAP Sensor Signal Ground Ground Trans Temp Sensor Signal Injector #7 Driver Injector #1 Driver Injector #3 Driver Injector #5 Driver Governor Pressure Solenoid Control Generator Field Driver TCC Solenoid Control Injector #6 Driver Injector #8 Driver Injector #2 Driver

CAV B16 B21 B22 B25 B27 B28 B29 B30 B31 C1 C3 C4 C5 C6 C11 C12 C13 C15 C16 C17 C19 C20 C22 C23 C24 C26 C27 C29 C32

CIRCUIT K14 LB/BR T60 OR/WT G79 TN/PK T13 DB/BK G7 WT/OR T14 LG/WT T25 LG/RD T30 VT/LB K7 OR C13 DB/OR K51 DB/YL V36 TN/RD V35 LG/RD T18 LG/OR V32 YL/RD A142 DG/OR T6 OR/WT K118 PK/YL G12 TN/BK G3 BK/PK K31 BR K52 PK/BK C20 BR/WT C90 LG K29 WT/PK G8 LB/BK D21 PK D20 LG/WT V33 WT/LG

FUNCTION Injector #4 Driver Solenoid Control 3-4 Shift Fuel Temp Sensor Signal Output Shaft Speed Sensor Ground Vehicle Speed Sensor Signal Output Shaft Speed Sensor Signal Governor Pressure Signal Transmission Relay Control 5-Volt Supply A/C Comp Clutch Relay Control Auto Shutdown Relay Control S/C Vacuum Solenoid Control S/C Vent Solenoid Control Overdrive Off Lamp Driver 12 Volt Supply Auto Shutdown Relay Output Overdrive Off Switch Sense Battery Temp Sensor Signal Generator Lamp Driver MIL (Check Engine) Lamp Driver Fuel Pump Relay Control Evaporative Emission Solenoid Ctrl A/C Request Signal A/C Select Signal Brake Switch Sense Low Fuel Sense SCI Transmit SCI Receive Speed Control Switch Signal

13

G E N E R A L I N F O R M A T I O N

4.1

Powertrain Control Module (Continued)

AN BODY

CAV A2 A4 A6 A7 A8 A10 A11 A15 A16 A17 A18 A19 A20 A22 A23 A24 A25 A27 A28 A31 A32 B1 B2 B4 B5 B6 B8 B10 B11 B12 B13 B15 B16 B21

CIRCUIT A21 DB K4 BK/LB T41 BR/YL K19 GY K24 GY/BK K60 YL/BK K40 BR/WT K21 BK/RD K2 TN/BK K6 VT/WT K44 TN/YL K39 GY/RD K59 VT/BK A14 RD/WT K22 OR/DB K141 TN/WT K341 TN/PK K1 DG/RD K242 DG/LB Z12 BK/TN Z12 BK/TN T54 VT K26 DB K11 WT/DB K13 YL/WT K38 GY T59 PK K20 DG K54 OR/BK K58 BR/DB K28 GY/LB K12 TN K14 LB/BR T60 BR

FUNCTION Fused Ignition Switch Output Sensor Ground P/N Position Switch Sense Ignition Coil Driver #1 Crank Position Sensor Signal Idle Air Control #2 Driver Idle Air Control #3 Driver Intake Air Temp Sensor Signal ECT Sensor Signal 5-Volt Supply Camshaft Position Sensor Signal Idle Air Control #1 Driver Idle Air Control #4 Driver Fused B(+) Throttle Position Sensor Signal Upstream O2 Sensor Signal Downstream O2 Sensor Signal MAP Sensor Signal Fuel Pressure Sensor Signal Ground Ground Trans Temp Sensor Signal Injector #7 Driver Injector #1 Driver Injector #3 Driver Injector #5 Driver Governor Pressure Solenoid Control Generator Field Driver TCC Solenoid Control Injector #6 Driver Injector #8 Driver Injector #2 Driver Injector #4 Driver Solenoid Control 3-4 Shift

CAV B22 B25 B27 B28 B29 B30 B31 C1 C2 C3 C4 C5 C6 C7 C11 C12 C13 C15 C16 C17 C19 C20 C22 C23 C24 C26 C27 C28 C29 C30 C31 C32

CIRCUIT K221 TN/PK T13 DB/BK G7 WT/OR T14 LG/WT T25 LG/RD T30 VT/LB T33 RD/YL C13 DB/OR C27 DB/PK K51 DB/YL V36 TN/RD V35 LG/RD T18 LG/OR G14 PK/BK V32 YL/RD A142 DG/OR T6 OR/WT K118 PK/YL G12 DG/YL G3 BK/PK K31 BR K52 PK/BK C20 BR C90 LG K29 WT/PK G8 LB/BK D21 PK D2 WT/PK D20 LG D1 VT/BR G21 GY/LB V33 WT/LG

FUNCTION Fuel Temperature Sensor Signal Output Shaft Speed Sensor Ground Vehicle Speed Sensor Signal Output Shaft Speed Sensor Signal Governor Pressure Signal Transmission Relay Control 5-Volt Supply A/C Comp Clutch Relay Control Radiator Fan Relay Control Auto Shutdown Relay Control S/C Vacuum Solenoid Control S/C Vent Solenoid Control Overdrive Off Lamp Driver Trans Temp Lamp Driver 12 Volt Supply Auto Shutdown Relay Output Overdrive Off Switch Sense Battery Temp Sensor Signal Generator Lamp Driver MIL (Check Engine) Lamp Driver Fuel Pump Relay Control Evaporative Emission Solenoid Ctrl A/C Request Signal A/C Select Signal Brake Switch Sense Low Fuel Sense SCI Transmit CCD Bus (-) SCI Receive CCD Bus (+) Tachometer Signal Speed Control Switch Signal

14

BR BODY (Gasoline Engines) The PCM is located in the rear engine compartment, passenger side.

G E N E R A L I N F O R M A T I O N

CAV A1 A2 A3 A4 A5 A6 A7 A8 A9 A10 A11 A15 A16 A17 A18 A19 A20 A22 A23 A24 A24 A25 A26 A26 A27 A28 A29 A31 A32 B1 B2 B3 B4 B5 B6 B8 B10 B11

CIRCUIT K32 YL/GY F18 LG/BK K18 RD/BK K4 BK/LB K43 DG/GY T41 BK/WT K19 BK/GY K24 GY/BK K17 DB/WT K60 YL/BK K40 BR/WT K21 BK/RD K2 TN/BK K6 VT/WT K44 TN/YL K39 GY/RD K59 VT/BK A14 RD/WT K22 OR/DB K141 TN/WT K41 BK/DG K341 OR/BK K41 BK/DG K241 BK/DG K1 DG/RD K242 DG/LB K441 TN/RD Z12 BK/TN Z12 BK/TN K54 VT K26 VT/TN K115 TN K11 WT/DB K13 YL/WT K38 GY K88 VT/WT K20 DG K54 OR/BK

FUNCTION Ignition Coil Driver #4 Fused Ignition Switch Output Ignition Coil Driver #3 Sensor Ground Ignition Coil Driver #5 P/N Position Switch Sense Ignition Coil Driver #1 Crank Position Sensor Signal Ignition Coil Driver #2 Idle Air Control #2 Driver Idle Air Control #3 Driver Intake Air Temp Sensor Signal ECT Sensor Signal 5-Volt Supply Camshaft Position Sensor Signal Idle Air Control #1 Driver Idle Air Control #4 Driver Fused B(+) Throttle Position Sensor Signal Upstream O2 Sensor Signal Upstream O2 Sensor Signal Downstream O2 Sensor Signal Right Upstream O2 Sensor Signal Right Upstream O2 Sensor Signal MAP Sensor Signal Fuel Pressure Sensor Signal Center O2 Sensor Signal Ground Ground Trans Temp Sensor Signal Injector #7 Driver Injector #9 Driver Injector #1 Driver Injector #3 Driver Injector #5 Driver Governor Pressure Solenoid Control Generator Field Driver TCC Solenoid Control

CAV B12 B13 B14 B15 B16 B21 B22 B25 B27 B28 B29 B30 B31 B32 C1 C3 C4 C5 C6 C7 C11 C12 C13 C15 C16 C17 C18 C19 C20 C22 C23 C24 C26 C27 C29 C31 C32

CIRCUIT K58 BR/DB K28 GY/LB K116 WT/DB K12 TN K14 LB/BR T60 BR K221 TN/PK T13 DB/BK G7 WT/OR T14 LG/BK T25 LG/WT K30 PK K7 OR K35 GY/YL C13 DB/OR K51 DB/YL V36 TN/RD V35 LG/RD T18 LG/OR G14 PK/BK V32 YL/RD A142 DG/OR T6 OR/WT K118 PK/YL G12 TN/YL G3 BK/PK G24 GY/PK K31 BR/WT K52 PK C20 BR C90 LG V40 WT/PK K226 DB/WT D21 PK/DB D20 DG G21 GY/LB V37 RD/LG

FUNCTION Injector #6 Driver Injector #8 Driver Injector #10 Driver Injector #2 Driver Injector #4 Driver Solenoid Control 3-4 Shift Fuel Temp Sensor Signal Output Shaft Speed Sensor Ground Vehicle Speed Sensor Signal Output Shaft Speed Sensor Signal Governor Pressure Signal Transmission Relay Control 5-Volt Supply EGR Solenoid Control A/C Comp Clutch Relay Control Auto Shutdown Relay Control S/C Vacuum Solenoid Control S/C Vent Solenoid Control Overdrive Off Lamp Driver Trans Temp Lamp Driver 12 Volt Supply Auto Shutdown Relay Output Overdrive Off Switch Sense Battery Temp Sensor Signal Generator Lamp Driver MIL (Check Engine) Lamp Driver Service Reminder Indicator Driver Fuel Pump Relay Control Evaporative Emission Solenoid Ctrl A/C Request Signal A/C Select Signal Brake Switch Sense Low Fuel Sense SCI Transmit SCI Receive Tachometer Signal Speed Control Switch Signal

15

G E N E R A L I N F O R M A T I O N

4.1

Powertrain Control Module (Continued)

BR BODY 5.9L DIESEL

CAV A2 A4 A6 A7 A8 A9 A12 A15 A17 A22 A23 A27 A31 A32 B1 B8 B10 B11 B20 B21 B25 B27 B28

CIRCUIT F18 LG/BK K4 BK/LB T41 BK/WT S21 YL/BK K24 GY/BK S22 OR/BK D28 LG/RD K21 BK/RD K6 VT/WT A14 RD/WT K22 OR/DB K1 DG/RD Z12 BK/TN Z12 BK/TN K54 VT K88 VT/WT K20 DG K54 OR/BK G85 OR/BK T60 BR T13 DB/BK G7 WT/OR T14 LG/BK

FUNCTION Fused Ignition Switch Output Sensor Ground P/N Position Switch Sense Air Intake Heater Relay #1 Control Crank Position Sensor Signal Air Intake Heater Relay #2 Control EGR Fault Monitor Intake Air Temp Sensor Signal 5-Volt Supply Fused B(+) Throttle Position Sensor Signal Water-In-Fuel Sensor Signal Ground Ground Trans Temp Sensor Signal Governor Pressure Solenoid Control Generator Field Driver TCC Solenoid Control Wait to Start Lamp Driver Solenoid Control 3-4 Shift Output Shaft Speed Sensor Ground Vehicle Speed Sensor Signal Output Shaft Speed Sensor Signal

CAV B29 B30 B31 C1 C3 C4 C5 C6 C7 C9 C11 C12 C13 C15 C16 C17 C18 C22 C23 C24 C27 C29 C31 C32

CIRCUIT T25 LG/WT K30 PK K7 OR C13 DB/OR K51 DB/YL V36 TN/RD V35 LG/RD T18 LG/OR G14 PK/BK D29 PK/DG V32 YL/RD A142 DG/OR T6 OR/WT K118 PK/YL G12 TN/YL G3 BK/PK G86 TN/OR C20 BR C90 LG V40 WT/PK D21 PK/DB D20 DG G21 GY/LB V37 RD/LG

FUNCTION Governor Pressure Signal Transmission Relay Control 5-Volt Supply A/C Comp Clutch Relay Control Auto Shutdown Relay Control S/C Vacuum Solenoid Control S/C Vent Solenoid Control Overdrive Off Lamp Driver Trans Temp Lamp Driver EGR Test Mode 12 Volt Supply Auto Shutdown Relay Output Overdrive Off Switch Sense Battery Temp Sensor Signal Generator Lamp Driver MIL (Check Engine) Lamp Driver Water-in-Fuel Lamp Driver A/C Request Signal A/C Select Signal Brake Switch Sense SCI Transmit SCI Receive Tachometer Signal Speed Control Switch Signal

16

XJ BODY

G E N E R A L I N F O R M A T I O N

CAV A2 A4 A6 A7 A8 A10 A11 A12 A15 A16 A17 A18 A19 A20 A22 A23 A24 A25 A27 A31 A32 B4 B5 B6 B10 B11 B12

CIRCUIT A21 DB K4 BK/LB T41 BR/YL K19 GY K24 GY/BK K60 YL/BK K40 BR/WT K10 DB/OR K21 BK/RD K2 TN/BK K6 VT/WT K44 TN/YL K39 GY/RD K59 VT/BK A14 RD K22 OR/DB K41 BK/LG K341 TN/WT K1 DG/RD Z12 BK/TN Z12 BK/TN K11 WT/DB K13 YL/WT K38 GY K20 DG K54 OR/BK K58 BR/DB

FUNCTION Fused Ignition Switch Output Sensor Ground P/N Position Switch Sense Ignition Coil Driver #1 Crank Position Sensor Signal Idle Air Control #2 Driver Idle Air Control #3 Driver Power Steering Pressure Switch Sense Intake Air Temp Sensor Signal ECT Sensor Signal 5-Volt Supply Camshaft Position Sensor Signal Idle Air Control #1 Driver Idle Air Control #4 Driver Fused B(+) Throttle Position Sensor Signal Upstream O2 Sensor Signal Downstream O2 Sensor Signal MAP Sensor Signal Ground Ground Injector #1 Driver Injector #3 Driver Injector #5 Driver Generator Field Driver TCC Solenoid Control Injector #6 Driver

CAV B15 B16 B27 B31 C1 C2 C3 C4 C5 C11 C12 C15 C16 C17 C19 C20 C22 C23 C24 C26 C27 C28 C29 C30 C31 C32

CIRCUIT K12 TN K14 LB/BR G7 WT/OR K7 OR C13 DB/OR C27 DB/PK K51 DB/YL V36 TN/RD V35 LG/RD V32 YL/RD A142 DG/OR K118 PK/YL G14 PK/BK G3 BK/PK K31 BR K52 PK/BK C21 DB/OR C90 LG K29 WT/PK G4 DB D21 PK D2 WT/BK D20 LG D1 VT/BR G21 GY/LB V33 WT/LG

FUNCTION Injector #2 Driver Injector #4 Driver Vehicle Speed Sensor Signal 5-Volt Supply A/C Comp Clutch Relay Control Radiator Fan Relay Control Auto Shutdown Relay Control S/C Vacuum Solenoid Control S/C Vent Solenoid Control 12 Volt Supply Auto Shutdown Relay Output Battery Temp Sensor Signal Generator Lamp Driver MIL (Check Engine) Lamp Driver Fuel Pump Relay Control Evaporative Emission Solenoid Ctrl A/C Request Signal A/C Select Signal Brake Switch Sense Low Fuel Sense SCI Transmit CCD Bus (-) SCI Receive CCD Bus (+) Tachometer Signal Speed Control Switch Signal

17

G E N E R A L I N F O R M A T I O N

4.1

Powertrain Control Module (Continued)

ZJ BODY

CAV A2 A4 A6 A7 A8 A10 A11 A15 A16 A17 A18 A19 A20 A22 A23 A24 A25 A27 A31 A32 B1 B2 B4 B5 B6 B8 B10 B11 B12 B13 B15 B16 B21

CIRCUIT F99 RD/OR K4 BK/LB T41 BK/WT K19 GY/WT K27 RD/LG K59 VT/BK K40 BR/WT K21 BK/RD K2 TN/BK K25 WT/BK K24 GY/BK K60 YL/BK K39 GY/RD F5 RD/YL K22 OR/DB K41 BK/OR K141 BK/PK K70 RD/WT Z12 BK/TN Z12 BK/TN T54 VT K17 DB/WT K11 WT/DB K13 YL/WT K38 GY T59 PK K20 DG T22 DG/LB K58 BR/YL K18 DB/YL K12 TN K14 LB/BR T60 BR

FUNCTION Fused Ignition Switch Output Sensor Ground P/N Position Switch Sense Ignition Coil Driver #1 Crank Position Sensor Signal Idle Air Control #2 Driver Idle Air Control #3 Driver Intake Air Temp Sensor Signal ECT Sensor Signal 5-Volt Supply Camshaft Position Sensor Signal Idle Air Control #1 Driver Idle Air Control #4 Driver Fused B(+) Throttle Position Sensor Signal Upstream O2 Sensor Signal Downstream O2 Sensor Signal MAP Sensor Signal Ground Ground Trans Temp Sensor Signal Injector #7 Driver Injector #1 Driver Injector #3 Driver Injector #5 Driver Governor Pressure Solenoid Control Generator Field Driver TCC Solenoid Control Injector #6 Driver Injector #8 Driver Injector #2 Driver Injector #4 Driver Solenoid Control 3-4 Shift

CAV B23 B25 B27 B28 B29 B30 B31 B32 C1 C3 C4 C5 C6 C10 C11 C12 C13 C14 C15 C19 C20 C22 C24 C26 C27 C28 C29 C30 C32

CIRCUIT G6 GY/WT T13 DB/BK G7 WT/OR T14 LG/WT T25 LG T66 BR/OR K6 VT/WT K35 GY/YL C13 DB/RD K900 PK/BK V36 TN/RD V35 LG/RD G68 BR/YL J95 DG/RD V32 YL/RD A142 DG/OR T9 OR J96 VT/RD T222 YL/RD K81 PK K52 PK/BK C3 DB/BK L53 BR G40 LB/BK D83 BK/PK D2 WT/BK D84 BK/WT D1 VT/BR K95 PK

FUNCTION Oil Pressure Switch Signal Output Shaft Speed Sensor Ground Vehicle Speed Sensor Signal Output Shaft Speed Sensor Signal Governor Pressure Signal Transmission Relay Control 5-Volt Supply EGR Solenoid Control A/C Comp Clutch Relay Control Auto Shutdown Relay Control S/C Vacuum Solenoid Control S/C Vent Solenoid Control Overdrive Off Lamp Driver Leak Detection Pump Solenoid Ctrl 12 Volt Supply Auto Shutdown Relay Output Overdrive Off Switch Sense Leak Detection Pump Switch Sense Battery Temp Sensor Signal Fuel Pump Relay Control Evaporative Emission Solenoid Ctrl A/C Request Signal Brake Switch Sense Low Fuel Sense SCI Transmit CCD Bus (-) SCI Receive CCD Bus (+) Speed Control Switch Signal

18

4.2

Controls & Solenoids
BR DIESEL

BR 5.9L HD GASOLINE

G E N E R A L I N F O R M A T I O N

BR BODY

AB, AN, BR EXCEPT 8.0L

AN 2.5L

BR 8.0L

19

G E N E R A L I N F O R M A T I O N

4.2
ZJ 4.0L

Controls & Solenoids (Continued)
ZJ 5.2L

XJ BODY

AB BODY

AN XJ BODIES

BR BODY

20

ZJ BODY

AB BODY

G E N E R A L I N F O R M A T I O N

AN 2.5L

AN EXCEPT 2.5L BR EXCEPT 8.0L

BR 8.0L

XJ BODY

21

G E N E R A L I N F O R M A T I O N

4.2

Controls & Solenoids (Continued)
ZJ 4.0L

BR DIESEL

ZJ 5.2L

AB BODY

AN BODY

22

BR BODY

ZJ BODY

G E N E R A L I N F O R M A T I O N

2.5L AND 4.0L

3.9L, 5.2L, 5.9L EXCEPT 8.0L

BR 8.0L

AB BODY

23

G E N E R A L I N F O R M A T I O N

4.2

Controls & Solenoids (Continued)
XJ BODY

AN BR BODIES

ZJ BODY

3.9L, 5.2L AND 5.9L

2.5L AND 4.0L

BR 8.0L

24

AB, AN AND XJ BODIES

BR EXCEPT 8.0L

G E N E R A L I N F O R M A T I O N

ZJ

BR 8.0L

3.9L, 5.2L AND 5.9L EXCEPT CNG AND DIESEL

AN XJ 2.5L

25

G E N E R A L I N F O R M A T I O N

4.2
BR 8.0L

Controls & Solenoids (Continued)
XJ, ZJ 4.0L

AB, AN, BR 5.2L CNG

AB, AN, BR BODIES

XJ BODY

ZJ BODY

26

ZJ 4.0L

ZJ 4.0L

G E N E R A L I N F O R M A T I O N

AB, AN, BR AND ZJ BODIES

AB BODY

AN BODY

BR BODY

27

G E N E R A L I N F O R M A T I O N

4.2

Controls & Solenoids (Continued)
AB BODY

ZJ BODY

BR BODY

XJ BODY

ZJ BODY

ALL BODIES

28

AB 3.9L

AB BODY

G E N E R A L I N F O R M A T I O N

4.3

Data Link Connectors
AB BODY

AB BODY

AN BODY

AN BODY

29

G E N E R A L I N F O R M A T I O N

4.3

Data Link Connectors (Continued)
BR BODY

BR BODY

XJ BODY

XJ BODY

4.4

Sensors
ZJ BODY

ZJ BODY

30

AB BODY

AN BODY

G E N E R A L I N F O R M A T I O N

BR BODY

XJ BODY

ZJ BODY

AB, AN , BR , XJ BODIES

31

G E N E R A L I N F O R M A T I O N

4.4

Sensors (Continued)
AB, AN, BR EXCEPT 2.5L, 8.0L AND DIESEL

ZJ BODY

2.5L AND 4.0L

BR 8.0L

ZJ 5.2L

BR 5.9L DIESEL

32

AB, AN, BR BODIES

XJ BODY

G E N E R A L I N F O R M A T I O N

ZJ BODY

3.9L, 5.2L, 5.9L

2.5L AND 4.0L

BR 8.0L

33

G E N E R A L I N F O R M A T I O N

4.4

Sensors (Continued)
ZJ BODY

AB, AN, BR AND XJ BODIES

3.9L, 5.2L 5.9L

2.5L AND 4.0L

BR 8.0L

AB, AN, BR AND ZJ 5.2L

34

XJ BODY

ZJ 4.0L

G E N E R A L I N F O R M A T I O N

5.2L CNG

5.2L CNG

ALL 4XRE TRANS.

AB BODY

35

G E N E R A L I N F O R M A T I O N

4.4

Sensors (Continued)
BR BODY

AN BODY

ZJ BODY

3.9L, 5,2L, 5.9L

2.5L AND 4.0L

BR 5.9L DIESEL

36

BR 8.0L

AB, AN, BR AND XJ BODIES

G E N E R A L I N F O R M A T I O N

ZJ BODY

3.9L, 5.2L, 5.9L

2.5L AND 4.0L

BR 8.0L

37

G E N E R A L I N F O R M A T I O N

4.4

Sensors (Continued)
BR 8.0L

AB, AN, XJ AND BR EXCEPT 8.0L

ZJ BODY

38

AB 3.9L, 5.2L AND ZJ 5.2L 1/1

AB 5.9L 1/1

G E N E R A L I N F O R M A T I O N

AN EXCEPT 2.5L, BR EXCEPT 5.9L HD AND 8.0L 1/1

BR 5.9L AND 8.0L HD 1/1 2/1

XJ BODY AND ZJ 4.0L 1/1

BR 8.0L CAL 1/1 1/2 1/3 2/1

39

G E N E R A L I N F O R M A T I O N

4.4

Sensors (Continued)
AN BODY 1/1

AB BODY 1/1

BR 3.9L, 5.2L, 5.9L EXCEPT HD 1/1

BR 5.9L HD AND 8.0L 1/1

XJ 2.5L AND 4.0L 1/1

ZJ 5.2L AND 4.0L 1/1

40

AB BODY 1/2

AN, BR EXCEPT 5.9L HD AND 8.0L AND XJ 1/2

G E N E R A L I N F O R M A T I O N

ZJ BODY 1/2

BR 8.0L CAL 1/1 1/2 1/3 2/1

AB BODY 1/2

AN BODY1/2

41

G E N E R A L I N F O R M A T I O N

4.4

Sensors (Continued)
BR 8.0L 1/2

BR 3.9L, 5.2L, 5.9L 1/2

XJ 2.5L AND 4.0L 1/2

ZJ BODY 1/2

BR 8.0L 1/3

BR 5.9L AND 8.0L HD 2/1

42

ZJ 4.0L

ZJ 5.2L

G E N E R A L I N F O R M A T I O N

ZJ BODY

ALL 4XRE TRANS

ALL BODIES EXCEPT BR

BR BODY

43

G E N E R A L I N F O R M A T I O N

4.4

Sensors (Continued)
AN 2.5L XJ AND ZJ 4.0L

AB, AN EXCEPT 2.5L, BR 3.9L, 5.2L, 5.9L

ZJ 5.2L

BR 5.9L DIESEL

BR 8.0L

AB, AN AND BR EXCEPT DIESEL

44

BR 5.9L DIESEL

XJ BODY

G E N E R A L I N F O R M A T I O N

ZJ BODY

AB, EX 3.9L, AN, EX 2.5L, BR

AB, EX 3.9L, AN, EX 2.5L, BR

AB BODY

45

G E N E R A L I N F O R M A T I O N

4.4

Sensors (Continued)
BR BODY

AN BODY

ZJ BODY

3 SPEED AUTO TRANS

MANUAL TRANS AND 4X4

4 SPEED AUTO TRANS

46

AB, BR AND XJ BODIES

AN BODY

G E N E R A L I N F O R M A T I O N

ZJ BODY

BR 5.9L DIESEL

BR 5.9L DIESEL

47

G E N E R A L I N F O R M A T I O N

4.5

Fuel System
AB BODY

AB BODY

AN BODY

AN BODY

BR BODY

BR BODY

48

XJ BODY

XJ BODY

G E N E R A L I N F O R M A T I O N

ZJ BODY

ZJ BODY

BR 5.9L DIESEL

BR 5.9L DIESEL

49

G E N E R A L I N F O R M A T I O N

4.5

Fuel System (Continued)
BR 5.9L DIESEL

BR 5.9L DIESEL

BR 5.9L DIESEL

CNG FUEL TEMP & REG

AB 5.2L CNG

AN, BR BODIES

50

AB 5.2L CNG

AN, BR 5.2L CNG

G E N E R A L I N F O R M A T I O N

AB 5.2L CNG

AN, BR 5.2L CNG

4.6

Relays
AN BODY

AB BODY

51

G E N E R A L I N F O R M A T I O N

4.6

Relays (Continued)
XJ BODY

BR BODY

ZJ BODY

AB BODY

AN BODY

BR BODY

52

XJ BODY

ZJ BODY

G E N E R A L I N F O R M A T I O N

BR 5.9L DIESEL

BR 5.9L DIESEL

AB BODY

AN BODY

53

G E N E R A L I N F O R M A T I O N

4.6

Relays (Continued)
XJ BODY

BR BODY

ZJ BODY

AB EXCEPT CNG

AN EXCEPT CNG

BR EXCEPT CNG

54

XJ BODY

ZJ BODY

G E N E R A L I N F O R M A T I O N

AB CNG

AN CNG

BR CNG

BR 5.9L DIESEL

55

G E N E R A L I N F O R M A T I O N

4.6

Relays (Continued)
BR 5.9L DIESEL

BR 5.9L DIESEL

AN 2.5L

XJ 4.0L

AB BODY

AN BODY

56

BR BODY

XJ BODY

G E N E R A L I N F O R M A T I O N

ZJ BODY

AB EXCEPT 3.9L

AB EXCEPT 3.9L

AN EXCEPT DIESEL

57

G E N E R A L I N F O R M A T I O N

4.6

Relays (Continued)
ZJ BODY

BR BODY

4.7

Switches
XJ AND ZJ BODIES

AB, AN AND BR BODIES

AB BODY

AN AND XJ BODIES

58

BR BODY

ZJ BODY

G E N E R A L I N F O R M A T I O N

AB BODY

AN BODY

BR BODY

ZJ BODY

59

G E N E R A L I N F O R M A T I O N

4.7

Switches (Continued)
BR BODY

AB, AN BODIES

ZJ BODY

AB, AN, BR AND ZJ BODIES

XJ BODY

AB BODY

60

AN BODY

BR BODY

G E N E R A L I N F O R M A T I O N

XJ BODY

ZJ BODY

AB, AN AND BR BODIES

ZJ BODY

61

G E N E R A L I N F O R M A T I O N

4.7

Switches (Continued)
ALL EXCEPT ZJ

XJ BODY

ZJ BODY

4.8

Lamps & Indicators
AN BODY

AB BODY

62

BR BODY

XJ BODY

G E N E R A L I N F O R M A T I O N

AB BODY

AN BODY

BR BODY

XJ BODY

63

G E N E R A L I N F O R M A T I O N

4.8

Lamps & Indicators (Continued)
AN BODY

AB BODY

BR BODY

ZJ BODY

AB, AN BODIES

BR BODY

64

ZJ BODY

AN BODY

G E N E R A L I N F O R M A T I O N

BR BODY

XJ BODY

BR 5.9L & 8.0L

AN BODY

65

G E N E R A L I N F O R M A T I O N

4.8

Lamps & Indicators (Continued)
XJ BODY

BR BODY

BR 5.9L DIESEL

BR 5.9L DIESEL

5.0 5.1

DISCLAIMERS, SAFETY, WARNINGS Disclaimers

All information, illustrations, and specifications contained in this manual are based on the latest information available at the time of publication. The right is reserved to make changes at any time without notice.

5.2 5.2.1

Safety Technician Safety Information

WARNING: Engines produce carbon monoxide that is odorless, causes slower reaction time, and can lead to serious injury. When the engine is operating, keep service areas WELL VENTILATED or attach the vehicle exhaust system to the shop exhaust removal system.

66

Set the parking brake and block the wheels before testing or repairing the vehicle. It is especially important to block the wheels on front-wheel drive vehicles; the parking brake does not hold the drive wheels. When servicing a vehicle, always wear eye protection, and remove any metal jewelry such as watchbands or bracelets that might make an inadvertent electrical contact. When diagnosing a body system problem, it is important to follow approved procedures where applicable. These procedures can be found in General Information Section 9.0 (Specifications) or in service manual procedures. Following these procedures is very important to the safety of individuals performing diagnostic tests.

G E N E R A L I N F O R M A T I O N

5.2.2

Vehicle Preparation for Testing

Make sure the vehicle being tested has a fully charged battery. If it does not, false diagnostic codes or error messages may occur.

5.2.3

Servicing Sub-Assemblies

Some components of the powertrain system are intended to be serviced in assembly only. Attempting to remove or repair certain system sub-components may result in personal injury and/or improper system operation. Only those components with approved repair and installation procedures in the service manual should be serviced.

5.2.4

DRBIII Safety Information

WARNING: Exceeding the limits of the DRB multimeter is dangerous. It can expose you to serious or possibly fatal injury. Carefully read and understand the cautions and the specification limits.
• • • • •

Follow the vehicle manufacturer’s service specifications at all times. Do not use the DRB if it has been damaged. Do not use the test leads if the insulation is damaged or if metal is exposed. To avoid electrical shock, do not touch the test leads, tips, or the circuit being tested. Choose the proper range and function for the measurement. Do not try voltage or current measurements that may exceed the rated capacity. Do not exceed the limits shown in the table below: FUNCTION Volts Ohms (resistance)* Frequency Measured Frequency Generated Temperature INPUT LIMIT 0 - 500 peak volts AC 0 - 500 volts DC 0 - 1.12 megohms 0 - 10 kHz -58 - 1100°F -50 - 600°C

•

* Ohms cannot be measured if voltage is present. Ohms can be measured only in a non-powered circuit.
•

Voltage between any terminal and ground must not exceed 500v DC or 500v peak AC.

67

G E N E R A L I N F O R M A T I O N

• • •

Use caution when measuring voltage above 25v DC or 25v AC. The circuit being tested must be protected by a 10A fuse or circuit breaker. Use the low current shunt to measure circuits up to 10A. Use the high current clamp to measure circuits exceeding 10A. When testing for the presence of voltage or current, make sure the meter is functioning correctly. Take a reading of a known voltage or current before accepting a zero reading. When measuring current, connect the meter in series with the load. Disconnect the live test lead before disconnecting the common test lead. When using the meter function, keep the DRB away from spark plug or coil wires to avoid measuring error from outside interference.

•

• • •

5.3 5.3.1

Warnings Vehicle Damage Warnings

Before disconnecting any control module, make sure the ignition is ‘‘off.’’ Failure to do so could damage the module. When testing voltage or continuity at the powertrain control module, use the terminal side (not the wire end) of the connector. Do not probe a wire through the insulation; this will damage it and eventually cause it to fail because of corrosion. Be careful when performing electrical tests so as to prevent accidental shorting of terminals. Such mistakes can damage fuses or components. Also, a second code could be set, making diagnosis of the original problem more difficult.

5.3.2

Road Testing a Complaint Vehicle

Some complaints will require a test drive as part of the repair verification procedure. The purpose of the test drive is to try to duplicate the diagnostic code or symptom condition. CAUTION: Before road testing a vehicle, be sure that all components are reassembled. During the test drive, do not try to read the DRB screen while in motion. Do not hang the DRB from the rear view mirror or operate it yourself. Have an assistant available to operate the DRB.

68

7.0

DIAGNOSTIC INFORMATION AND PROCEDURES

7.1 GENERAL TROUBLESHOOTING

69

T R O U B L E C O D E T E S T S

DTC TEST

CHECKING THE SYSTEM FOR DIAGNOSTIC TROUBLE CODES (DTCs)

NOTE: The battery must be fully charged for any test in this manual. 1. Attempt to start the engine. Crank for up to 10 seconds if necessary. 2. Connect the DRB to the engine diagnostic connector. Write down the trouble codes that are displayed. 3. If the DRB screen displays ‘‘No Response’’, go the TEST NS-SEL. 4. If the DRB screen is blank or has a DRB message, go to General Information Section 3.5 in this manual. 5. If trouble code messages are displayed, refer to the trouble code list below and on the next page for the appropriate test. 6. If there are no trouble codes displayed, refer to one of the following: For Driveability problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-1A For No Start problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NS-SEL For Speed Control problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .SC-1A For Charging problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .CH-1A NOTE: The decimal test numbers for these trouble codes were derived from the hexadecimal codes as set in the PCM. Therefore, some test numbers will be missing because all codes are not applicable to the vehicles covered in this manual.
TROUBLE CODE DESCRIPTION [SDD] 3-4 SHIFT SOL, NO RPM DROP @ 3-4 SHIFT A/C CLUTCH RELAY CIRCUIT AUTO SHUTDOWN RELAY CONTROL CIRCUIT BATTERY TEMP SENSOR VOLTAGE TOO HIGH BATTERY TEMP SENSOR VOLTAGE TOO LOW CATALYTIC CONVERTER EFFICIENCY FAILURE CHARGING SYSTEM VOLTAGE TOO HIGH CHARGING SYSTEM VOLTAGE TOO LOW CLOSED LOOP TEMP NOT REACHED CNG PRESSURE SENSOR VOLTAGE TOO HIGH CNG PRESSURE SENSOR VOLTAGE TOO LOW CNG TEMP SENSOR VOLTAGE TOO HIGH CNG TEMP SENSOR VOLTAGE TOO LOW CYLINDER #1 MIS-FIRE CYLINDER #2 MIS-FIRE CYLINDER #3 MIS-FIRE CYLINDER #4 MIS-FIRE CYLINDER #5 MIS-FIRE CYLINDER #6 MIS-FIRE CYLINDER #7 MIS-FIRE CYLINDER #8 MIS-FIRE TC-165 TC-16 TC-10 TC-153 TC-153 TC-112 TC-6 TC-5 TC-128 TC-98 TC-99 TC-95 TC-94 TC-107 TC-107 TC-107 TC-107 TC-107 TC-107 TC-107 TC-107 Test # MIL Code 45 33 42 44 44 72,64 46 47 17 64 64 64 64 43 43 43 43 43 43 43 43 DTC HEX A5 10 0A 9A 99 70 06 05 80 62 63 5F 5E 6B 6C 6D 6E AE AF B0 B1 P 0783 N/A N/A P 1492 P 1493 P 0420 N/A N/A P 0125 P 1292 P 1293 P 0183 P 0182 P 0301 P 0302 P 0303 P 0304 P 0305 P 0306 P 0307 P 0308 Scan Tool

70

DTC TEST

CHECKING THE SYSTEM FOR DIAGNOSTIC TROUBLE CODES (DTCs)

TROUBLE CODE DESCRIPTION [SDD] (Pre-Cat) DOWNSTREAM O2 SENSOR HEATER FAILURE (Pre-Cat) DOWNSTREAM O2S VOLTS SHORTED TO GND (Pre-Cat) DOWNSTREAM O2S SHORTED TO VOLTAGE ECT SENSOR VOLTAGE TOO HIGH ECT SENSOR VOLTAGE TOO LOW EGR SOLENOID CIRCUIT EGR SYSTEM FAILURE ENGINE IS COLD TOO LONG EVAP LEAK MONITOR LARGE LEAK DETECTED EVAP LEAK MONITOR PINCHED HOSE FOUND EVAP LEAK MONITOR SMALL LEAK DETECTED EVAP PURGE FLOW MONITOR FAILURE EVAP PURGE SOLENOID CIRCUIT FUEL LEVEL SENDING UNIT VOLTS TOO HIGH FUEL LEVEL SENDING UNIT VOLTS TOO LOW FUEL LEVEL UNIT NO CHANGE OVER MILES FUEL PUMP RELAY CONTROL CIRCUIT FUEL SYSTEM LEAN FUEL SYSTEM RICH GENERATOR FIELD NOT SWITCHING PROPERLY GOV PRES ABOVE 3 PSI IN GEAR WITH 0 MPH GOV PRESS NOT EQUAL TO TARGET @ 15-20 PSI GOV PRESS SEN OFFSET VOLTS TOO LOW OR HIGH GOVERNOR PRESSURE SENSOR VOLTS TOO HI GOVERNOR PRESSURE SENSOR VOLTS TOO LOW GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS IDLE AIR CONTROL MOTOR CIRCUIT IGNITION COIL #1 PRIMARY CIRCUIT IGNITION COIL #2 PRIMARY CIRCUIT IGNITION COIL #3 PRIMARY CIRCUIT IGNITION COIL #4 PRIMARY CIRCUIT IGNITION COIL #5 PRIMARY CIRCUIT INJECTOR #1 CONTROL CIRCUIT INJECTOR #2 CONTROL CIRCUIT INJECTOR #3 CONTROL CIRCUIT INJECTOR #4 CONTROL CIRCUIT INJECTOR #5 CONTROL CIRCUIT INJECTOR #6 CONTROL CIRCUIT INJECTOR #7 CONTROL CIRCUIT INJECTOR #8 CONTROL CIRCUIT INJECTOR #9 CONTROL CIRCUIT INJECTOR #10 CONTROL CIRCUIT INTAKE AIR TEMP SENSOR VOLTAGE HIGH INTAKE AIR TEMP SENSOR VOLTAGE LOW INTERMITTENT LOSS OF CMP OR CKP

Test #

MIL Code

DTC HEX 69 9C 7E 1F 1E 11 8C 21 A1 BB A0 71 12 96 95 97 65 77 76 0B 8E 8D A9 A8 A7 AB 19 2B 2A 29 4C 4D 15 14 13 3D 45 46 4F 50 37 38 3A 39 9D

Scan Tool P 0141 P 0137 P 0138 P 0118 P 0117 P 0403 P 0400 N/A P 0455 P 1486 P 0442 P 0441 P 0443 N/A N/A N/A N/A P 0171 P 0172 N/A P 1757 P 1756 P 1762 P 1763 P 1764 P 0748 P 0505 P 0351 P 0351 P 0351 P 0351 P 0351 P 0201 P 0202 P 0203 P 0204 P 0205 P 0206 P 0207 P 0208 P 0209 P 0210 P 0113 P 0112 P 1391

TC-105 TC-156 TC-126 TC-31 TC-30 TC-17 TC-140 ** TC-161 TC-187 TC-160 TC-113 TC-18 TC-150 TC-149 TC-151 TC-101 TC-119 TC-118 TC-11 TC-142 TC-141 TC-169 TC-168 TC-167 TC-171 TC-25 TC-43 TC-42 TC-41 TC-76 TC-77 TC-21 TC-21 TC-21 TC-21 TC-21 TC-21 TC-21 TC-21 TC-21 TC-21 TC-58 TC-57 TC-157

21 21 21 22 22 32 68 17 31 31 31 31 31 42 42 42 42 51 52 41 45 45 45 45 45 45 25 43 43 43 43 43 27 27 27 27 27 27 27 27 27 27 23 23 11

T R O U B L E C O D E T E S T S

** = Trouble code information on last page of DTC test. 71

T R O U B L E C O D E T E S T S

DTC TEST

CHECKING THE SYSTEM FOR DIAGNOSTIC TROUBLE CODES (DTCs)

TROUBLE CODE DESCRIPTION [SDD] INTERNAL CONTROLLER FAILURE LEAK DETECT PUMP SW OR MECHANICAL FAULT LEAK DETECTION PUMP SOLENOID CIRCUIT LOW OUTPUT SPD SENSOR RPM, ABOVE 15 MPH * MAP SENSOR VOLTAGE TOO HIGH * MAP SENSOR VOLTAGE TOO LOW MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT * MULTIPLE CYLINDER MIS-FIRE NO 5 VOLTS TO MAP SENSOR NO ASD RELAY OUTPUT VOLTAGE AT PCM NO CAM SIGNAL AT PCM NO CHANGE IN MAP FROM START TO RUN NO CRANK REFERENCE SIGNAL AT PCM NO TEMP RISE SEEN FROM INTAKE HEATERS NO VEHICLE SPEED SENSOR SIGNAL O/D SWITCH PRESSED (LO) MORE THAN 5 MIN P/N SWITCH STUCK IN PARK OR IN GEAR PCM FAILURE EEPROM WRITE DENIED PCM FAILURE SPI COMMUNICATIONS PCM FAILURE SRI MILE NOT STORED POST-CATALYST O2 SEN SHORTED TO GROUND POST-CATALYST O2 SEN SHORTED TO VOLTAGE POST-CATALYST O2S HEATER FAILURE POST-CATALYST O2 SLOW RESPONSE POWER STEERING SWITCH FAILURE PRE-CATALYST O2 SENSOR SLOW RESPONSE RAD FAN CONTROL RELAY CIRCUIT RIGHT BANK FUEL SYSTEM LEAN RIGHT BANK FUEL SYSTEM RICH RIGHT BANK UPSTRM O2S SHORTED TO GROUND RIGHT O2 SENSOR SHORTED TO VOLTAGE RIGHT UPSTREAM O2 SENSOR HEATER FAILURE RIGHT UPSTREAM O2 SENSOR SLOW RESPONSE SPEED CONTROL POWER RELAY CIRCUIT SPEED CONTROL SOLENOIDS CIRCUITS SPEED CONTROL SWITCH ALWAYS LOW TARGET IDLE NOT REACHED * THROTTLE POSITION SENSOR VOLTAGE HIGH * THROTTLE POSITION SENSOR VOLTAGE LOW TORQ CONV CLU, NO RPM DROP AT LOCKUP TORQUE CONVERTER CLUCTH SOLENOID/TRANS RELAY CKT * TPS VOLTAGE DOES NOT AGREE WITH MAP

Test #

MIL Code

DTC HEX 02 B8 B7 A6 25 24 BA 6A 87 2C 01 27 28 A2 23 BC 72 31 44 30 90 93 BD 9F 73 68 0E 79 78 B5 42 7C 7A 52 0F 57 8A 1B 1A 94 0C 84

Scan Tool P 0601 P 1494 P 1495 P 0720 P 0108 P 0107 P 1398 P 0300 P 1296 N/A P 0340 P 1297 N/A P 1291 P 0500 N/A P 1899 P 1698 P 0600 P 1697 P 0143 P 0144 P 0147 P 0145 P 0551 P 0139 P 1491 P 0174 P 0175 P 0151 P 0152 P 0155 P 0153 N/A N/A N/A P 1294 P 0123 P 0122 P 0740 P 0743 P 0121

** TC-184 TC-183 TC-166 TC-37 TC-36 TC-186 TC-106 TC-135 TC-44 TC-1 TC-39 TC-40 TC-162 TC-35 TC-188 TC-114 TC-49 ** TC-48 TC-144 TC-147 TC-189 TC-159 TC-115 TC-104 TC-14 TC-121 TC-120 TC-181 TC-66 TC-124 TC-122 TC-15 TC-15 TC-87 TC-138 TC-27 TC-26 TC-148 TC-12 TC-132

53 31 31 15 14 14 11 43 14 42 54 13 11 23 15 45 37 63 53 62 21 21 21 21 65 21 35 51 52 21 21 21 21 77 34 34 25 24 24 37 37 24

* = These DTC’s can be set by Low Fuel Level, add fuel to 1/4 tank and test for DTC to set again. ** = Trouble code information on last page of DTC test.

72

DTC TEST

CHECKING THE SYSTEM FOR DIAGNOSTIC TROUBLE CODES (DTCs)

TROUBLE CODE DESCRIPTION [SDD] TRANS 12 VOLT SUPPLY RELAY CNTRL CIRCUIT TRANS 3-4 SOLENOID/TRANS RELAY CKTS TRANS TEMP SENSOR VOLTAGE TOO HIGH TRANS TEMP SENSOR VOLTAGE TOO LOW TRANS TEMP SENSOR, NO TEMP RISE AFTER START (Left) UPSTREAM O2 SENSOR HEATER FAILURE (Left) UPSTREAM O2S VOLTAGE SHORTED TO GROUND (Left) UPSTREAM O2 SENSOR SLOW RESPONSE (Left) UPSTREAM O2 SENSOR SHORTED TO VOLTAGE

Test #

MIL Code

DTC HEX AD 32 4B 4A A4 67 9B 66 3E

Scan Tool P 1765 P 0753 P 0713 P 0712 P 0711 P 0135 P 0131 P 0133 P 0132

TC-173 TC-50 TC-75 TC-74 TC-164 TC-103 TC-155 TC-102 TC-62

45 45 37 37 37 21 21 21 21

T R O U B L E C O D E T E S T S

For an ENGINE IS COLD TOO LONG trouble code, the engine does not warm to 176°F while driving for 20 minutes after start. See the service manual for cooling system repair (thermostat). For an INTERNAL CONTROLLER FAILURE trouble code, replace the powertrain control module and go to Verification TEST VER-2A. For a PCM FAILURE SPI COMMUNICATIONS trouble code, replace the powertrain control module and go to Verification TEST VER-2A. * These DTC’s can be set by Low Fuel Level, add fuel to
1 4

tank and test for DTC to set again.

73

T TEST TC-1A REPAIRING - NO CAM SIGNAL AT PCM R O Perform DTC TEST Before Proceeding U ZJ BODY ALL OTHERS B L E C O D E T E S T S

FIG. 1
ALL EXCEPT 8.0L ENGINE 8.0L ENGINE

FIG. 2

74

TEST TC-1A

REPAIRING - NO CAM SIGNAL AT PCM

Perform DTC TEST Before Proceeding

START TEST TC-1A.

USING THE DRB, ERASE TROUBLE CODES.

T R O U B L E C O D E

ATTEMPT TO START THE ENGINE. IF IT DOES NOT START, CRANK FOR AT LEAST 15 SECONDS.

USING THE DRB, READ ALL TROUBLE CODES.

DID THE CODE "NO CAM SIGNAL AT PCM" RETURN?

NO

PERFORM TEST TC-1C.

YES

T E S T S

KEY OFF, DISCONNECT THE CAMSHAFT POSITION SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE CMP SENSOR...

GROUND CIRCUIT FROM THE CMP SENSOR CONNECTOR TO GROUND. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN CMP SENSOR GROUND CIRCUIT TO THE HARNESS SPLICE.*

YES

TURN IGNITION ON.

USING A VOLTMETER, MEASURE THE 5-VOLT SUPPLY CIRCUIT. FIG. 1 OR 2

IS THE VOLTAGE ABOVE 4.0 VOLTS?

NO

REPAIR THE OPEN 5-VOLT SUPPLY CIRCUIT.*

YES

CONNECT ONE END OF A JUMPER WIRE TO THE CMP SENSOR SIGNAL CIRCUIT. FIG. 1 OR 2

WITH THE DRB MONITOR THE CMP COUNT WHILE TAPPING THE OTHER END OF THE JUMPER TO SENSOR GROUND.

DOES THE CURRENT CMP COUNT CHANGE?

YES

PERFORM TEST TC-1B.

NO

CONTINUE TEST TC-1A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
75

T TEST TC-1A R O U ZJ BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - NO CAM SIGNAL AT PCM

FIG. 1
ALL OTHERS

FIG. 2
76

TEST TC-1A

CONTINUED - REPAIRING - NO CAM SIGNAL AT PCM

TEST TC-1A CONTINUED FROM THE PREVIOUS PAGE.

TURN IGNITION OFF.

T R O U B L E C O D E

DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTORS.** SEE GENERAL INFO 4.1

T E S T S
CIRCUIT FROM THE CMP SENSOR CONNECTOR TO THE PCM. FIG. 1 OR 2 YES

USE AN OHMMETER IN THE FOLLOWING STEPS, MEASURE THE RESISTANCE OF THE CMP SENSOR SIGNAL...

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN CMP SENSOR SIGNAL CIRCUIT.*

MEASURE THE RESISTANCE BETWEEN THE CMP SENSOR SIGNAL CIRCUIT...

AND THE CMP SENSOR GROUND CIRCUIT AT THE CMP SENSOR CONNECTOR. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE CMP SENSOR SIGNAL CIRCUIT FOR A SHORT TO THE SENSOR GROUND.*

NO

MEASURE THE RESISTANCE BETWEEN THE CMP SENSOR SIGNAL CIRCUIT...

AND GROUND AT THE CMP SENSOR CONNECTOR. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE CMP SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

MEASURE THE RESISTANCE BETWEEN THE CMP SENSOR SIGNAL CIRCUIT AND THE...

5-VOLT SUPPLY CIRCUIT AT THE CMP SENSOR CONNECTOR. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE CMP SENSOR SIGNAL CIRCUIT FOR A SHORT TO THE 5-VOLT SUPPLY CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
77

T TEST TC-1B REPAIRING - NO CAM SIGNAL AT PCM R O Perform TEST TC-1A Before Proceeding U B L E C O D E T E S T S

FIG. 1

78

TEST TC-1B

REPAIRING - NO CAM SIGNAL AT PCM

Perform TEST TC-1A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-1B.

TURN IGNITION OFF.

IS THE VEHICLE EQUIPPED WITH A 8.0 LITER ENGINE?

YES

CONTINUE TEST TC-1B ON THE NEXT PAGE.

NO

REMOVE DISTRIBUTOR CAP AND ROTOR. FIG. 1

INSPECT THE PULSE RING FOR DAMAGE OR MISALIGNMENT.

IS THE PULSE RING OKAY?

NO

REPAIR OR REPLACE THE DISTRIBUTOR AND OR THE PULSE RING AS NECESSARY.*

YES

REPLACE THE CAMSHAFT POSITION SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
79

T TEST TC-1B R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - NO CAM SIGNAL AT PCM

FIG. 1

80

TEST TC-1B

CONTINUED - REPAIRING - NO CAM SIGNAL AT PCM

T R O U B L E C O D E T E S T S

TEST TC-1B CONTINUED FROM THE PREVIOUS PAGE.

REMOVE THE CAMSHAFT POSITION SENSOR. FIG. 1

INSPECT THE CAMSHAFT SPROCKET PER SERVICE MANUAL INSTRUCTIONS.

IS THE CAMSHAFT SPROCKET OK?

YES

REPLACE THE CAMSHAFT POSITION SENSOR.*

NO

REPAIR AS NECESSARY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
81

T TEST TC-1C REPAIRING - NO CAM SIGNAL AT PCM R O Perform TEST TC-1A Before Proceeding U B L E C O D E T E S T S

FIG. 1
ZJ BODY ALL OTHERS

82

TEST TC-1C

REPAIRING - NO CAM SIGNAL AT PCM

Perform TEST TC-1A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-1C.

ATTEMPT TO START THE ENGINE, IF NOT ALREADY RUNNING.

DOES THE ENGINE START?

NO

PERFORM NO START TEST NS-SEL.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO GEN INFO 3.3.2 FOR INFORMATION ON INACTIVE TROUBLE CODES.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
83

T TEST TC-5A REPAIRING - CHARGING SYSTEM VOLTAGE TOO LOW R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

AB, AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2
84

FIG. 3

TEST TC-5A

REPAIRING - CHARGING SYSTEM VOLTAGE TOO LOW

Perform DTC TEST Before Proceeding

START TEST TC-5A.

NOTE: BATTERY MUST BE FULLY CHARGED.

T R O U B L E C O D E

NOTE: GENERATOR BELT TENSION AND CONDITION MUST BE CHECKED BEFORE CONTINUING.

START ENGINE, WITH DRB, READ THE TARGET CHARGING VOLTAGE.

IS THE TARGET CHARGING VOLTAGE ABOVE 15.1 VOLTS?

NO

CONTINUE TEST TC-5A ON THE NEXT PAGE.

YES

T E S T S

WITH THE DRB READ THE BATTERY TEMP SENSOR TEMPERATURE.

USING A THERMOMETER, MEASURE UNDER HOOD TEMPERATURE.

IS THE TEMPERATURE WITHIN 10F DEG. OF BATTERY TEMPERATURE?

YES

CONTINUE TEST TC-5A ON THE NEXT PAGE.

NO

DISCONNECT THE BATTERY TEMPERATURE SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

CONNECT A JUMPER ACROSS THE TERMINALS OF THE BATTERY TEMPERATURE SENSOR. FIG. 1, 2 OR 3

WITH THE DRB, READ BATTERY TEMPERATURE SENSOR VOLTAGE.

IS THE VOLTAGE READING EQUAL TO ZERO?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPLACE THE BATTERY TEMPERATURE SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
85

T TEST TC-5A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - CHARGING SYSTEM VOLTAGE TOO LOW

FIG. 1

FIG. 2
86

TEST TC-5A

CONTINUED - REPAIRING - CHARGING SYSTEM VOLTAGE TOO LOW

TEST TC-5A CONTINUED FROM THE PREVIOUS PAGE.

YES IS THIS A DIESEL?

DOES THE ENGINE RUN?

NO

PERFORM TEST TC-40A.

T R O U B L E C O D E T E S T S

NO

YES

CAUTION: IF THIS IS A DIESEL, DO NOT DO ANY CHARGING SYSTEM TEST WITH INTAKE HEATERS ON.

USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE VOLTAGE BETWEEN THE GEN B+ TERMINAL AND THE BATTERY (+) POST. FIG. 1

CAUTION: ENSURE ALL WIRES ARE CLEAR OF THE ENGINE’S MOVING PARTS.

IS THE VOLTAGE ABOVE 0.4 VOLT?

YES

REPAIR THE B (+) CIRCUIT FOR HIGH RESISTANCE BETWEEN THE GENERATOR AND THE BATTERY.*

NO

IGNITION KEY OFF. USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE VOLTAGE BETWEEN THE GENERATOR CASE AND BATTERY (-) POST. FIG. 2

CAUTION: ENSURE ALL WIRES ARE CLEAR OF THE ENGINE’S MOVING PARTS.

START THE ENGINE.

WARM THE ENGINE TO OPERATING TEMPERATURE.

IS THE VOLTAGE ABOVE 0.1 VOLT?

YES

REPAIR GENERATOR GROUND FOR HIGH RESISTANCE, GENERATOR CASE TO BATTERY (-) SIDE.*

NO

TURN ON ALL ACCESSORIES, MANUALLY SET ENGINE SPEED TO 1600 RPM. WITH THE DRB...

READ TARGET CHARGING AND CHARGING VOLTAGE. COMPARE THE TWO READINGS.

IS THERE MORE THAN A 1.0 VOLT DIFFERENCE?

YES

REPAIR OR REPLACE THE GENERATOR AS NECESSARY.*

NO

ALLOW THE ENGINE TO RETURN TO IDLE SPEED.

TURN ENGINE OFF. (IGNITION KEY ON)

RECORD ALL DTC’S AND FREEZE FRAME DATA, NOW ERASE CODES.

CHARGING SYSTEM CHECKS OK AT THIS TIME. SEE GEN INFO 3.3.2

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
87

T TEST TC-6A REPAIRING - CHARGING SYSTEM VOLTAGE TOO HIGH R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
88

FIG. 3

TEST TC-6A

REPAIRING - CHARGING SYSTEM VOLTAGE TOO HIGH

Perform DTC TEST Before Proceeding

START TEST TC-6A.

READ FIGURE 1 TO DETERMINE WHICH TERMINAL IS THE GENERATOR FIELD DRIVER CIRCUIT.

T R O U B L E C O D E T E S T S

WITH THE DRB, ACTUATE THE GENERATOR FIELD DRIVER.

PLEASE READ FIGURE 2 TO HAVE A CLEAR UNDERSTANDING OF THIS TROUBLE CODE.

USE A VOLTMETER IN THE FOLLOWING STEP.

BACKPROBE THE GENERATOR FIELD DRIVER CIRCUIT IN BACK OF GENERATOR. FIG. 3

DOES THE VOLTAGE SHIFT LOW TO HIGH?

YES

PERFORM TEST TC-6B.

NO

WITH THE DRB, STOP THE GENERATOR FIELD DRIVER ACTUATION.

TURN IGNITION OFF.

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

DISCONNECT THE FIELD HARNESS CONNECTOR AT BACK OF THE GENERATOR.**

CONTINUE TEST TC-6A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
89

T TEST TC-6A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - CHARGING SYSTEM VOLTAGE TOO HIGH

FIG. 1

FIG. 2
90

TEST TC-6A

CONTINUED - REPAIRING - CHARGING SYSTEM VOLTAGE TOO HIGH

T R O U B L E C O D E T E S T S

TEST TC-6A CONTINUED FROM THE PREVIOUS PAGE.

USE AN OHMMETER IN THE FOLLOWING STEPS.

MEASURE THE GENERATOR FIELD DRIVER CIRCUIT FROM THE PCM CONNECTOR TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE GENERATOR FIELD DRIVER CIRCUIT SHORT TO GROUND.*

NO

MEASURE RESISTANCE OF THE GENERATOR FIELD TERMINALS AT THE GENERATOR. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR OR REPLACE THE SHORTED GENERATOR AS NECESSARY.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
91

T TEST TC-6B REPAIRING - CHARGING SYSTEM VOLTAGE TOO HIGH R O Perform TEST TC-6A Before Proceeding U AB BODY B L E C O D E T E S T S

AN AND BR BODIES

92

TEST TC-6B

REPAIRING - CHARGING SYSTEM VOLTAGE TOO HIGH

Perform TEST TC-6A Before Proceeding

START TEST TC-6B.

WITH THE DRB, STOP THE GENERATOR FIELD DRIVER ACTUATION. READ THE TARGET CHARGING VOLTAGE.

IS THE TARGET CHARGING VOLTAGE ABOVE 13.0 VOLTS?

YES

CONTINUE TEST TC-6B ON THE NEXT PAGE.

T R O U B L E C O D E

NO

WITH THE DRB, READ THE BATTERY TEMP SENSOR TEMPERATURE.

USING A THERMOMETER, MEASURE THE UNDER HOOD TEMPERATURE.

IS THE TEMPERATURE WITHIN 10F DEG. OF BATTERY TEMPERATURE?

YES

PERFORM TEST TC-153A.

NO

T E S T S

CONTINUE TEST TC-6B ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
93

T TEST TC-6B CONTINUED - REPAIRING - CHARGING SYSTEM VOLTAGE TOO HIGH R O Perform TEST TC-6A Before Proceeding U NOTES B L E C O D E T E S T S

94

TEST TC-6B

CONTINUED - REPAIRING - CHARGING SYSTEM VOLTAGE TOO HIGH

Perform TEST TC-6A Before Proceeding

T R O U B L E C O D E

TEST TC-6B CONTINUED FROM THE PREVIOUS PAGE.

START THE ENGINE.

T E S T S
WITH THE DRB, READ BOTH THE BATTERY VOLTAGE AND THE TARGET CHARGING VOLTAGE.

MANUALLY SET THE ENGINE SPEED TO 1600 RPM.

COMPARE THE "TARGET VOLTAGE" TO THE "BATTERY VOLTAGE" READING.

MONITOR VOLTAGE FOR 5 MINUTES, IF NECESSARY. LOOK FOR A 1.0 VOLT DIFFERENCE OR MORE.

WAS THERE MORE THAN A 1.0 VOLT DIFFERENCE?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

ALLOW THE ENGINE TO RETURN TO IDLE SPEED.

TURN ENGINE OFF. IGNITION KEY ON.

RECORD ALL DTC’S AND FREEZE FRAME DATA, NOW ERASE CODES.

NO TROUBLE FOUND AT THIS TIME. SEE GEN INFO 3.3.2

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
95

T TEST TC-10A REPAIRING - AUTO SHUTDOWN RELAY CONTROL CIRCUIT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
96

TEST TC-10A REPAIRING - AUTO SHUTDOWN RELAY CONTROL CIRCUIT
Perform DTC TEST Before Proceeding

START TEST TC-10A.

WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY. SEE GENERAL INFO 4.6

IS THE AUTO SHUTDOWN RELAY CLICKING?

NO

CONTINUE TEST TC-10A ON THE NEXT PAGE.

T R O U B L E C O D E

YES

THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

T E S T S

START THE ENGINE.

IS THE VEHICLE EQUIPPED WITH A DIESEL ENGINE? YES

NO

WIGGLE THE WIRING HARNESS FROM THE RELAY TO THE POWERTRAIN CONTROL MODULE.

DISCONNECT THE INTAKE AIR TEMP HEATER RELAY CONTROL WIRES. SEE GENERAL INFO 4.6

DID THE ENGINE DIE OUT WHEN WIGGLING WIRES? NO

YES

REPAIR CIRCUIT AS NECESSARY WHERE WIGGLING CAUSED THE ENGINE TO DIE OUT.*

TURN THE HEADLAMPS ON & WIGGLE THE WIRING HARNESS FROM ASD RELAY TO THE PCM.

REFER TO FIGURE 2 FOR INACTIVE TROUBLE CODE CONDITION INFORMATION.

TEST COMPLETE.*

NO DID WIGGLING CAUSE THE HEADLAMPS TO FLICKER? YES REPAIR AS NECESSARY WHERE WIGGLING CAUSED THE HEADLAMPS TO FLICKER.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
97

T TEST TC-10A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - AUTO SHUTDOWN RELAY CONTROL CIRCUIT
AN BODY

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
98

FIG. 6

TEST TC-10A CONTINUED - REPAIRING - AUTO SHUTDOWN RELAY CONTROL CIRCUIT

TEST TC-10A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE AUTO SHUTDOWN RELAY.** SEE GENERAL INFO 4.6

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CKT AT RELAY. FIG. 1, 2, 3, 4 OR 5

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.*

YES

T E S T S

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE RESISTANCE BETWEEN TERMINALS 85 AND 86 OF THE ASD RELAY. FIG. 6

IS THE RESISTANCE BELOW 100.0 OHMS?

NO

REPLACE THE AUTO SHUTDOWN RELAY.*

YES

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE GREY CONNECTOR.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE ASD RLY CONTROL CIRCUIT AT PCM TO GROUND. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE AUTO SHUTDOWN RELAY CONTROL CKT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE ASD RELAY CONTROL CIRCUIT...

FROM THE RELAY TO THE PCM. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN AUTO SHUTDOWN RELAY CONTROL CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
99

T TEST TC-11A REPAIRING - GENERATOR FIELD NOT SWITCHING PROPERLY R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
100

FIG. 3

TEST TC-11A REPAIRING - GENERATOR FIELD NOT SWITCHING PROPERLY
Perform DTC TEST Before Proceeding

START TEST TC-11A.

RECORD ALL DTC’S AND FREEZE FRAME DATA, NOW ERASE CODES.

T R O U B L E C O D E

READ FIGURE 1 TO DETERMINE WHICH TERMINAL IS THE GENERATOR FIELD DRIVER CIRCUIT.

WITH THE DRB, ACTUATE THE GENERATOR FIELD DRIVER CIRCUIT.

T E S T S
REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT, GENERATOR TO HARNESS SPLICE.*

BACKPROBE THE ASD RELAY OUTPUT CIRCUIT AT THE BACK OF THE GENERATOR. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

YES

BACKPROBE THE GEN FIELD DRIVER CIRCUIT AT THE BACK OF THE GENERATOR. FIG. 2

DOES THE VOLTAGE SHIFT FROM LOW TO HIGH?

NO

CONTINUE TEST TC-11A ON THE NEXT PAGE.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 3

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH THE DRB, READ CODES. NOTE: ACTUATOR TEST SHOULD STILL BE RUNNING.

WIGGLE WIRING HARNESS FROM THE GENERATOR TO PCM.

DOES THE GENERATOR FIELD DRIVER CIRCUIT CODE RETURN?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED PROBLEM TO APPEAR.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-3A.

**Check connectors - Clean / repair as necessary.
101

T TEST TC-11A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - GENERATOR FIELD NOT SWITCHING PROPERLY

FIG. 1

FIG. 2

FIG. 3
102

FIG. 4

TEST TC-11A CONTINUED - REPAIRING - GENERATOR FIELD NOT SWITCHING PROPERLY

TEST TC-11A CONTINUED FROM THE PREVIOUS PAGE.

READ FIGURE 1 TO DETERMINE WHICH TERMINAL IS THE GENERATOR FIELD DRIVER CIRCUIT.

T R O U B L E C O D E

WITH THE DRB, STOP THE GENERATOR FIELD DRIVER ACTUATION.

TURN IGNITION OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

DISCONNECT THE GEN FIELD HARNESS CONNECTOR AT BACK OF THE GENERATOR.** SEE GENERAL INFO 4.2

T E S T S

USE AN OHMMETER IN THE FOLLOWING STEPS.

MEASURE RESISTANCE OF THE GEN FIELD DRIVER CKT, GEN CONN TO PCM CONN. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN GENERATOR FIELD DRIVER CIRCUIT, GENERATOR TO PCM.*

YES

MEASURE THE RESISTANCE ACROSS THE GENERATOR FIELD TERMINALS AT THE GENERATOR. FIG. 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE GENERATOR AS NECESSARY.*

YES

MEASURE THE GEN FIELD DRIVER CIRCUIT AT GENERATOR HARNESS CONN TO GROUND. FIG. 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE GENERATOR FIELD DRIVER CIRCUIT, SHORT TO GROUND.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-3A.

**Check connectors - Clean / repair as necessary.
103

T TEST TC-12A REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
104

TEST TC-12A REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT
Perform DTC TEST Before Proceeding

START TEST TC-12A.

DOES THIS VEHICLE HAVE A 4 SPEED ELECTRONIC TRANSMISSION?

NO

PERFORM TEST TC-12E.

T R O U B L E C O D E

YES

IS THE TRANS 12-VOLT SUPPLY RELAY CONTROL CIRCUIT CODE SET?

YES

PERFORM TEST TC-173A.

NO

T E S T S

WITH THE DRB, PERFORM THE TCC SYSTEM TESTS.

DID THE ENGINE STALL?

NO

CONTINUE TEST TC-12A ON THE NEXT PAGE.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THIS CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH THE DRB, CLEAR CODES. START THE ENGINE.

WHILE READING DTC’S WITH THE DRB, WIGGLE THE WIRING HARNESS FROM THE SOLENOID TO THE PCM.

DOES THE TCC SOLENOID CONTROL CIRCUIT FAULT CODE APPEAR?

YES

REPAIR THE WIRING AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
105

T TEST TC-12A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
106

FIG. 4

- REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS TEST TC-12A CONTINUED RELAY CKT

T R O U B L E C O D E T E S T S

TEST TC-12A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE TRANS SOLENOID PACK CONNECTOR.** SEE GENERAL INFO 4.2

KEY ON. WITH THE DRB, ACTUATE THE TRANS CONTROL RELAY.

MEASURE THE VOLTAGE AT THE TRANS RELAY OUTPUT CIRCUIT. FIG. 1, 2, 3 OR 4

DOES THE VOLTAGE FLUCTUATE FROM 0 VOLT TO OVER 10.0 VOLTS?

NO

PERFORM TEST TC-12B.

YES

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE WHITE CONNECTOR.**

KEY ON. MEASURE THE VOLTAGE AT THE TCC SOLENOID CONTROL CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

PERFORM TEST TC-12D.

NO

CONTINUE TEST TC-12A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
107

T TEST TC-12A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
108

FIG. 4

- REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS TEST TC-12A CONTINUED RELAY CKT

TEST TC-12A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF. MEASURE THE RESISTANCE BETWEEN THE TCC SOLENOID CONTROL CIRCUIT...

T R O U B L E C O D E T E S T S

AT THE PCM CONNECTOR AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE TCC SOLENOID CONTROL CIRCUIT SHORTED TO GROUND.*

NO

CONNECT THE SOLENOID PACK CONNECTOR.

MEASURE THE RESISTANCE BETWEEN THE TCC SOLENOID CONTROL CIRCUIT...

AT THE PCM CONNECTOR AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

RELACE THE SOLENOID AND HARNESS ASSEMBLY.*

NO

CONTINUE TEST TC-12A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
109

T TEST TC-12A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
110

FIG. 4

- REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS TEST TC-12A CONTINUED RELAY CKT

T R O U B L E C O D E T E S T S

TEST TC-12A CONTINUED FROM THE PREVIOUS PAGE.

REMOVE THE TRANS CONTROL RELAY.** SEE GENERAL INFO 4.6

MEASURE THE RESISTANCE BETWEEN THE TRANS CONTROL RELAY OUTPUT CIRCUIT AT THE RELAY...

AND THE TCC SOLENOID CONTROL CIRCUIT AT THE PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BETWEEN 26.0 AND 40.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

IS THE RESISTANCE ABOVE 40.0 OHMS?

NO

PERFORM TEST TC-12C.

YES

CONTINUE TEST TC-12A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
111

T TEST TC-12A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
112

FIG. 4

- REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS TEST TC-12A CONTINUED RELAY CKT

T R O U B L E C O D E T E S T S

TEST TC-12A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE TRANS SOLENOID PACK CONNECTOR.** SEE GENERAL INFO 4.2

MEASURE THE RESISTANCE OF THE TCC SOLENOID CONTROL CIRCUIT...

FROM THE PCM CONNECTOR TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN TCC SOLENOID CONTROL CIRCUIT.*

YES

REPLACE THE SOLENOID AND HARNESS ASSEMBLY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
113

T TEST TC-12B REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT R O Perform TEST TC-12A Before Proceeding U AB BODY AN BODY B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
114

FIG. 4

TEST TC-12B REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT
Perform TEST TC-12A Before Proceeding

START TEST TC-12B.

REMOVE THE TRANS CONTROL RELAY.** SEE GENERAL INFO 4.6

T R O U B L E C O D E T E S T S

KEY OFF. MEASURE THE RESISTANCE BETWEEN THE TRANS CONTROL RELAY OUTPUT CIRCUIT...

AT THE RELAY CONNECTOR AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE TRANS CONTROL RELAY OUTPUT CIRCUIT SHORTED TO GROUND.*

NO

MEASURE THE RESISTANCE OF THE TRANS CONTROL RELAY OUTPUT CIRCUIT...

FROM THE RELAY CONNECTOR TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN TRANS CONTROL RELAY OUTPUT CIRCUIT.*

NO

KEY ON, MEASURE THE VOLTAGE AT THE FUSED B(+) CIRCUIT IN THE RELAY CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+) FEED TO THE TRANS CONTROL RELAY.*

YES

REPLACE THE TRANS CONTROL RELAY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
115

T TEST TC-12C CONTINUED - REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT R Perform TEST TC-12A Before Proceeding O U AB BODY AN BODY B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
116

FIG. 4

- REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS TEST TC-12C CONTINUED RELAY CKT Perform TEST TC-12A Before Proceeding

START TEST TC-12C.

DISCONNECT THE TRANS SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

DISCONNECT ALL PCM CONNECTORS.** SEE GENERAL INFO 4.1

T R O U B L E C O D E T E S T S

MEASURE AND RECORD THE RESISTANCES BETWEEN THE TCC SOLENOID CONTROL CIRCUIT...

AND ALL OTHER CIRCUITS IN THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS BETWEEN ANY TWO CIRCUITS?

REPAIR TCC SOLENOID YES CONTROL CKT SHORTED TO CIRCUIT(S) THAT MEASURED BELOW 5.0 OHMS.*

NO

REPLACE THE SOLENOID HARNESS INSIDE THE TRANSMISSION AND THE SOLENOID PACK.*

CONNECT ALL DISCONNECTED CONNECTORS.

WITH THE DRB, PERFORM TCC SYSTEM TEST.

DID THE VEHICLE STALL?

NO REPLACE THE PCM.*

YES

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
117

T TEST TC-12D REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT R O Perform TEST TC-12A Before Proceeding U NOTES B L E C O D E T E S T S

118

TEST TC-12D REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT
Perform TEST TC-12A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-12D.

REPAIR TCC SOLENOID CONTROL CIRCUIT SHORTED TO VOLTAGE.*

CONNECT ALL DISCONNECTED CONNECTORS.

WITH THE DRB, PERFORM TCC SYSTEM TEST.

DID THE VEHICLE STALL?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
119

T TEST TC-12E REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT R O Perform TEST TC-12A Before Proceeding U AB AND XJ BODIES WITH 3 SPD RH TRANS B L E C O D E T E S T S

AB BODY WITH 3 SPD RH TRANS

FIG. 1
AB BODY WITH 3 SPD RH TRANS

FIG. 2
120

TEST TC-12E REPAIRING - TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT
Perform TEST TC-12A Before Proceeding

START TEST TC-12E.

DISCONNECT THE TRANSMISSION SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E

IGNITION KEY ON.

MEASURE THE VOLTAGE AT THE FUSED IGNITION SWITCH OUTPUT CIRCUIT. FIG. 1

IS THE VOLTAGE BELOW 10.0 VOLTS?

YES

REPAIR THE OPEN FUSED IGNITON SWITCH OUTOUT.*

NO

T E S T S

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.**

MEASURE THE RESISTANCE BETWEEN THE TCC SOLENOID CONTROL CIRCUIT...

AND GROUND. IS THE RESISTANCE BELOW 5.0 OHMS? FIG. 1 NO YES

REPAIR THE TCC SOLENOID CONTROL CIRCUIT SHORTED TO GROUND.*

MEASURE THE RESISTANCE OF THE TCC SOLENOID CONTROL CIRCUIT FROM...

THE POWERTRAIN CONTROL MODULE TO THE TCC SOLENOID CONNECTOR. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN TCC SOLENOID CONTROL CIRCUIT.*

YES

CONNECT THE TCC SOLENOID CONNECTOR. TURN KEY ON.

MEASURE THE VOLTAGE AT THE TCC SOLENOID CONTROL CIRCUIT AT PCM CONNECTOR. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPLACE THE TCC SOLENOID.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
121

T TEST TC-14A REPAIRING - RAD FAN CONTROL RELAY CIRCUIT R O Perform DTC TEST Before Proceeding U AN BODY XJ BODY B L E C O D E T E S T S

AN BODY

XJ BODY

FIG. 1

FIG. 2

FIG. 3
122

FIG. 4

TEST TC-14A REPAIRING - RAD FAN CONTROL RELAY CIRCUIT
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-14A.

WITH THE DRB, ACTUATE THE RADIATOR FAN RELAY. FIG. 1 OR 2

IS THE RADIATOR FAN RELAY CLICKING?

NO

CONTINUE TEST TC-14A ON THE NEXT PAGE.

YES

THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 3

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WIGGLE THE WIRING HARNESS FROM THE RELAY TO THE POWERTRAIN CONTROL MODULE.

NOTE: THE DRB MUST STILL BE ACTUATING THE RADIATOR FAN RELAY.

DID THE WIGGLING INTERRUPT THE CLICKING?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED THE CLICKING TO BE INTERRUPTED.*

NO

REFER TO FIG. 4 FOR INACTIVE TROUBLE CODE CONDITION INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
123

T TEST TC-14A R O U AN BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - RAD FAN CONTROL RELAY CIRCUIT

FIG.1
XJ BODY

FIG. 2
AN BODY XJ BODY

FIG. 3

FIG. 4
124

FIG. 5

TEST TC-14A CONTINUED - REPAIRING - RAD FAN CONTROL RELAY CIRCUIT

TEST TC-14A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE RADIATOR FAN RELAY.** FIG. 1 OR 2

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CIRCUIT. FIG. 1 OR 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.*

YES

T E S T S

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE RESISTANCE BETWEEN TERMINALS 85 AND 86 OF THE RAD FAN RELAY. FIG. 3

IS THE RESISTANCE BELOW 100.0 OHMS?

NO

REPLACE THE RADIATOR FAN RELAY.*

YES

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE GREY CONNECTOR.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE RAD FAN RELAY CONTROL CKT AT PCM TO GROUND. FIG. 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE RADIATOR FAN RELAY CONTROL CKT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE THE RAD FAN RELAY CONTROL CIRCUIT...

FROM THE RELAY TO THE PCM. FIG. 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN RADIATOR FAN RELAY CONTROL CKT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
125

T TEST TC-15A REPAIRING - SPEED CONTROL SOLENOID CIRCUITS OR SPEED CONTROL POWER RELAY CIRCUITS R Perform DTC TEST Before Proceeding O U B L E C O D E T E S T S

ALL OTHERS

FIG. 1
ZJ BODY

FIG. 2

FIG. 3
126

- SPEED CONTROL SOLENOID CIRCUITS OR SPEED CONTROL POWER T TEST TC-15A REPAIRING RELAY CIRCUITS R Perform DTC TEST Before Proceeding

START TEST TC-15A.

WITH DRB, READ, RECORD AND CLEAR ALL FAULTS. IF S/C FAULTS EXISTS, THE PCM WILL...

NOT SUPPLY POWER TO THE S/C SERVOS.

START ENGINE.

O U B L E C O D E

WITH THE DRB, MONITOR THE S/C ON/OFF SWITCH STATE.

PRESS THE S/C ON/OFF SWITCH TO ON AND OFF WHILE MONITORING DISPLAY.

DID THE SPEED CONTROL ON/OFF SWITCH STATE CHANGE ON THE DRB DISPLAY? NO

YES

PERFORM TEST TC-15B.

T E S T S

DISCONNECT THE S/C SWITCH.** SEE GENERAL INFO 4.7

USING AN OHMMETER, MEASURE RESISTANCE OF THE S/C SWITCH. FIG. 2 OR 3

DOES THE S/C SWITCH RESISTANCE MATCH CHART IN FIGURE 2 OR 3?

NO

REPLACE THE S/C SWITCH.*

YES

WITH THE S/C SWITCH ON, DISCONNECT THE SPEED CONTROL SERVO 4-WAY CONNECTOR.** SEE GENERAL INFO 4.2

NOTE: ENSURE THE BRAKE PEDAL IS NOT DEPRESSED DURING THE FOLLOWING STEPS.

WITH THE DRB, ACTUATE THE S/C VENT SOLENOID.

MEASURE THE SWITCHED SPEED CONTROL POWER SUPPLY CIRCUIT AT S/C SERVO CONNECTOR. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

PERFORM TEST TC-15B.

NO

PERFORM TEST TC-15C.

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
127

T TEST TC-15B REPAIRING - SPEED CONTROL SOLENOID CIRCUITS OR SPEED CONTROL POWER RELAY CIRCUIT R Perform TEST TC-15A Before Proceeding O U AB, AN AND XJ BODIES B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
128

FIG. 4

- SPEED CONTROL SOLENOID CIRCUITS OR SPEED CONTROL POWER T TEST TC-15B REPAIRING RELAY CIRCUIT R Perform TEST TC-15A Before Proceeding

START TEST TC-15B.

NOTE: ENSURE THE BRAKE PEDAL IS NOT DEPRESSED DURING THE FOLLOWING STEPS.

O U B L E C O D E T E S T S

USING AN OHMMETER, MEASURE THE S/C GROUND CIRCUIT. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN GROUND CIRCUIT.*

YES

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

RECONNNECT SPEED CONTROL SERVO 4-WAY CONNECTOR. SEE GENERAL INFO 4.2

WITH AN OHMMETER, MEASURE THE RESISTANCE FROM THE 12-VOLT POWER SUPPLY...

TO THE SPEED CONTROL VENT SOLENOID CONTROL FROM PCM CONN. FIG. 2, 3 OR 4

IS THE RESISTANCE BETWEEN 35.0 OHMS AND 55.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

CONTINUE TEST TC-15B ON THE NEXT PAGE.

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
129

T TEST TC-15B CONTINUED - REPAIRING - SPEED CONTROL SOLENOID CIRCUITS OR SPEED CONTROL POWER RELAY CIRCUIT R O U AB, AN AND XJ BODIES B L E C O D E T E S T S
FIG. 1
BR BODY

FIG. 2
ZJ BODY

FIG. 3
130

- REPAIRING - SPEED CONTROL SOLENOID CIRCUITS OR SPEED TEST TC-15B CONTINUED CONTROL POWER RELAY CIRCUIT

TEST TC-15B CONTINUED FROM THE PREVIOUS PAGE.

T R O U B L E C O D E T E S T S

WITH AN OHMMETER, MEASURE THE RESISTANCE FROM...

12-VOLT POWER SUPPLY TO SPEED CONTROL VACCUUM SOLENOID CONTROL. FIG. 1, 2 OR 3

IS THE RESISTANCE BETWEEN 35.0 OHMS AND 55.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

WITH AN OHMMETER, MEASURE THE S/C VACUUM SOLENOID CONTROL CIRCUIT. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR SPEED VACUUM CONTROL

THE OPEN CONTROL SOLENOID CIRCUIT.*

YES

WITH AN OHMMETER, MEASURE THE S/C VENT SOLENOID CONTROL CIRCUIT. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN SPEED CONTROL VENT SOLENOID CONTROL CIRCUIT.*

YES

REPLACE THE SPEED CONTROL SERVO.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
131

T TEST TC-15C REPAIRING - SPEED CONTROL SOLENOID CIRCUITS OR SPEED CONTROL POWER RELAY CIRCUIT R Perform TEST TC-15A Before Proceeding O U AB BODY B L E C O D E T E S T S
FIG. 1
AN AND XJ BODIES BR BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
132

- SPEED CONTROL SOLENOID CIRCUITS OR SPEED CONTROL POWER T TEST TC-15C REPAIRING RELAY CIRCUIT R Perform TEST TC-15A Before Proceeding

START TEST TC-15C.

DISCONNECT THE BRAKE SWITCH CONNECTOR. SEE GENERAL INFO 4.7

O U B L E C O D E T E S T S

USING A VOLTMETER, MEASURE THE BRAKE SWITCH OUTPUT...

CIRCUIT AT THE BRAKE SWITCH CONNECTOR. FIG. 2, 3, 4 OR 5

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

PERFORM TEST TC-15D.

YES

WITH AN OHMMETER, MEASURE THE S/C BRAKE SWITCH OUTPUT CIRCUIT...

FROM THE SPEED CONTROL SERVO 4-WAY CONNECTOR SWITCHED S/C POWER SUPPLY....

TO THE BRAKE SWITCH CONNECTOR SWITCHED S/C BRAKE SWITCH OUTPUT CIRCUIT. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE BRAKE SWITCH.*

NO

REPAIR THE OPEN S/CBRAKE SWITCH OUTPUT CIRCUIT.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
133

T TEST TC-15D REPAIRING - SPEED CONTROL SOLENOID CIRCUITS OR SPEED CONTROL POWER RELAY CIRCUIT R Perform TEST TC-15C Before Proceeding O U AB BODY AN AND XJ BODIES B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
134

FIG. 4

- SPEED CONTROL SOLENOID CIRCUITS OR SPEED CONTROL POWER T TEST TC-15D REPAIRING RELAY CIRCUIT R Perform TEST TC-15C Before Proceeding

O U B L E C O D E T E S T S

START TEST TC-15D.

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

WITH AN OHMMETER, MEASURE THE SPEED CONTROL POWER SUPPLY CIRCUIT...

FROM THE PCM PIN C11 TO BRAKE SWITCH CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN SPEED CONTROL POWER SUPPLY CIRCUIT.*

135

T TEST TC-16A REPAIRING - A/C CLUTCH RELAY CIRCUIT R O Perform DTC TEST Before Proceeding U ALL BODIES B L E C O D E T E S T S

FIG. 1
136

FIG. 2

TEST TC-16A REPAIRING - A/C CLUTCH RELAY CIRCUIT
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-16A.

WITH THE DRB, ACTUATE THE A/C CLUTCH RELAY.

IS THE A/C CLUTCH RELAY CLICKING?

NO

CONTINUE TEST TC-16A ON THE NEXT PAGE.

YES

THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WIGGLE THE WIRING HARNESS FROM THE RELAY TO THE POWERTRAIN CONTROL MODULE.

NOTE: THE DRB MUST STILL BE ACTUATING THE A/C CLUTCH RELAY.

DID THE WIGGLING INTERRUPT THE CLICKING?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED THE CLICKING TO BE INTERRUPTED.*

NO

REFER TO FIGURE 2 FOR INACTIVE TROUBLE CODE CONDITION INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
137

T TEST TC-16A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - A/C CLUTCH RELAY CIRCUIT
AN BODY

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
138

FIG. 6

TEST TC-16A CONTINUED - REPAIRING - A/C CLUTCH RELAY CIRCUIT

TEST TC-16A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE A/C CLUTCH RELAY.** SEE GENERAL INFO 4.6

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CIRCUIT. FIG. 1, 2, 3, 4 OR 5

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.*

YES

T E S T S

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE RESISTANCE BETWEEN TERMINALS 85 AND 86 OF THE A/C CLUTCH RELAY. FIG. 6

IS THE RESISTANCE BELOW 100.0 OHMS?

NO

REPLACE THE A/C CLUTCH RELAY.*

YES

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE GREY CONNECTOR.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE A/C CLUTCH CONTROL CKT AT PCM TO GROUND. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE A/C CLUTCH RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE THE A/C CLUTCH RELAY CONTROL CIRCUIT...

FROM THE RELAY TO THE PCM. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR OPEN A/C CLUTCH RELAY CONTROL CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
139

T TEST TC-17A REPAIRING - EGR SOLENOID CIRCUIT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

5.9L HD

FIG. 1
5.9L DIESEL

FIG. 2
140

TEST TC-17A REPAIRING - EGR SOLENOID CIRCUIT
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-17A

WITH THE DRB, ERASE TROUBLE CODES.

WITH THE DRB, ACTUATE THE EGR SOLENOID.

WITH THE DRB, READ ALL TROUBLE CODES.

DID THE EGR SOLENOID CONTROL CIRCUIT CODE RETURN?

YES

CONTINUE TEST TC-17A ON THE NEXT PAGE.

NO

NOTE: ACTUATOR TEST MUST STILL BE RUNNING.

WIGGLE WIRING HARNESS FROM THE SOLENOID TO PCM.

DOES THE EGR SOLENOID CONTROL CIRCUIT CODE RETURN?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED THE PROBLEM TO APPEAR.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1 OR 2

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO GENERAL INFO 3.3.2 FOR INFORMATION ON INACTIVE TROUBLE CODES.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
141

T TEST TC-17A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - EGR SOLENOID CIRCUIT

FIG. 1

FIG. 2
142

TEST TC-17A CONTINUED - REPAIRING - EGR SOLENOID CIRCUIT

TEST TC-17A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE EGR SOLENOID CONNECTOR.** SEE GENERAL INFO 4.0

T R O U B L E C O D E

KEY ON, USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE FUSED IGNITION SWITCH OUTPUT CKT. AT THE SOLENOID CONNECTOR. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.*

YES

T E S T S

KEY OFF, DISCONNECT THE PCM CONNECTORS.** USING AN OHMMETER...

MEASURE THE RESISTANCE OF THE CONTROL CKT FROM PCM TO EGR SOLENOID. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN EGR SOLENOID CONTROL CIRCUIT.*

YES

USING AN OHMMETER, MEASURE THE EGR SOLENOID CONTROL CIRCUIT...

FROM THE EGR SOLENOID CONNECTOR TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE EGR SOLENOID CONTROL CIRCUIT SHORT TO GROUND.*

NO

RECONNECT EGR SOLENOID CONNECTOR. KEY ON, USING A VOLTMETER...

MEASURE THE EGR SOLENOID CONTROL CIRCUIT AT THE PCM CONNECTOR. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPLACE THE EGR SOLENOID.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
143

T TEST TC-18A REPAIRING - EVAP PURGE SOLENOID CIRCUIT R O Perform DTC TEST Before Proceeding U AB BODY AN AND XJ BODIES B L E C O D E T E S T S

BR BODY

ZJ BODY

FIG. 1
144

FIG. 2

TEST TC-18A REPAIRING - EVAP PURGE SOLENOID CIRCUIT
Perform DTC TEST Before Proceeding

START TEST TC-18A

RECORD ALL DTC’S AND FREEZE FRAME DATA, NOW ERASE CODES.

T R O U B L E C O D E

WITH THE DRB, MONITOR STATE OF PURGE SOLENOID.

START ENGINE. ALLOW ENGINE TO REACH NORMAL OPERATING TEMPERATURE. (ABOVE 170 DEG.).

T E S T S

DISCONNECT THE PURGE VACUUM HOSE AT THE SOLENOID THAT GOES TO THE CANISTER. SEE GENERAL INFO 4.2

IS PURGE SOLENOID ALLOWING VACUUM THROUGH WHEN THE DRB SHOWS DUTY CYCLE MORE THAN O PERCENT? YES

NO

CONTINUE TEST TC-18A ON THE NEXT PAGE.

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH THE DRB, READ CODES. NOTE: ACTUATOR TEST SHOULD STILL BE RUNNING.

WIGGLE WIRING HARNESS FROM THE SOLENOID TO PCM.

DOES THE EVAP PURGE SOLENOID CONTROL CIRCUIT CODE RETURN?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED PROBLEM TO APPEAR.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
145

T TEST TC-18A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - EVAP PURGE SOLENOID CIRCUIT
AN AND XJ BODIES

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
146

FIG. 4

TEST TC-18A CONTINUED - REPAIRING - EVAP PURGE SOLENOID CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-18A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT EVAP PURGE SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

KEY ON, USING A VOLTMETER, MEASURE THE VOLTAGE OF THE FUSED IGNITION SWITCH OUTPUT...

CIRCUIT AT THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.*

YES

CONTINUE TEST TC-18A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
147

T TEST TC-18A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - EVAP PURGE SOLENOID CIRCUIT
AN AND XJ BODIES

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
148

FIG. 4

TEST TC-18A CONTINUED - REPAIRING - EVAP PURGE SOLENOID CIRCUIT

TEST TC-18A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.2

T R O U B L E C O D E T E S T S

WITH AN OHMMETER, MEASURE THE EVAP PURGE SOLENOID CONTROL CIRCUIT... FIG. 1, 2, 3 OR 4

FROM THE POWERTRAIN CONTROL MODULE TO THE EVAP SOLENOID CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN EVAP PURGE SOLENOID CONTROL CIRCUIT.*

YES

USING AN OHMMETER, MEASURE THE EVAP PURGE SOLENOID CONTROL CIRCUIT TO GROUND...

AT THE PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE EVAP PURGE SOLENOID CONTROL CIRCUIT SHORT TO GROUND.*

NO

RECONNECT EVAP PURGE SOLENOID CONNECTOR. KEY ON, USING A VOLTMETER...

MEASURE THE EVAP PURGE SOLENOID CONTROL CIRCUIT AT THE PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPLACE THE EVAP PURGE SOLENOID.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
149

T TEST TC-19A REPAIRING - INJECTOR #3 CONTROL CIRCUIT R O Perform TEST TC-21A Before Proceeding U AB, AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
150

FIG. 4

TEST TC-19A REPAIRING - INJECTOR #3 CONTROL CIRCUIT
Perform TEST TC-21A Before Proceeding

T R O U B L E C O D E T E S T S
NO REPLACE THE FUEL INJECTOR.*

YES START TEST TC-19A IS THIS A CNG VEHICLE? PERFORM TEST TC-19B.

NO

KEY OFF, DISCONNECT THE INJECTOR #3 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #3. FIG. 1

IS THE RESISTANCE BETWEEN 10.0 AND 16.0 OHMS?

YES

KEY ON, WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2, 3 OR 4

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

TEST TC-19A CONTINUED ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
151

T TEST TC-19A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #3 CONTROL CIRCUIT
AB, AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
152

FIG. 4

TEST TC-19A CONTINUED - REPAIRING - INJECTOR #3 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-19A CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #3 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #3 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

WITH AN OHMMETER, MEASURE ACROSS THE INJECTOR #3 DRIVER CIRCUIT... FIG. 2, 3 OR 4

FROM THE POWERTRAIN CONTROL MODULE CONNECTOR TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #3 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
153

T TEST TC-19B REPAIRING - INJECTOR #3 CONTROL CIRCUIT R O Perform TEST TC-19A Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
154

TEST TC-19B REPAIRING - INJECTOR #3 CONTROL CIRCUIT
Perform TEST TC-19A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-19B

KEY OFF, DISCONNECT THE INJECTOR #3 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #3. FIG. 1

IS THE RESISTANCE BETWEEN 3.0 AND 6.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

KEY ON, WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

TEST TC-19B CONTINUED ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
155

T TEST TC-19B R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #3 CONTROL CIRCUIT

FIG. 1

FIG. 2
156

TEST TC-19B CONTINUED - REPAIRING - INJECTOR #3 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-19B CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #3 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #3 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

WITH AN OHMMETER, MEASURE THE INJECTOR #3 DRIVER CIRCUIT... FIG. 2

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #3 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
157

T TEST TC-20A REPAIRING - INJECTOR #2 CONTROL CIRCUIT R O Perform TEST TC-21A Before Proceeding U AB, AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
158

FIG. 4

TEST TC-20A REPAIRING - INJECTOR #2 CONTROL CIRCUIT
Perform TEST TC-21A Before Proceeding

T R O U B L E C O D E T E S T S
NO REPLACE THE FUEL INJECTOR.*

YES START TEST TC-20A IS THIS A CNG VEHICLE? PERFORM TEST TC-20B.

NO

KEY OFF, DISCONNECT THE INJECTOR #2 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #2. FIG. 1

IS THE RESISTANCE BETWEEN 10.0 AND 16.0 OHMS?

YES

KEY ON, WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2, 3 OR 4

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

TEST TC-20A CONTINUED ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
159

T TEST TC-20A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #2 CONTROL CIRCUIT
AB, AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
160

FIG. 4

TEST TC-20A CONTINUED - REPAIRING - INJECTOR #2 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-20A CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #2 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #2 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

WITH AN OHMMETER, MEASURE ACROSS THE INJECTOR #2 DRIVER CIRCUIT... FIG. 2, 3 OR 4

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #2 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
161

T TEST TC-20B REPAIRING - INJECTOR #2 CONTROL CIRCUIT R O Perform TEST TC-20A Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
162

TEST TC-20B REPAIRING - INJECTOR #2 CONTROL CIRCUIT
Perform TEST TC-20A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-20B

KEY OFF, DISCONNECT THE INJECTOR #2 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #2. FIG. 1

IS THE RESISTANCE BETWEEN 3.0 AND 6.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

KEY ON, WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

TEST TC-20B CONTINUED ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
163

T TEST TC-20B R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #2 CONTROL CIRCUIT

FIG. 1

FIG. 2
164

TEST TC-20B CONTINUED - REPAIRING - INJECTOR #2 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-20B CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #2 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #2 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

WITH AN OHMMETER, MEASURE ACROSS THE INJECTOR #2 DRIVER CIRCUIT... FIG. 2

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #2 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
165

T TEST TC-21A REPAIRING - INJECTOR CONTROL CIRCUITS R O Perform DTC TEST Before Proceeding U ALL 4-CYLINDER ENGINES ALL 6-CYLINDER ENGINES B L E C O D E T E S T S

ALL 8-CYLINDER ENGINES

ALL 10-CYLINDER ENGINES

FIG. 1
166

FIG. 2

TEST TC-21A REPAIRING - INJECTOR CONTROL CIRCUITS
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-21A

START ENGINE, LET IDLE FOR AT LEAST 20 SECONDS.

KEY ON, ENGINE OFF.

WITH THE DRB, READ TROUBLE CODES.

DOES THE DRB SHOW ANY "INJECTOR CONTROL CIRCUIT" CODE WITH A START RUN COUNT OF ZERO? NO

YES

CONTINUE TEST TC-21A ON THE NEXT PAGE.

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

START ENGINE.

WIGGLE WIRING HARNESS FROM THE INJECTOR TO THE PCM.

DOES THE ENGINE MISS OR STALL?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED PROBLEM TO APPEAR.*

NO

REFER TO FIGURE 2 FOR ADDTIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
167

T TEST TC-21A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR CONTROL CIRCUITS

NOTES

168

TEST TC-21A CONTINUED − REPAIRING − INJECTOR CONTROL CIRCUITS
Refer to the chart below and perform the diagnostic test that corresponds to the trouble code displayed on the DRB.

T R O U B L E C O D E T E S T S

TROUBLE CODE INJECTOR #1 CONTROL CIRCUIT INJECTOR #2 CONTROL CIRCUIT INJECTOR #3 CONTROL CIRCUIT INJECTOR #4 CONTROL CIRCUIT INJECTOR #5 CONTROL CIRCUIT INJECTOR #6 CONTROL CIRCUIT INJECTOR #7 CONTROL CIRCUIT INJECTOR #8 CONTROL CIRCUIT INJECTOR #9 CONTROL CIRCUIT INJECTOR #10 CONTROL CIRCUIT

DIAGNOSTIC TEST TC-21B TC-20A TC-19A TC-61A TC-69A TC-70A TC-79A TC-80A TC-55A TC-56A

169

T TEST TC-21B REPAIRING - INJECTOR #1 CONTROL CIRCUIT R O Perform TEST TC-21A Before Proceeding U AB, AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
170

FIG. 4

TEST TC-21B REPAIRING - INJECTOR #1 CONTROL CIRCUIT
Perform TEST TC-21A Before Proceeding

T R O U B L E C O D E T E S T S
NO REPLACE THE FUEL INJECTOR.*

YES START TEST TC-21B IS THIS A CNG VEHICLE? PERFORM TEST TC-21C

NO

KEY OFF, DISCONNECT THE INJECTOR #1 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #1. FIG. 1

IS THE RESISTANCE BETWEEN 10.0 AND 16.0 OHMS?

YES

KEY ON, WITH THE DRB, ACTUATE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2, 3 OR 4

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

CONTINUE TEST TC-21B ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
171

T TEST TC-21B R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #1 CONTROL CIRCUIT
AB, AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
172

FIG. 4

TEST TC-21B CONTINUED - REPAIRING - INJECTOR #1 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-21B CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #1 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #1 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #1 DRIVER CIRCUIT... FIG. 2, 3 OR 4

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #1 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
173

T TEST TC-21C REPAIRING - INJECTOR #1 CONTROL CIRCUIT R O Perform TEST TC-21B Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
174

TEST TC-21C REPAIRING - INJECTOR #1 CONTROL CIRCUIT
Perform TEST TC-21B Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-21C

KEY OFF, DISCONNECT THE INJECTOR #1 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #1. FIG. 1

IS THE RESISTANCE BETWEEN 3.0 AND 6.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

KEY ON, WITH THE DRB, ACTUATE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

CONTINUE TEST TC-21C ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
175

T TEST TC-21C R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #1 CONTROL CIRCUIT

FIG. 1

FIG. 2
176

TEST TC-21C CONTINUED - REPAIRING - INJECTOR #1 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-21C CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #1 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #1 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #1 DRIVER CIRCUIT... FIG. 2

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #1 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
177

T TEST TC-25A REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1
AB, AN, BR AND XJ BODIES ZJ BODY

178

TEST TC-25A REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS
Perform DTC TEST Before Proceeding

START TEST TC-25A

TURN IGNITION OFF FOR 10 SECONDS.

START ENGINE, ALLOW TO IDLE FOR 20 SECONDS.

T R O U B L E C O D E

NOTE: IF THE ENGINE WILL NOT IDLE, HOLD THE THROTTLE OPEN SLIGHTLY TO KEEP ENGINE RUNNING.

WITH THE DRB ACTUATE THE IDLE AIR CONTROL MOTOR TO 1400 RPM.

NOTE: RELEASE THROTTLE. IS THE ENGINE SPEED 1400 +/- 100 RPM? YES

NO

CONTINUE TEST TC-25A ON THE NEXT PAGE.

T E S T S

WITH THE DRB ACTUATE THE IDLE AIR CONTROL MOTOR TO 900 RPM.

IS THE ENGINE SPEED 900 +/- 100 RPM?

NO

CONTINUE TEST TC-25A ON THE NEXT PAGE.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

START ENGINE. WITH THE DRB IN SYSTEMS TESTS, PERFORM THE IAC WIGGLE TEST.

THE IDLE SPEED SHOULD RAISE AND LOWER WITH THE DISPLAY.

DOES THE IDLE SPEED RAISE AND LOWER PROPERLY?

NO

CONTINUE TEST TC-25A ON THE NEXT PAGE.

YES

WIGGLE THE WIRING HARNESS FROM THE IAC MOTOR TO THE PCM.

OBSERVE FOR THE IAC MOTOR TO STOP OPERATING.

DID THE IAC STOP OPERATING AT ANY TIME?

YES

REPAIR THE HARNESS OR CONNECTORS AS NECESSARY.*

NO

WITH THE DRB, STOP THE IAC WIGGLE TEST.

REFER TO GENERAL INFO 3.3.2 FOR INFORMATION ON INACTIVE TROUBLE CODES.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
179

T TEST TC-25A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS
AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
180

FIG. 4

TEST TC-25A CONTINUED - REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS

TEST TC-25A CONTINUED FROM THE PREVIOUS PAGE.

USING THE DRB, STOP ALL TESTS.

T R O U B L E C O D E

WITH THE ENGINE STILL RUNNING, DISCONNECT THE IAC MOTOR CONNECTOR.**

T E S T S
WAS THE VOLTAGE OVER 5.0 VOLTS AT ANY TIME? NO PERFORM TEST TC-25B

USING A VOLTMETER, MEASURE THE IAC DRIVER #1 CIRCUIT. FIG. 1, 2, 3 OR 4

YES

USING A VOLTMETER, MEASURE THE IAC DRIVER #2 CIRCUIT. FIG. 1, 2, 3 OR 4

WAS THE VOLTAGE OVER 5.0 VOLTS AT ANY TIME?

NO

PERFORM TEST TC-25C

YES

USING A VOLTMETER, MEASURE THE IAC DRIVER #3 CIRCUIT. FIG. 1, 2, 3 OR 4

WAS THE VOLTAGE OVER 5.0 VOLTS AT ANY TIME?

NO

PERFORM TEST TC-25D

YES

USING A VOLTMETER, MEASURE THE IAC DRIVER #4 CIRCUIT. FIG. 1, 2, 3 OR 4

WAS THE VOLTAGE OVER 5.0 VOLTS AT ANY TIME?

NO

PERFORM TEST TC-25E

YES

CONTINUE TEST TC-25A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
181

T TEST TC-25A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS
AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
182

FIG. 4

TEST TC-25A CONTINUED - REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS

TEST TC-25A CONTINUED FROM THE PREVIOUS PAGE.

TURN KEY OFF.

T R O U B L E C O D E

USING AN OHMMETER, MEASURE BETWEEN...

THE IAC DRIVER #1 AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IAC #1 DRIVER CIRCUIT SHORTED TO GROUND.*

NO

T E S T S

USING AN OHMMETER, MEASURE BETWEEN...

THE IAC DRIVER #2 AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IAC #2 DRIVER CIRCUIT SHORTED TO GROUND.*

NO

USING AN OHMMETER, MEASURE BETWEEN...

THE IAC DRIVER #3 AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IAC #3 DRIVER CIRCUIT SHORTED TO GROUND.*

NO

USING AN OHMMETER, MEASURE BETWEEN...

THE IAC DRIVER #4 AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IAC #4 DRIVER CIRCUIT SHORTED TO GROUND.*

NO

CONTINUE TEST TC-25A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
183

T TEST TC-25A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS
AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
184

FIG. 4

TEST TC-25A CONTINUED - REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS

TEST TC-25A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

T R O U B L E C O D E T E S T S

NO

THE FOLLOWING STEPS ARE CHECKING FOR A SHORT BETWEEN THE DRIVER CIRCUITS...

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE...

IAC #1 DRIVER AND #2, #3, #4 DRIVERS. FIG. 1, 2 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS ON ANY OF THE DRIVERS?

YES

REPAIR THE IAC DRIVER CIRCUITS, SHORTED TOGETHER.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE...

IAC #2 DRIVER AND #3,#4 DRIVERS. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS ON ANY OF THE DRIVERS?

YES

REPAIR THE IAC DRIVER CIRCUITS, SHORTED TOGETHER.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE...

IAC #3 DRIVER AND #4 DRIVER. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IAC DRIVER CIRCUITS, SHORTED TOGETHER.*

NO

REPLACE THE IDLE AIR CONTROL MOTOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
185

T TEST TC-25B REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS R O Perform TEST TC-25A Before Proceeding U AB BODY AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
186

FIG. 4

TEST TC-25B REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS
Perform TEST TC-25A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-25B.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL INFO 4.0

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE IAC #1 DRIVER CKT... FIG. 1, 2, 3 OR 4

FROM THE POWERTRAIN CONTROL MODULE CONNECTOR TO THE IAC CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN IDLE AIR CONTROL MOTOR DRIVER CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
187

T TEST TC-25C REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS R O Perform TEST TC-25A Before Proceeding U AB BODY AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
188

FIG. 4

TEST TC-25C REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS
Perform TEST TC-25A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-25C.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL INFO 4.1

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE IAC #2 DRIVER CKT... FIG. 1, 2, 3 OR 4

FROM THE POWERTRAIN CONTROL MODULE CONNECTOR TO THE IAC CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN IDLE AIR CONTROL MOTOR DRIVER CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
189

T TEST TC-25D REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS R O Perform TEST TC-25A Before Proceeding U AB BODY AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
190

FIG. 4

TEST TC-25D REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS
Perform TEST TC-25A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-25D.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL INFO 4.1

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE IAC #3 DRIVER CKT... FIG. 1, 2, 3 OR 4

FROM THE POWERTRAIN CONTROL MODULE CONNECTOR TO THE IAC CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN IDLE AIR CONTROL MOTOR DRIVER CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
191

T TEST TC-25E REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS R O Perform TEST TC-25A Before Proceeding U AB BODY AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
192

FIG. 4

TEST TC-25E REPAIRING - IDLE AIR CONTROL MOTOR CIRCUITS
Perform TEST TC-25A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-25E.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL INFO 4.1

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE IAC #4 DRIVER CKT... FIG. 1, 2, 3 OR 4

FROM THE POWERTRAIN CONTROL MODULE CONNECTOR TO THE IAC CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN IDLE AIR CONTROL MOTOR DRIVER CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
193

T TEST TC-26A REPAIRING - THROTTLE POSITION SENSOR VOLTAGE LOW R O Perform DTC TEST Before Proceeding U ZJ BODY ALL OTHERS B L E C O D E T E S T S

FIG. 1
194

FIG. 2

TEST TC-26A REPAIRING - THROTTLE POSITION SENSOR VOLTAGE LOW
Perform DTC TEST Before Proceeding

START TEST TC-26A.

WITH THE DRB, READ THE THROTTLE POSITION SENSOR (TP SENSOR) VOLTAGE.

IS THE THROTTLE POSITION SENSOR VOLTAGE BELOW 0.2 VOLT?

T R O U B L E
CONTINUE TEST TC-26A ON THE NEXT PAGE.

YES

NO

C O D E T E S T S

WHILE MONITORING THE DRB, SLOWLY OPEN AND CLOSE THE THROTTLE.

IS THE VOLTAGE CHANGE SMOOTH?

NO

REPLACE THE THROTTLE POSITION SENSOR.*

YES

STOP MOVING LINKAGE. WIGGLE THROTTLE POSITION SENSOR CONNECTORS AND HARNESS.

MONITOR THE DRB DISPLAY.

WAS THERE ANY CHANGE IN THROTTLE POSITION SENSOR VOLTAGE WHEN WIGGLED? NO

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

THE PROBLEM DOES NOT EXSIST AT THIS TIME. FIG. 2

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
195

T TEST TC-26A CONTINUED - REPAIRING - THROTTLE POSITION SENSOR VOLTAGE LOW R O U AB, AN, BR AND XJ BODIES B L E C O D E T E S T S
FIG. 1
BR DIESEL

FIG. 2
ZJ BODY

FIG. 3
196

TEST TC-26A CONTINUED - REPAIRING - THROTTLE POSITION SENSOR VOLTAGE LOW

TEST TC-26A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE THROTTLE POSITION (TP) SENSOR.** SEE GENERAL INFO 4.4

T R O U B L E C O D E

USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE THROTTLE POSITION SENSOR 5-VOLT SUPPLY CIRCUIT. FIG. 1, 2 OR 3

IS THE VOLTAGE BELOW 4.0 VOLTS?

YES

REPAIR THE OPEN TP SENSOR 5-VOLT SUPPLY CIRCUIT.*

NO

T E S T S

WITH THE DRB, READ THE THROTTLE POSITION SENSOR VOLTAGE.

IS THE VOLTAGE ABOVE 1.0 VOLT?

YES

REPLACE THE THROTTLE POSITION SENSOR.*

NO

IS THIS A XJ WITH A 4.OL ENGINE AND A AW4 TRANS?

YES

CONTINUE TEST TC-26A ON THE PAGE.

NO

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

USING AN OHMMETER, MEASURE THE TP SENSOR SIGNAL CIRCUIT TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE THROTTLE POSITION SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE BETWEEN THE SENSOR SIGNAL CKT AND THE SENSOR GROUND CKT. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE SENSOR SIGNAL CIRCUIT SHORTED TO SENSOR GROUND CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
197

T TEST TC-26A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - THROTTLE POSITION SENSOR VOLTAGE LOW

FIG. 1

198

TEST TC-26A CONTINUED - REPAIRING - THROTTLE POSITION SENSOR VOLTAGE LOW

TEST TC-26A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF. DISCONNECT THE TRANSMISSION CONTROL MODULE.**

T R O U B L E C O D E T E S T S

KEY ON. WITH THE DRB, READ THE THROTTLE POSITION SENSOR VOLTAGE.

IS THE VOLTAGE ABOVE 1.0 VOLT?

YES

REPLACE THE TRANSMISSION CONTROL MODULE.*

NO

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE TP SENSOR SIGNAL CIRCUIT TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE THROTTLE POSITION SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE BETWEEN THE SENSOR SIGNAL CIRCUIT AND THE SENSOR GROUND CKT. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE SENSOR SIGNAL CIRCUIT SHORTED TO SENSOR GROUND CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
199

T TEST TC-27A REPAIRING - THROTTLE POSITION SENSOR VOLTAGE HIGH R O Perform DTC TEST Before Proceeding U ZJ BODY ALL OTHERS B L E C O D E T E S T S

FIG. 1
200

FIG. 2

TEST TC-27A REPAIRING - THROTTLE POSITION SENSOR VOLTAGE HIGH
Perform DTC TEST Before Proceeding

START TEST TC-27A.

WITH THE DRB, READ THE THROTTLE POSITION SENSOR VOLTAGE.

IS THE THROTTLE POSITION SENSOR VOLTAGE ABOVE 4.5 VOLTS?

T R O U B L E
CONTINUE TEST TC-27A ON THE NEXT PAGE.

YES

NO

C O D E T E S T S

WHILE MONITORING THE DRB, SLOWLY OPEN AND CLOSE THE THROTTLE.

IS THE VOLTAGE CHANGE SMOOTH?

NO

REPLACE THE THROTTLE POSITION SENSOR.*

YES

WIGGLE THROTTLE POSITON SENSOR CONNECTORS AND HARNESS.

MONITOR THE DRB DISPLAY.

WAS THERE ANY CHANGE IN THROTTLE POSITION SENSOR VOLTAGE WHEN WIGGLED? NO

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

THE PROBLEM DOES NOT EXSIST AT THIS TIME. FIG. 2

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
201

T TEST TC-27A CONTINUED - REPAIRING - THROTTLE POSITION SENSOR VOLTAGE HIGH R O U AB, AN, BR AND XJ BODIES B L E C O D E T E S T S
FIG. 1
BR DIESEL

FIG. 2
ZJ BODY

FIG. 3
202

TEST TC-27A CONTINUED - REPAIRING - THROTTLE POSITION SENSOR VOLTAGE HIGH

TEST TC-27A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE THROTTLE POSITION SENSOR.** SEE GENERAL INFO 4.0

T R O U B L E C O D E T E S T S

CONNECT A JUMPER WIRE BETWEEN THE TP SENSOR SIGNAL CKT AND SENSOR GND CKT.FIG. 1, 2 OR 3

USING THE DRB, READ THE THROTTLE POSITION SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 1.0 VOLT?

YES

REPLACE THE THROTTLE POSITION SENSOR.*

NO

DOES THE DRB SHOW NO RESPONSE?

YES

REPAIR THE 5-VOLT SUPPLY SHORTED TO TP SENSOR SIGNAL CIRCUIT.*

NO

MOVE THE JUMPER WIRE BETWEEN THE SENSOR SIGNAL CIRCUIT AND A GOOD ENGINE GROUND. FIG. 1, 2 OR 3

READ THE THROTTLE POSITION SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 1.0 VOLT?

YES

REPAIR THE OPEN TP SENSOR GROUND CIRCUIT.*

CONTINUE TEST TC-27A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
203

T TEST TC-27A CONTINUED - REPAIRING - THROTTLE POSITION SENSOR VOLTAGE HIGH R O U AB, AN, BR AND XJ BODIES B L E C O D E T E S T S
FIG. 1
BR DIESEL

FIG. 2
ZJ BODY

FIG. 3
204

TEST TC-27A CONTINUED - REPAIRING - THROTTLE POSITION SENSOR VOLTAGE HIGH

T R O U B L E C O D E T E S T S

TEST TC-27A CONTINUED FROM THE PREVIOUS PAGE.

TURN IGNITION OFF.

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE THROTTLE POSITION SENSOR SIGNAL CIRCUIT FOR RESISTANCE. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN TP SENSOR SIGNAL CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
205

T TEST TC-30A REPAIRING - ECT SENSOR VOLTAGE TOO LOW R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
206

TEST TC-30A REPAIRING - ECT SENSOR VOLTAGE TOO LOW
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-30A.

WITH THE DRB, READ THE ENGINE COOLANT TEMPERATURE SENSOR (ECT) VOLTAGE.

IS THE ENGINE COOLANT TEMPERATURE SENSOR VOLTAGE BELOW 0.5 VOLT? NO

YES

CONTINUE TEST TC-30A ON THE NEXT PAGE.

WIGGLE THE ENGINE COOLANT TEMPERATURE SENSOR CONNECTOR & HARNESS.

MONITOR THE DRB DISPLAY.

WAS THERE ANY ENGINE COOLANT TEMPERATURE SENSOR VOLTAGE CHANGE?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
207

T TEST TC-30A CONTINUED - REPAIRING - ECT SENSOR VOLTAGE TOO LOW R O U AB, AN, BR AND ZJ 5.2L B L E C O D E T E S T S
FIG. 1
XJ BODY

FIG. 2
ZJ 4.0L

FIG. 3
208

TEST TC-30A CONTINUED - REPAIRING - ECT SENSOR VOLTAGE TOO LOW

T R O U B L E C O D E T E S T S

TEST TC-30A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE ENGINE COOLANT TEMPERATURE (ECT) SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

WITH THE DRB, READ THE ECT SENSOR VOLTAGE.

IS THE ECT SENSOR VOLTAGE ABOVE 4.0 VOLTS?

YES

REPLACE THE ECT SENSOR.*

NO

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE ECT SENSOR SIGNAL CIRCUIT TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

WITH AN OHMMETER, MEASURE BETWEEN THE...

ECT SENSOR SIGNAL CIRCUIT AND THE SENSOR GROUND CIRCUIT. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE ECT SENSOR SIGNAL CIRCUIT SHORTED TO THE SENSOR GROUND CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
209

T TEST TC-31A REPAIRING - ECT SENSOR VOLTAGE TOO HIGH R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
210

TEST TC-31A REPAIRING - ECT SENSOR VOLTAGE TOO HIGH
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-31A.

WITH THE DRB, READ THE ENGINE COOLANT TEMPERATURE (ECT) SENSOR VOLTAGE.

IS THE ENGINE COOLANT TEMPERATURE SENSOR VOLTAGE ABOVE 4.5 VOLTS? NO

YES

CONTINUE TEST TC-31A ON THE NEXT PAGE.

WIGGLE THE ENGINE COOLANT TEMP SENSOR CONNECTOR & HARNESS.

MONITOR THE DRB DISPLAY.

WAS THERE ANY ENGINE COOLANT TEMPERATURE SENSOR VOLTAGE CHANGE?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
211

T TEST TC-31A CONTINUED - REPAIRING - ECT SENSOR VOLTAGE TOO HIGH R O U AB, AN, BR AND ZJ 5.2L XJ BODY B L E C O D E T E S T S
FIG. 1
ZJ 4.0L

FIG. 2
AB, AN, BR AND ZJ 5.2L

FIG. 3
XJ BODY ZJ 4.0L

FIG. 4

FIG. 5
212

FIG. 6

TEST TC-31A CONTINUED - REPAIRING - ECT SENSOR VOLTAGE TOO HIGH

TEST TC-31A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE ENGINE COOLANT TEMPERATURE (ECT) SENSOR.** SEE GENERAL INFO 4.4

T R O U B L E C O D E

WITH A VOLTMETER, MEASURE THE ECT SENSOR SIGNAL... FIG. 1, 2 OR 3

AT THE ECT SENSOR CONNECTOR.

IS THE VOLTAGE ABOVE 4.5 VOLTS?

YES

REPAIR THE ECT SENSOR SIGNAL SHORTED TO VOLTAGE.*

NO

T E S T S

CONNECT A JUMPER BETWEEN THE ECT SENSOR SIGNAL AND SENSOR GROUND CKT. FIG. 1, 2 OR 3

WITH THE DRB, READ THE ECT SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 1.0 VOLT?

YES

REPLACE THE ECT SENSOR.*

NO

MOVE THE JUMPER WIRE FROM THE SENSOR GROUND TO AN ENGINE GROUND. FIG. 1, 2 OR 3

WITH THE DRB, READ THE ENGINE COOLANT TEMPERATURE SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 1.0 VOLT?

YES

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

NO

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE ECT SENSOR SIGNAL CIRCUIT FOR RESISTANCE... FIG. 4, 5 OR 6

FROM THE PCM TO THE ECT SENSOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN ECT SENSOR SIGNAL CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
213

T TEST TC-35A REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
214

TEST TC-35A REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S
NO CONTINUE TEST TC-35A ON THE NEXT PAGE.

START TEST TC-35A.

RAISE THE DRIVE WHEELS OFF THE GROUND.

WARNING: BE SURE TO KEEP HANDS AND FEET CLEAR OF ROTATING WHEELS.

START ENGINE, WITH THE DRB, READ THE VEHICLE SPEED SENSOR.

PUT THE TRANSMISSION IN ANY FORWARD GEAR.

DOES THE DRB SHOW ABOVE ZERO MPH?

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY. *

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
215

T TEST TC-35A R O U XJ BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL

FIG. 1
ALL OTHER BODIES

FIG. 2
216

TEST TC-35A CONTINUED - REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL

TEST TC-35A CONTINUED FROM PREVIOUS PAGE.

WITH THE WHEELS STILL ROLLING, OBSERVE THE SPEEDOMETER.

DOES THE SPEEDOMETER DISPLAY SHOW ABOVE ZERO MPH?

YES

PERFORM TEST TC-35C

T R O U B L E C O D E

NO

HOIST VEHICLE, CHECK THE VSS ADAPTER FOR PROPER SEATING AND POSITIONING. SEE SERVICE MANUAL.

WAS THE ADAPTER POSITIONED AND SEATED PROPERLY?

NO

REPAIR AS NECESSARY.*

YES

T E S T S

KEY OFF, DISCONNECT THE VEHICLE SPEED SENSOR(VSS) CONNECTOR.** SEE GENERAL INFO 4.4

KEY ON, MEASURE THE VOLTAGE AT THE 5-VOLT SUPPLY CIRCUIT. FIG. 1 OR 2

IS THE VOLTAGE ABOVE 4.0 VOLTS?

NO

REPAIR THE OPEN 5-VOLT SUPPLY CIRCUIT.*

YES

KEY OFF. DISCONNECT THE INSTRUMENT CLUSTER CONNECTOR.**

KEY ON. MEASURE THE VOLTAGE AT THE VEHICLE SPEED SENSOR SIGNAL CIRCUIT. FIG. 1 OR 2

IS THE VOLTAGE ABOVE 4.5 VOLTS?

NO

CONTINUE TEST TC-35A ON THE NEXT PAGE.

YES

CONNECT ONE END OF A JUMPER WIRE TO THE VSS SENSOR SIGNAL CIRCUIT. FIG. 1 OR 2

WITH THE DRB, READ THE VSS SIGNAL.

WHILE OBSERVING DISPLAY, TAP THE OTHER END OF JUMPER TO THE SENSOR GROUND CIRCUIT.

DOES THE DISPLAY SHOW MORE THAN 0 MPH?

NO

PERFORM TEST TC-35B.

YES

REMOVE THE VEHICLE SPEED SENSOR. INSPECT THE SPEEDOMETER PINION GEAR.

IS THE PINION GEAR OK?

NO

REPAIR AS NECESSARY.*

YES

REPLACE THE VEHICLE SPEED SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
217

T TEST TC-35A R O U AN BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL
ALL OTHER BODIES

FIG. 1
AN BODY ALL OTHER BODIES

FIG. 2

FIG. 3
218

FIG. 4

TEST TC-35A CONTINUED - REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL

T R O U B L E C O D E T E S T S

TEST TC-35A CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

MEASURE THE RESISTANCE OF THE VEHICLE SPEED SENSOR SIGNAL CIRCUIT...

FROM THE PCM CONNECTOR TO THE VSS CONNECTOR. FIG. 1 OR 2

NO IS THE RESISTANCE BELOW 5.0 OHMS? REPAIR THE OPEN SPEED SENSOR SIGNAL CIRCUIT.*

YES

MEASURE THE RESISTANCE BETWEEN THE VSS SIGNAL CIRCUIT AND GROUND. FIG. 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

CONTINUE TEST TC-35A ON THE NEXT PAGE.

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
219

T TEST TC-35A R O U AN BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL

FIG. 1
ALL OTHER BODIES

FIG. 2
220

TEST TC-35A CONTINUED - REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL

T R O U B L E C O D E T E S T S

TEST TC-35A CONTINUED FROM PREVIOUS PAGE.

IS THE VEHICLE EQUIPPED WITH DAYLIGHT RUNNING LAMPS?

NO

REPAIR THE VEHICLE SPEED SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

YES

DISCONNECT THE DAYLIGHT RUNNING LAMP MODULE.**

MEASURE THE RESISTANCE BETWEEN THE VSS SIGNAL CIRCUIT AND GROUND FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE VSS SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

REPLACE THE DAYLIGHT RUNNING LAMP MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
221

T TEST TC-35B REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL R O Perform TEST TC-35A Before Proceeding U AN BODY B L E C O D E T E S T S

FIG. 3
ALL OTHER BODIES

FIG. 2
222

TEST TC-35B REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL
Perform TEST TC-35A Before Proceeding

T R O U B L E C O D E

START TEST TC-35B.

CONNECT ONE END OF A JUMPER WIRE TO THE VSS SENSOR SIGNAL CIRCUIT. FIG. 1 OR 2

WITH THE DRB, READ THE VSS SIGNAL.

T E S T S

WHILE OBSERVING DISPLAY, TAP OTHER END OF JUMPER TO GROUND. FIG. 1 OR 2

DOES THE DISPLAY SHOW MORE THAN 0 MPH?

YES

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
223

T TEST TC-35C REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL R O Perform TEST TC-35A Before Proceeding U AN BODY B L E C O D E T E S T S

FIG. 1
ALL OTHER BODIES

FIG. 2
224

TEST TC-35C REPAIRING - NO VEHICLE SPEED SENSOR SIGNAL
Perform TEST TC-35A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST 35C.

KEY OFF. DISCONNECT THE WHITE PCM CONNECTOR.**

MEASURE THE VOLTAGE AT THE VSS SIGNAL CIRCUIT. FIG. 1 OR 2

IS THE VOLTAGE ABOVE 4.5 VOLTS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN VSS SIGNAL CIRCUIT BETWEEN THE VSS AND THE PCM.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
225

T TEST TC-36A REPAIRING - MAP SENSOR VOLTAGE TOO LOW - NO 5 VOLTS TO MAP SENSOR R O Perform DTC TEST Before Proceeding U ZJ BODY ALL OTHERS B L E C O D E T E S T S

FIG. 1

FIG. 2

FIG. 3
226

TEST TC-36A REPAIRING - MAP SENSOR VOLTAGE TOO LOW - NO 5 VOLTS TO MAP SENSOR
Perform DTC TEST Before Proceeding

START TEST TC-36A.

START ENGINE AND LET IDLE.

T R O U B L E C O D E

WITH THE DRB, READ THE MAP SENSOR VOLTAGE.

IS THE MAP SENSOR VOLTAGE BELOW 1.2 VOLTS?

YES

CONTINUE TEST TC-36A ON THE NEXT PAGE.

NO

T E S T S

TURN IGNITION ON. (ENGINE OFF)

WITH THE DRB, READ THE MAP SENSOR VOLTAGE.

IS THE MAP SENSOR VOLTAGE BELOW 2.35 VOLTS?

YES

CONTINUE TEST TC-36A ON THE NEXT PAGE.

NO

WIGGLE THE MAP SENSOR CONNECTOR & HARNESS. SEE GENERAL INFO 4.4

MONITOR THE DRB DISPLAY.

WAS THERE ANY MAP SENSOR VOLTAGE CHANGE?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE TO CHANGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1 OR 2

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 3 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
227

T TEST TC-36A CONTINUED - REPAIRING - MAP SENSOR VOLTAGE TOO LOW - NO 5 VOLTS TO MAP SENSOR R O U AB, AN, BR AND XJ BODIES B L E C O D E T E S T S
FIG. 1
BR 8.0L

FIG. 2
ZJ BODY

FIG. 3
228

- REPAIRING - MAP SENSOR VOLTAGE TOO LOW - NO 5 VOLTS TO TEST TC-36A CONTINUED MAP SENSOR

TEST TC-36A CONTINUED FROM THE PREVIOUS PAGE.

TURN ENGINE OFF AND IGNITION ON (IF ENGINE IS RUNNING).

DISCONNECT THE MAP SENSOR ELECTRICAL CONNECTOR.** SEE GENERAL INFO 4.4

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE VOLTAGE OF THE MAP SENSOR 5-VOLT SUPPLY CIRCUIT AT THE...

MAP SENSOR CONNECTOR. FIG. 1, 2 OR 3

IS THE VOLTAGE ABOVE 4.5 VOLTS?

NO

CONTINUE TEST TC-36A ON THE NEXT PAGE.

YES

T E S T S

USE THE DRB TO READ MAP SENSOR VOLTAGE.

IS THE MAP SENSOR VOLTAGE ABOVE 4.5 VOLTS?

YES

REPLACE THE MAP SENSOR.*

NO

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE RESISTANCE BETWEEN THE MAP SENSOR SIGNAL CIRCUIT AND...

THE MAP SENSOR GROUND CIRCUIT AT MAP SENSOR CONNECTOR. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR MAP SENSOR SIGNAL CIRCUIT SHORTED TO MAP SENSOR GROUND CIRCUIT.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE MAP SENSOR SIGNAL CIRCUIT...

AT MAP SENSOR CONNECTOR TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE MAP SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
229

T TEST TC-36A CONTINUED - REPAIRING - MAP SENSOR VOLTAGE TOO LOW - NO 5 VOLTS TO MAP SENSOR R O U AB, AN, BR AND XJ BODIES B L E C O D E T E S T S
FIG. 1
BR 8.0L

FIG. 2
ZJ BODY

FIG. 3
230

- REPAIRING - MAP SENSOR VOLTAGE TOO LOW - NO 5 VOLTS TO TEST TC-36A CONTINUED MAP SENSOR

TEST TC-36A CONTINUED FROM THE PREVIOUS PAGE.

T R O U B L E C O D E T E S T S

TURN IGNITION OFF.

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE RESISTANCE OF THE MAP SENSOR 5-VOLT SUPPLY CIRCUIT...

FROM THE MAP SENSOR CONNECTOR TO THE PCM CONNECTOR. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN 5-VOLT SUPPLY CIRCUIT.*

YES

WITH AN OHMMETER.

MEASURE THE MAP SENSOR 5-VOLT SUPPLY CKT FOR RESISTANCE TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE 5-VOLT SUPPLY CIRCUIT FOR A SHORT TO GROUND.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
231

T TEST TC-37A REPAIRING - MAP SENSOR VOLTAGE TOO HIGH R O Perform DTC TEST Before Proceeding U ZJ BODY ALL OTHERS B L E C O D E T E S T S

FIG. 1
232

FIG. 2

TEST TC-37A REPAIRING - MAP SENSOR VOLTAGE TOO HIGH
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-37A.

START THE ENGINE.

WITH THE DRB, READ THE MAP SENSOR VOLTAGE.

IS THE MAP SENSOR VOLTAGE ABOVE 4.6 VOLTS?

YES

CONTINUE TEST TC-37A ON THE NEXT PAGE.

NO

WIGGLE MAP SENSOR CONNECTOR & HARNESS. SEE GENERAL INFO 4.4

MONITOR THE DRB DISPLAY.

WAS THERE ANY MAP SENSOR VOLTAGE CHANGE WHEN WIGGLED?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE HARNESS AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
233

T TEST TC-37A CONTINUED - REPAIRING - MAP SENSOR VOLTAGE TOO HIGH R O U AB, AN, BR AND XJ BODIES B L E C O D E T E S T S
FIG. 1
BR 8.0L

FIG. 2
ZJ BODY

FIG. 3
234

TEST TC-37A CONTINUED - REPAIRING - MAP SENSOR VOLTAGE TOO HIGH

TEST TC-37A CONTINUED FROM THE PREVIOUS PAGE.

TURN ENGINE OFF (IGNITION ON)

DISCONNECT THE MAP SENSOR ELECTRICAL CONNECTOR.** SEE GENERAL INFO 4.4

T R O U B L E C O D E

USING A VOLTMETER IN THE FOLLOWING STEP, MEASURE THE VOLTAGE OF THE MAP SENSOR SIGNAL...

CIRCUIT AT THE MAP SENSOR CONNECTOR. FIG. 1, 2 OR 3

IS THE VOLTAGE ABOVE 5.5 VOLTS?

YES

REPAIR MAP SENSOR SIGNAL SHORTED TO BATTERY VOLTAGE.

NO

T E S T S

KEY OFF, USING AN OHMMETER, MEASURE THE RESISTANCE OF THE MAP SENSOR SIGNAL...

CIRCUIT TO 5-VOLT SUPPLY CIRCUIT.

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR SHORTED MAP SENSOR SIGNAL CIRCUIT SHORTED TO 5-VOLTS.*

NO

CONNECT A JUMPER WIRE BETWEEN THE SENSOR SIGNAL AND SENSOR GROUND CKTS. FIG. 1, 2 OR 3

READ THE MAP SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 1.0 VOLT?

YES

REPLACE THE MAP SENSOR.*

NO

MOVE THE JUMPER WIRE FROM THE SENSOR GROUND CIRCUIT TO ENGINE GROUND. FIG. 1, 2 OR 3

READ THE MAP SENSOR VOLTAGE.

IS THE MAP SENSOR VOLTAGE BELOW 1.0 VOLT?

YES

REPAIR THE OPEN MAP SENSOR GROUND CIRCUIT.*

CONTINUE TEST TC-37A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
235

T TEST TC-37A CONTINUED - REPAIRING - MAP SENSOR VOLTAGE TOO HIGH R O U AB, AN, BR AND XJ BODIES B L E C O D E T E S T S
FIG. 1
BR 8.0L

FIG. 2
ZJ BODY

FIG. 3
236

TEST TC-37A CONTINUED - REPAIRING - MAP SENSOR VOLTAGE TOO HIGH

T R O U B L E C O D E T E S T S

TEST TC-37A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE MAP SENSOR SIGNAL CIRCUIT BETWEEN THE PCM CONNECTOR...

AND THE MAP SENSOR CONNECTOR. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN MAP SENSOR SIGNAL CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
237

T TEST TC-39A REPAIRING - NO CHANGE IN MAP FROM START TO RUN R O Perform DTC TEST Before Proceeding U ZJ BODY B L E C O D E T E S T S

ALL OTHERS

FIG. 1
238

TEST TC-39A REPAIRING - NO CHANGE IN MAP FROM START TO RUN
Perform DTC TEST Before Proceeding

START TEST TC-39A.

TURN IGNITION ON. (ENGINE OFF)

WITH THE DRB, READ CODES. IS "MAP SENSOR VOLTAGE TOO LOW" CODE SET?

YES

PERFORM TEST TC-36A.

T R O U B L E C O D E

NO

WITH THE DRB, ERASE CODES, START ENGINE, AND ALLOW ENGINE TO IDLE FOR 30 SECONDS.

WITH THE DRB, READ CODES.

DOES THE DRB SHOW "NO CHANGE IN MAP FROM START TO RUN"?

YES

CONTINUE TEST TC-39A ON NEXT PAGE.

NO

T E S T S

NOTE: THE ENGINE IS STILL RUNNING.

WITH THE DRB, SET THE ENGINE SPEED TO 1500 RPM.

WITH THE ENGINE RPM AT 1500, READ MAP SENSOR VOLTAGE.

WHILE MONITORING THE VOLTAGE, WIGGLE THE WIRING FROM THE MAP SENSOR TO THE PCM.

DID THE ENGINE STALL OR VOLTAGE BECOME ERRATIC?

YES

REPAIR THE WIRING OR CONNECTOR DEFECT BETWEEN THE MAP SENSOR AND THE PCM.*

NO

STOP ACTUATION.

WHILE MONITORING THE DRB DISPLAY, SNAP THE THROTTLE OPEN AND CLOSED.

DID THE VACUUM DROP RAPIDLY BELOW 1.0"?

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT.TEST COMPLETE.* FIG. 1

NO

REMOVE MAP SENSOR AND INSPECT CONDITON OF VACUUM PORT. SEE GENERAL INFO 4.4

ALSO INSPECT CONDITION OF INTAKE MANIFOLD OR THROTTLE BODY VACUUM PORT.

IS THERE A RESTRICTION OR DEFECT IN THE VACUUM PORTS?

YES

REPAIR THE RESTRICTED OR DEFECTIVE VACUUM PORTS.*

NO

REPLACE MAP SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
239

T TEST TC-39A CONTINUED - REPAIRING - NO CHANGE IN MAP FROM START TO RUN R O U AB, AN, BR AND XJ BODIES B L E C O D E T E S T S
FIG. 1
BR 8.0L

FIG. 2
ZJ BODY

FIG. 3
240

TEST TC-39A CONTINUED - REPAIRING - NO CHANGE IN MAP FROM START TO RUN

T R O U B L E C O D E T E S T S

TEST TC-39A CONTINUED FROM PREVIOUS PAGE.

IGNITION KEY ON. (ENGINE OFF)

REMOVE MAP SENSOR AND INSPECT CONDITON OF VACUUM PORT. SEE GENERAL INFO 4.4

ALSO INSPECT CONDITON OF INTAKE MANIFOLD OR THROTTLE BODY VACUUM PORT.

WAS THERE A RESTRICTION?

YES

REMOVE THE RESTRICTION AND REINSTALL THE MAP SENSOR.*

NO

USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE MAP SENSOR 5-VOLT SUPPLY CIRCUIT. FIG. 1, 2 0R 3

IS THE VOLTAGE ABOVE 4.5 VOLTS?

NO

REPAIR THE OPEN MAP SENSOR 5-VOLT SUPPLY CIRCUIT.*

YES

REPLACE THE MAP SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
241

T TEST TC-40A REPAIRING - NO CRANK REFERENCE SIGNAL AT PCM R O Perform DTC TEST Before Proceeding U 5.9L DIESEL B L E C O D E T E S T S

FIG. 1
ALL OTHERS

FIG. 2
242

TEST TC-40A REPAIRING - NO CRANK REFERENCE SIGNAL AT PCM
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-40A

WITH THE DRB, READ THE CURRENT CKP COUNT AND ATTEMPT TO START THE ENGINE.

DOES THE CURRENT CKP COUNT CHANGE WHILE ATTEMPTING TO START THE ENGINE? YES

NO

CONTINUE TEST TC-40A ON THE NEXT PAGE.

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1 OR 2

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WIGGLE THE WIRING HARNESS FROM CKP SENSOR TO THE POWERTRAIN CONTROL MODULE.

DID THE ENGINE DIE OUT WHEN WIGGLING WIRES? NO

YES

REPAIR CIRCUIT AS NECESSARY WHERE WIGGLING CAUSED THE ENGINE TO DIE OUT.*

REFER TO GENERAL INFO 3.3.2 FOR INACTIVE TROUBLE CODE INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
243

T TEST TC-40A CONTINUED - REPAIRING - NO CRANK REFERENCE SIGNAL AT PCM R O U AB, AN AND BR BODIES XJ BODY B L E C O D E T E S T S
FIG. 1
ZJ BODY

FIG. 2
AB, AN AND BR BODIES

FIG. 3
XJ BODY ZJ BODY

FIG. 4

FIG. 5
244

FIG. 6

TEST TC-40A CONTINUED - REPAIRING - NO CRANK REFERENCE SIGNAL AT PCM

TEST TC-40A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE CRANKSHAFT POSITION SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR AS NECESSARY.*

T R O U B L E C O D E

NO

TURN IGNITION ON.

USING A VOLTMETER, MEASURE THE 5-VOLT SUPPLY CIRCUIT. FIG. 1, 2 0R 3

IS THE VOLTAGE ABOVE 4.5 VOLTS?

NO

CONTINUE TEST TC-40A ON THE NEXT PAGE.

YES

T E S T S

TURN IGNITION OFF. USING AN OHMMETER, MEASURE THE SENSOR GROUND CIRCUIT...

FROM THE CKP SENSOR CONNECTOR TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

YES

DISCONNECT THE PCM BLACK CONNECTOR. INSPECT ALL TERMINALS.** SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE CKP SIGNAL CIRCUIT...

FROM THE PCM TO THE CKP CONNECTOR. FIG. 4, 5 OR 6

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN CKP SIGNAL CIRCUIT.*

YES

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE CKP SIGNAL CIRCUIT...

AND GROUND AT THE PCM CONNECTOR. FIG. 4, 5 OR 6

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPLACE THE CRANKSHAFT POSITION SENSOR.*

YES

REPAIR THE CKP SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
245

T TEST TC-40A CONTINUED - REPAIRING - NO CRANK REFERENCE SIGNAL AT PCM R O U AB, AN AND BR BODIES B L E C O D E T E S T S
FIG. 1
XJ BODY

FIG. 2
ZJ BODY

FIG. 3
246

TEST TC-40A CONTINUED - REPAIRING - NO CRANK REFERENCE SIGNAL AT PCM

T R O U B L E C O D E T E S T S

TEST TC-40A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF. DISCONNECT THE PCM BLACK CONNECTOR. INSPECT ALL TERMINALS.** SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE 5-VOLT SUPPLY CIRCUIT...

FROM THE PCM TO THE CKP SENSOR CONNECTOR. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN 5-VOLT SUPPLY CIRCUIT.*

YES

USING AN OHMMETER, MEASURE THE 5-VOLT SUPPLY CIRCUIT...

FROM THE CKP SENSOR CONNECTOR TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE 5-VOLT SUPPLY CIRCUIT FOR A SHORT TO GROUND.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
247

T TEST TC-41A REPAIRING - IGNITION COIL #3 PRIMARY CIRCUIT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2

FIG. 3
248

FIG. 4

TEST TC-41A REPAIRING - IGNITION COIL #3 PRIMARY CIRCUIT
Perform DTC TEST Before Proceeding

START TEST TC-41A

TURN IGNITION OFF.

T R O U B L E C O D E

DISCONNECT THE SPARK PLUG CABLE AT SPARK PLUG #8. FIG. 1

CONNECT CABLE TO A SPARK PLUG TESTER. FIG. 2

T E S T S

CONNECT THE SPARK PLUG TESTER TO A GOOD GROUND.

TURN IGNITION ON. (ENGINE OFF)

WITH THE DRB, ACTUATE IGNITION COIL #3.

IS THERE GOOD SPARK?

NO

CONTINUE TEST TC-41A ON THE NEXT PAGE.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 3

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WIGGLE WIRING HARNESS FROM THE REAR COIL PACK TO THE POWERTRAIN CONTROL MODULE.

DOES THE SPARK BECOME ERRATIC OR STOP?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED PROBLEM TO APPEAR.*

NO

REFER TO FIGURE 4 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
249

T TEST TC-41A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - IGNITION COIL #3 PRIMARY CIRCUIT

FIG. 1

FIG. 2

FIG. 3
250

TEST TC-41A CONTINUED - REPAIRING - IGNITION COIL #3 PRIMARY CIRCUIT

TEST TC-41A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE REAR IGNITION COIL CONNECTOR.** SEE GENERAL INF0 4.0

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED? FIG. 1 NO

YES

REPAIR AS NECESSARY.*

T R O U B L E C O D E

KEY ON, WITH THE DRB, ACTUATE IGNITION COIL #3.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

T E S T S

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE IGNITION COIL #3 PRIMARY CIRCUIT TO GROUND. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IGNITION COIL #3 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE IGNITION COIL #3 DRIVER CIRCUIT FROM THE PCM CONNECTOR...

TO THE REAR IGNITION COIL CONNECTOR. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN IGNITION COIL #3 DRIVER CIRCUIT.*

YES

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE IGNITION COIL #3 PRIMARY CIRCUIT FOR RESISTANCE. FIG. 3

IS THE RESISTANCE BELOW 2.0 OHMS?

NO

REPLACE THE REAR IGNITION COIL.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
251

T TEST TC-42A REPAIRING - IGNITION COIL #2 PRIMARY CIRCUIT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2

FIG. 3
252

FIG. 4

TEST TC-42A REPAIRING - IGNITION COIL #2 PRIMARY CIRCUIT
Perform DTC TEST Before Proceeding

START TEST TC-42A

TURN IGNITION OFF.

T R O U B L E C O D E

DISCONNECT THE SPARK PLUG CABLE AT SPARK PLUG #5. FIG. 1

CONNECT CABLE TO A SPARK TESTER. FIG. 2

CONNECT SPARK TESTER TO A GOOD GROUND.

T E S T S

TURN IGNITION ON. (ENGINE OFF)

WITH THE DRB, ACTUATE IGNITION COIL #2.

IS THERE GOOD SPARK?

NO

CONTINUE TEST TC-42A ON THE NEXT PAGE.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 3

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WIGGLE WIRING HARNESS FROM THE REAR COIL PACK TO THE POWERTRAIN CONTROL MODULE.

DOES THE SPARK BECOME ERRATIC OR STOP?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED PROBLEM TO APPEAR.*

NO

REFER TO FIGURE 4 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
253

T TEST TC-42A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - IGNITION COIL #2 PRIMARY CIRCUIT

FIG. 1

FIG. 2

FIG. 3
254

TEST TC-42A CONTINUED - REPAIRING - IGNITION COIL #2 PRIMARY CIRCUIT

TEST TC-42A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE REAR IGNITION COIL CONNECTOR.** SEE GENERAL INFO 4.0

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED? FIG. 1 NO

YES

REPAIR AS NECESSARY.*

T R O U B L E C O D E

KEY ON, WITH THE DRB, ACTUATE IGNITION COIL #2.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

T E S T S

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE IGNITION COIL #2 PRIMARY CIRCUIT TO GROUND. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IGNITION COIL #2 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE IGNITION COIL #2 DRIVER CIRCUIT FROM THE PCM CONNECTOR...

TO THE REAR IGNITION COIL CONNECTOR. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN IGNITION COIL #2 DRIVER CIRCUIT.*

YES

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE IGNITION COIL #2 PRIMARY CIRCUIT FOR RESISTANCE. FIG. 3

IS THE RESISTANCE BELOW 2.0 OHMS?

NO

REPLACE THE REAR IGNITION COIL.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
255

T TEST TC-43A REPAIRING - IGNITION COIL #1 PRIMARY CIRCUIT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG.1

FIG. 2

FIG. 3
256

FIG. 4

TEST TC-43A REPAIRING - IGNITION COIL #1 PRIMARY CIRCUIT
Perform DTC TEST Before Proceeding

START TEST TC-43A

DOES THE VEHICLE HAVE A V-10 ENGINE?

NO

PREFORM TEST TC-43B.

T R O U B L E C O D E T E S T S

YES

KEY OFF. DISCONNECT THE SPARK PLUG CABLE AT SPARK PLUG #6. FIG. 1

CONNECT CABLE TO SPARK TESTER. FIG. 2

CONNECT SPARK TESTER TO A GOOD GROUND.

TURN IGNITION ON. (ENGINE OFF)

WITH THE DRB ACTUATE IGNITION COIL #1.

IS THERE GOOD SPARK?

NO

CONTINUE TEST TC-43A ON THE NEXT PAGE.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 3

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WIGGLE WIRING HARNESS FROM THE FRONT COIL PACK TO THE POWERTRAIN CONTROL MODULE.

DOES THE SPARK BECOME ERRATIC OR STOP?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED PROBLEM TO APPEAR.*

NO

REFER TO FIGURE 4 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
257

T TEST TC-43A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - IGNITION COIL #1 PRIMARY CIRCUIT

FIG. 1

FIG. 2

FIG. 3
258

TEST TC-43A CONTINUED - REPAIRING - IGNITION COIL #1 PRIMARY CIRCUIT

TEST TC-43A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE FRONT IGNITION COIL CONNECTOR.** SEE GENERAL INFO 4.0

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED? FIG. 1 NO

YES

REPAIR AS NECESSARY.*

T R O U B L E C O D E

KEY ON, WITH THE DRB, ACTUATE IGNITION COIL #1.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

T E S T S

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE IGNITION COIL #1 PRIMARY CIRCUIT TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IGNITION COIL #1 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE IGNITION COIL #1 DRIVER CIRCUIT FROM THE PCM CONNECTOR...

TO THE FRONT IGNITION COIL CONNECTOR. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN IGNITION COIL #1 DRIVER CIRCUIT.*

YES

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE IGNITION COIL #1 PRIMARY CIRCUIT FOR RESISTANCE. FIG. 3

IS THE RESISTANCE BELOW 2.0 OHMS?

NO

REPLACE THE FRONT IGNITION COIL.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
259

T TEST TC-43B REPAIRING - IGNITION COIL #1 PRIMARY CIRCUIT R O Perform DTC TEST Before Proceeding U BR BODY AB, AN AND XJ BODIES B L E C O D E T E S T S

FIG. 1
ZJ BODY

FIG. 2

FIG. 3
260

FIG. 4

TEST TC-43B REPAIRING - IGNITION COIL #1 PRIMARY CIRCUIT
Perform DTC TEST Before Proceeding

START TEST TC-43B.

KEY OFF, DISCONNECT THE IGNITION COIL CONNECTOR.** SEE GENERAL INFO 4.0

T R O U B L E
YES REPAIR AS NECESSARY.*

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED?

NO

C O D E T E S T S

KEY ON, WITH THE DRB, ACTUATE IGNITION COIL #1.

WITH A VOLTMETER, MEASURE THE ASD OUTPUT CIRCUIT. FIG. 1, 2 OR 3

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD OUTPUT CIRCUIT.*

YES

USE AN OHMMETER IN THE FOLLOWING STEPS.

TEST THE IGNITION COIL PRIMARY CIRCUIT FOR RESISTANCE. FIG. 4

IS THE RESISTANCE BELOW 2.0 OHMS?

NO

REPLACE THE IGNITION COIL.*

YES

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

MEASURE THE RESISTANCE OF THE IGNITION COIL DRIVER CKT TO GND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IGNITION COIL #1 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

CONTINUE TEST TC-43B ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
261

T TEST TC-43B CONTINUED - REPAIRING - IGNITION COIL #1 PRIMARY CIRCUIT R O U AB AND AN BODIES BR BODY B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
262

FIG. 4

TEST TC-43B CONTINUED - REPAIRING - IGNITION COIL #1 PRIMARY CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-43B CONTINUED FROM THE PREVIOUS PAGE.

USE AN OHMMETER IN THE FOLLOWING STEP.

TEST THE IGNITION COIL #1 DRIVER CIRCUIT FOR RESISTANCE. FIG. 1, 2, 3 OR 4.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN IGNITION COIL #1 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
263

T TEST TC-44A REPAIRING - NO ASD RELAY OUTPUT VOLTAGE AT PCM R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
264

TEST TC-44A REPAIRING - NO ASD RELAY OUTPUT VOLTAGE AT PCM
Perform DTC TEST Before Proceeding

START TEST TC-44A.

IS A TROUBLE CODE ALSO SET FOR "AUTO SHUTDOWN RELAY CONTROL CIRCUIT"?

T R O U B L E
PERFORM TEST TC-10A.

YES

NO

C O D E T E S T S

WITH THE DRB, ERASE CODES.

START ENGINE, ALLOW ENGINE TO IDLE FOR AT LEAST 10 SECONDS. RE-READ CODES.

DOES THE DRB SHOW "NO ASD RELAY OUTPUT VOLTAGE AT PCM" WITH A START/RUN COUNT OF ZERO? NO

YES

CONTINUE TEST TC-44A ON THE NEXT PAGE.

THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

ERASE FAULT CODES. START ENGINE AND LET IDLE.

WIGGLE WIRING HARNESS FROM ASD RELAY TO THE PCM. RE-CHECK FAULT CODES.

DID WIGGLING CAUSE THE FAULT CODE TO APPEAR?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED THE FAULT CODE TO APPEAR.*

NO

REFER TO FIGURE 2 FOR INACTIVE TROUBLE CODE CONDITION INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
265

T TEST TC-44A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - NO ASD RELAY OUTPUT VOLTAGE AT PCM
AN BODY

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
266

TEST TC-44A CONTINUED - REPAIRING - NO ASD RELAY OUTPUT VOLTAGE AT PCM

TEST TC-44A CONTINUED FROM THE PREVIOUS PAGE.

IS THE VEHICLE EQUIPPED WITH A DIESEL ENGINE? NO

YES

PERFORM TEST TC-44B

T R O U B L E C O D E

ATTEMPT TO START THE VEHICLE.

DID THE ENGINE START?

YES

CONTINUE TEST TC-44A ON THE NEXT PAGE.

NO

T E S T S

DISCONNECT THE AUTO SHUTDOWN RELAY.** SEE GENERAL INFO 4.4

USING A VOLTMETER, MEASURE THE FUSED B(+) CIRCUIT. FIG. 1, 2, 3, 4 OR 5

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+) CIRCUIT.*

YES

INSTALL A SUBSTITUTE RELAY FOR THE AUTO SHUTDOWN RELAY.

ATTEMPT TO START THE VEHICLE.

DID THE ENGINE START?

YES

REPLACE THE ORIGINAL AUTO SHUTDOWN RELAY.*

NO

IGNITION OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE GREY CONN.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE ASD RELAY OUTPUT CIRCUIT...

FROM THE RELAY TO THE PCM. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR OPEN ASD RELAY OUTPUT CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
267

T TEST TC-44A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - NO ASD RELAY OUTPUT VOLTAGE AT PCM
AN BODY

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
268

TEST TC-44A CONTINUED - REPAIRING - NO ASD RELAY OUTPUT VOLTAGE AT PCM

T R O U B L E C O D E T E S T S

TEST TC-44A CONTINUED FROM THE PREVIOUS PAGE.

IGNITION OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE GREY CONN.** SEE GENERAL INFO 4.1

DISCONNECT THE AUTO SHUTDOWN RELAY.** SEE GENERAL INFO 4.6

USING AN OHMMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT...

FROM THE RELAY TO THE PCM. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR OPEN ASD RELAY OUTPUT CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
269

T TEST TC-44B REPAIRING - NO ASD RELAY OUTPUT VOLTAGE AT PCM R O Perform TEST TC-44A Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
270

TEST TC-44B REPAIRING - NO ASD RELAY OUTPUT VOLTAGE AT PCM
Perform TEST TC-44A Before Proceeding

START TEST TC-44B.

DISCONNECT THE AUTO SHUTDOWN RELAY.** FIG.1

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE FUSED B(+) CIRCUIT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+) CIRCUIT.*

YES

T E S T S

ERASE FAULT CODES. INSTALL A SUBSTITUTE RELAY FOR THE AUTO SHUTDOWN RELAY.

START ENGINE. LET IDLE FOR AT LEAST 10 SECONDS.

DID THE FAULT CODE "NO ASD RELAY OUTPUT VOLTAGE AT PCM" RETURN?

NO

REPLACE THE ORIGINAL AUTO SHUTDOWN RELAY.*

YES

IGNITION OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE GREY CONN.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT...

FROM THE PCM TO THE RELAY. FIG. 2

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR OPEN ASD RELAY OUTPUT CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
271

T TEST TC-48A REPAIRING - PCM FAILURE SRI MILE NOT STORED R O Perform DTC TEST Before Proceeding U B L START TEST WITH THE DRB DOES THE DRB E TC-48A. PERFORM THE SRI DISPLAY "WRITE
MEMORY TEST. FAILURE"?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

C O D E T E S T S
NO

NO

DOES THE DRB DISPLAY "WRITE REFUSED"?

YES

WITH THE DRB, PERFORM THE SRI MEMORY TEST A SECOND TIME.

DOES THE DRB DISPLAY "WRITE REFUSED" AGAIN?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

DOES THE DRB DISPLAY "SRI MILEAGE INVALID"?

YES

UPDATE THE MILEAGE AND RETEST THE SRI MEMORY.*

NO

COMPARE SRI MILEAGE STORED VALUE TO THE INSTRUMENT PANEL ODOMETER MILEAGE.

IS THE MILEAGE WITHIN THE DRB SPECIFED RANGE?

YES

RETEST THE SRI MEMORY.*

NO

UPDATE THE MILEAGE AND RETEST THE SRI MEMORY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
272

TEST TC-49A REPAIRING - EEPROM WRITE DENIED
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-49A.

WITH THE DRB, PERFORM THE SRI MEMORY TEST.

DOES THE DRB DISPLAY "WRITE REFUSED"?

NO TEST COMPLETE.*

YES

WITH THE DRB, PERFORM THE SRI MEMORY TEST A SECOND TIME.

DOES THE DRB DISPLAY "WRITE REFUSED" AGAIN?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
273

T TEST TC-50A REPAIRING - TRANS 3-4 SOLENOID/TRANS RELAY CKTS R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
274

TEST TC-50A REPAIRING - TRANS 3-4 SOLENOID/TRANS RELAY CKTS
Perform DTC TEST Before Proceeding

START TEST TC-50A.

IS THE TRANS 12-VOLT SUPPLY RELAY CONTROL CIRCUIT CODE SET?

T R O U B L E
PERFORM TEST TC-173.

YES

NO

C O D E T E S T S

ROAD TEST VEHICLE. ATTAIN VEHICLE SPEED OF AT LEAST 50 MPH.

PUSH OD SWITCH 4 TIMES SUCH THAT VEHICLE ATTEMPTS TO SHIFT FROM 4TH TO 3RD AND BACK.

DID THE VEHICLE SHIFT BETWEEN 3RD AND 4TH?

NO

CONTINUE TEST TC-50A ON THE NEXT PAGE.

YES

AT THIS TIME THE CONDITION REQUIRED TO SET THIS CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH DRB, CLEAR CODES. START THE ENGINE.

WHILE READING DTC’S WITH THE DRB, WIGGLE THE WIRING HARNESS FROM THE SOLENOID TO THE PCM.

DOES THE 3-4 SOLENOID CONTROL CIRCUIT FAULT CODE APPEAR?

YES

REPAIR WIRING AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
275

T TEST TC-50A R O U AB BODY B L E C O D E T E S T S

CONTINUED - TRANS 3-4 SOLENOID/TRANS RELAY CKTS
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
276

FIG. 4

TEST TC-50A CONTINUED - TRANS 3-4 SOLENOID/TRANS RELAY CKTS

T R O U B L E C O D E T E S T S

TEST TC-50A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE TRANS SOLENOID PACK CONNECTOR.** SEE GENERAL INFO 4.2

KEY ON, WITH THE DRB, ACTUATE TRANS CONTROL RELAY.

MEASURE THE VOLTAGE AT THE TRANS RELAY OUTPUT CIRCUIT. FIG. 1, 2, 3 OR 4

DOES THE VOLTAGE FLUCTUATE FROM 0 VOLTS TO OVER 10.0 VOLTS?

NO

PERFORM TEST TC-50B.

YES

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE WHITE CONNECTOR.**

KEY ON. MEASURE THE VOLTAGE AT THE 3-4 SHIFT SOLENOID CONTROL CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

PERFORM TEST TC-50D.

NO

CONTINUE TEST TC-50A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
277

T TEST TC-50A R O U AB BODY B L E C O D E T E S T S

CONTINUED - TRANS 3-4 SOLENOID/TRANS RELAY CKTS
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
278

FIG. 4

TEST TC-50A CONTINUED - TRANS 3-4 SOLENOID/TRANS RELAY CKTS

TEST TC-50A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF. MEASURE THE RESISTANCE BETWEEN THE 3-4 SHIFT SOLENOID CONTROL CIRCUIT...

T R O U B L E C O D E T E S T S

AT THE PCM CONNECTOR AND GROUND. FIG. 1,2,3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE 3-4 SHIFT SOLENOID CONTROL CIRCUIT SHORTED TO GROUND.*

NO

RECONNECT THE SOLENOID PACK CONNECTOR.

MEASURE THE RESISTANCE BETWEEN THE 3-4 SHIFT SOLENOID CONTROL CIRCUIT...

AT THE PCM CONNECTOR AND GROUND. FIG. 1,2,3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

RELACE THE SOLENOID AND HARNESS ASSEMBLY.*

NO

CONTINUE TEST TC-50A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
279

T TEST TC-50A R O U AB BODY B L E C O D E T E S T S

CONTINUED - TRANS 3-4 SOLENOID/TRANS RELAY CKTS
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
280

FIG. 4

TEST TC-50A CONTINUED - TRANS 3-4 SOLENOID/TRANS RELAY CKTS

T R O U B L E C O D E T E S T S

TEST TC-50A CONTINUED FROM THE PREVIOUS PAGE.

REMOVE THE TRANS CONTROL RELAY.** SEE GENERAL INFO 4.6

MEASURE THE RESISTANCE BETWEEN THE TRANS CONTROL RELAY OUTPUT CIRCUIT AT THE RELAY...

AND THE 3-4 SOLENOID CONTROL CIRCUIT AT THE PCM CONNECTOR. FIG. 1,2,3 OR 4

IS THE RESISTANCE BETWEEN 26.0 AND 40.0 OHMS?

YES REPLACE THE PCM.*

NO

IS THE RESISTANCE ABOVE 40.0 OHMS?

NO

PERFORM TEST TC-50C.

YES

CONTINUE TEST TC-50A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
281

T TEST TC-50A R O U AB BODY B L E C O D E T E S T S

CONTINUED - TRANS 3-4 SOLENOID/TRANS RELAY CKTS
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
282

FIG. 4

TEST TC-50A CONTINUED - TRANS 3-4 SOLENOID/TRANS RELAY CKTS

T R O U B L E C O D E T E S T S

TEST TC-50A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE TRANS SOLENOID PACK CONNECTOR.** SEE GENERAL INFO 4.2

MEASURE THE RESISTANCE OF THE 3-4 SOLENOID CONTROL CIRCUIT...

FROM THE PCM CONNECTOR TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN 3-4 SOLENOID CONTROL CIRCUIT.*

YES

REPLACE THE SOLENOID AND HARNESS ASSEMBLY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
283

T TEST TC-50B REPAIRING - TRANS 3-4 SOLENOID/TRANS RELAY CKTS R O Perform TEST TC-50A Before Proceeding U AB BODY AN BODY B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
284

FIG. 4

TEST TC-50B REPAIRING - TRANS 3-4 SOLENOID/TRANS RELAY CKTS
Perform TEST TC-50A Before Proceeding

START TEST TC-50B.

REMOVE THE TRANS CONTROL RELAY.** SEE GENERAL INFO 4.6

T R O U B L E C O D E T E S T S

KEY OFF. MEASURE THE RESISTANCE BETWEEN THE...

TRANS CONTROL RELAY OUTPUT CIRCUIT AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE TRANS RELAY OUTPUT CIRCUIT SHORTED TO GROUND.*

NO

MEASURE THE RESISTANCE OF THE TRANS CONTROL RELAY OUTPUT CIRCUIT...

FROM THE RELAY CONNECTOR TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN TRANS RELAY OUTPUT CIRCUIT.*

NO

KEY ON, MEASURE THE VOLTAGE AT THE FUSED B(+) CIRCUIT IN THE RELAY CONNECTOR. FIG. 1, 2, 3 OR 4

IS VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+) FEED TO THE TRANS CONTROL RELAY.*

YES

REPLACE THE TRANS CONTROL RELAY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
285

T TEST TC-50C CONTINUED - TRANS 3-4 SOLENOID/TRANS RELAY CKTS R O Perform TEST TC-50A Before Proceeding U AB BODY AN BODY B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
286

FIG. 4

TEST TC-50C CONTINUED - TRANS 3-4 SOLENOID/TRANS RELAY CKTS
Perform TEST TC-50A Before Proceeding

START TEST TC-50C.

DISCONNECT THE TRANS SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

DISCONNECT ALL PCM CONNECTORS.** SEE GENERAL INFO 4.1

T R O U B L E C O D E T E S T S

MEASURE AND RECORD THE RESISTANCES BETWEEN THE 3-4 SHIFT SOLENOID CONTROL CIRCUIT...

AND ALL OTHER CIRCUITS IN THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS BETWEEN ANY TWO CIRCUITS?

REPAIR 3-4 SOLENOID YES CONTROL CKT SHORTED TO CIRCUIT(S) THAT MEASURED BELOW 5.0 OHMS.

NO

REPLACE THE SOLENOID HARNESS INSIDE THE TRANSMISSION AND THE SOLENOID PACK.*

CONNECT ALL DISCONNECTED CONNECTORS.

ROAD TEST VEHICLE. ATTAIN VEHICLE SPEED OF AT LEAST 50 MPH.

PUSH OD SWITCH 4 TIMES SUCH THAT VEHICLE ATTEMPTS TO SHIFT FROM 4TH TO THIRD AND BACK.

DID THE VEHICLE SHIFT BETWEEN 3RD AND 4TH?

NO REPLACE THE PCM.*

YES

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
287

T TEST TC-50D REPAIRING - TRANS 3-4 SOLENOID/TRANS RELAY CKTS R O Perform TEST TC-50A Before Proceeding U NOTES B L E C O D E T E S T S

288

TEST TC-50D REPAIRING - TRANS 3-4 SOLENOID/TRANS RELAY CKTS
Perform TEST TC-50A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-50D.

REPAIR 3-4 SOLENOID CONTROL CIRCUIT SHORTED TO VOLTAGE.*

CONNECT ALL DISCONNECTED CONNECTORS.

ROAD TEST VEHICLE. ATTAIN VEHICLE SPEED OF AT LEAST 50 MPH.

PUSH OD SWITCH 4 TIMES SUCH THAT VEHICLE ATTEMPTS TO SHIFT FROM 4TH TO 3RD AND BACK.

DID THE VEHICLE SHIFT BETWEEN 3RD AND 4TH?

NO REPLACE THE PCM.*

YES

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
289

T TEST TC-55A REPAIRING - INJECTOR #9 CONTROL CIRCUIT R O Perform TEST TC-21A Before Proceeding U BR BODY B L E C O D E T E S T S

FIG. 1
BR BODY BR BODY

FIG. 2

FIG. 3
290

FIG. 4

TEST TC-55A REPAIRING - INJECTOR #9 CONTROL CIRCUIT
Perform TEST TC-21A Before Proceeding

START TEST TC-55A

KEY OFF, DISCONNECT THE INJECTOR #9 CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #9. FIG. 1

IS THE RESISTANCE BETWEEN 10.0 AND 16.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

T E S T S

KEY ON, WITH THE DRB, ACTUATE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #9 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #9 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #9 DRIVER CIRCUIT... FIG. 4

FROM THE POWERTRAIN CONTROL MODULE CONNECTOR TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #9 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
291

T TEST TC-56A REPAIRING - INJECTOR #10 CONTROL CIRCUIT R O Perform TEST TC-21A Before Proceeding U BR BODY B L E C O D E T E S T S

FIG. 1
BR BODY BR BODY

FIG. 2

FIG. 3
292

FIG. 4

TEST TC-56A REPAIRING - INJECTOR #10 CONTROL CIRCUIT
Perform TEST TC-21A Before Proceeding

START TEST TC-56A

NOTE: ON SOME ENGINES, IT MAY BE NECESSARY TO REMOVE THE INTAKE PLENUM. SEE SERVICE MANUAL.

T R O U B L E C O D E

KEY OFF, DISCONNECT THE INJECTOR #10 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #10. FIG. 1

IS THE RESISTANCE BETWEEN 10.0 AND 16.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

T E S T S

KEY ON, WITH THE DRB, ACTUATE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #10 DRIVER CKT IN THE PCM TO GROUND. FIG. 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #10 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #10 DRIVER CIRCUIT. FIG. 4

FROM THE POWERTRAIN CONTROL MODULE CONNECTOR TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #10 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
293

T TEST TC-57A REPAIRING - INTAKE AIR TEMP SENSOR VOLTAGE LOW R O Perform DTC TEST Before Proceeding U CNG AND GAS ENGINES B L E C O D E T E S T S

FIG. 1
DIESEL ENGINES

FIG. 2
294

FIG. 3

TEST TC-57A REPAIRING - INTAKE AIR TEMP SENSOR VOLTAGE LOW
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-57A.

WITH THE DRB, READ THE INTAKE AIR TEMPERATURE SENSOR VOLTAGE.

IS THE INTAKE AIR TEMPERATURE SENSOR VOLTAGE BELOW 0.5 VOLT?

YES

CONTINUE TEST TC-57A ON THE NEXT PAGE.

NO

WIGGLE THE INTAKE AIR TEMP SENSOR CONNECTOR & HARNESS.

MONITOR THE DRB DISPLAY.

WAS THERE ANY INTAKE AIR TEMPERATURE SENSOR VOLTAGE CHANGE?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1 OR 2

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 3 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
295

T TEST TC-57A CONTINUED - REPAIRING - INTAKE AIR TEMP SENSOR VOLTAGE LOW R O U AB, AN AND BR BODIES B L E C O D E T E S T S
FIG. 1
XJ BODY

FIG. 2
ZJ BODY

FIG. 3
296

TEST TC-57A CONTINUED - REPAIRING - INTAKE AIR TEMP SENSOR VOLTAGE LOW

TEST TC-57A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE INTAKE AIR TEMPERATURE SENSOR.** SEE GENERAL INFO 4.4

T R O U B L E C O D E

WITH THE DRB, READ THE INTAKE AIR TEMPERATURE SENSOR VOLTAGE.

IS THE INTAKE AIR TEMPERATURE SENSOR VOLTAGE ABOVE 4.0 VOLTS?

YES

REPLACE THE INTAKE AIR TEMPERATURE SENSOR.*

NO

T E S T S

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE RESISTANCE BETWEEN THE SENSOR SIGNAL AND SENSOR GND CKT. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE SENSOR SIGNAL CIRCUIT FOR A SHORT TO SENSOR GROUND.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE IAT SENSOR...

SIGNAL CIRCUIT TO GROUND. FIG. 1,2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
297

T TEST TC-58A REPAIRING - INTAKE AIR TEMP SENSOR VOLTAGE HIGH R O Perform DTC TEST Before Proceeding U CNG AND GAS ENGINES B L E C O D E T E S T S

FIG. 1
DIESEL ENGINES

FIG. 2
298

FIG. 3

TEST TC-58A REPAIRING - INTAKE AIR TEMP SENSOR VOLTAGE HIGH
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-58A.

WITH THE DRB, READ THE INTAKE AIR TEMPERATURE SENSOR VOLTAGE.

IS THE INTAKE AIR TEMPERATURE SENSOR VOLTAGE ABOVE 4.5 VOLTS?

YES

CONTINUE TEST TC-58A ON THE NEXT PAGE.

NO

WIGGLE THE INTAKE AIR TEMP SENSOR CONNECTOR & HARNESS.

MONITOR DRB DISPLAY.

WAS THERE ANY INTAKE AIR TEMPERATURE SENSOR VOLTAGE CHANGE?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1 OR 2

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 3 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
299

T TEST TC-58A CONTINUED - REPAIRING - INTAKE AIR TEMP SENSOR VOLTAGE HIGH R O U AB, AN AND BR BODIES XJ BODY B L E C O D E T E S T S
FIG. 1
ZJ BODY

FIG. 2
AB, AN AND BR BODIES

FIG. 3
XJ BODY ZJ BODY

FIG. 4

FIG. 5
300

FIG. 6

TEST TC-58A CONTINUED - REPAIRING - INTAKE AIR TEMP SENSOR VOLTAGE HIGH

TEST TC-58A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE INTAKE AIR TEMPERATURE (IAT) SENSOR.** SEE GENERAL INFO 4.4

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE VOLTAGE OF THE IAT SIGNAL CIRCUIT. FIG. 1, 2 OR 3

IS THE VOLTAGE ABOVE 6.0 VOLT?

YES

REPAIR IAT SIGNAL CIRCUIT SHORTED TO VOLTAGE.*

NO

T E S T S

CONNECT A JUMPER WIRE ACROSS THE IAT SIGNAL AND SENSOR GROUND CIRCUITS. FIG. 1, 2 OR 3

WITH THE DRB, READ THE INTAKE AIR TEMPERATURE SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 1.0 VOLT?

YES

REPLACE THE INTAKE AIR TEMPERATURE SENSOR.*

NO

MOVE THE JUMPER WIRE FROM THE SENSOR GROUND TO AN ENGINE GROUND. FIG. 1, 2 OR 3

READ THE INTAKE AIR TEMPERATURE SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 1.0 VOLT?

YES

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

NO

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE IAT SENSOR SIGNAL FOR RESISTANCE...

FROM THE PCM TO THE INTAKE AIR TEMPERATURE SENSOR CONNECTOR. FIG. 4, 5 OR 6

IS THE RESISTANCE BELOW 5.O OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN INTAKE AIR TEMPERATURE SENSOR SIGNAL CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
301

T TEST TC-61A REPAIRING - INJECTOR #4 CONTROL CIRCUIT R O Perform TEST TC-21A Before Proceeding U AB, AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
302

FIG. 4

TEST TC-61A REPAIRING - INJECTOR #4 CONTROL CIRCUIT
Perform TEST TC-21A Before Proceeding

YES START TEST TC-61A IS THIS A CNG VEHICLE? PERFORM TEST TC-61B.

T R O U B L E C O D E T E S T S

NO

NOTE: ON SOME ENGINES, IT MAY BE NECESSARY TO REMOVE THE INTAKE PLENUM. SEE SERVICE MANUAL.

KEY OFF, DISCONNECT THE INJECTOR #4 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE RESISTANCE OF INJECTOR #4. FIG. 1

IS THE RESISTANCE BETWEEN 10.0 AND 16.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

KEY ON, WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2, 3 OR 4

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

CONTINUE TEST TC-61A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
303

T TEST TC-61A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #4 CONTROL CIRCUIT
AB, AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
304

FIG. 4

TEST TC-61A CONTINUED - REPAIRING - INJECTOR #4 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-61A CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #4 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #4 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #4 DRIVER CIRCUIT... FIG. 2, 3 OR 4

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #4 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
305

T TEST TC-61B REPAIRING - INJECTOR #4 CONTROL CIRCUIT R O Perform TEST TC-61A Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
306

TEST TC-61B REPAIRING - INJECTOR #4 CONTROL CIRCUIT
Perform TEST TC-61A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-61B

KEY OFF, DISCONNECT THE INJECTOR #4 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #4. FIG. 1

IS THE RESISTANCE BETWEEN 3.0 AND 6.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

KEY ON, WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

CONTINUE TEST TC-61B ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
307

T TEST TC-61B R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #4 CONTROL CIRCUIT

FIG. 1

FIG. 2
308

TEST TC-61B CONTINUED - REPAIRING - INJECTOR #4 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-61B CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #4 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #4 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #4 DRIVER CIRCUIT... FIG. 2

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #4 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
309

T TEST TC-62A REPAIRING - 1/1 O2 SENSOR SHORTED TO VOLTAGE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1
5.9L HD AND 8.0L BR ALL OTHERS

310

TEST TC-62A REPAIRING - 1/1 O2 SENSOR SHORTED TO VOLTAGE
Perform DTC TEST Before Proceeding

START TEST TC-62A.

WARM UP ENGINE TO ABOVE 180F, WAIT 4 MINUTES, LEAVE ENGINE RUNNING.

T R O U B L E C O D E T E S T S

WITH THE DRB, READ THE 1/1 O2 SENSOR VOLTAGE.

IS THE 1/1 O2 SENSOR VOLTAGE ABOVE 1.5 VOLTS?

YES

CONTINUE TEST TC-62A ON THE NEXT PAGE.

NO

WIGGLE THE 1/1 O2 SENSOR CONNECTOR AND HARNESS. SEE GENERAL INFO 4.4

WHILE WIGGLING THE HARNESS, WATCH THE DRB DISPLAY.

DID THE 1/1 O2 SENSOR VOLTAGE GO ABOVE 1.5 VOLTS AT ANY TIME?

YES

REPAIR THE HARNESS OR CONNECTOR THAT HAS THE INTERMITTENT SHORT TO VOLTAGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE THERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
311

T TEST TC-62A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - 1/1 O2 SENSOR SHORTED TO VOLTAGE
AN BODY

FIG. 1
5.9L HD AND 8.0L XJ BODY

FIG. 2

FIG. 3
ZJ BODY ALL OTHERS

FIG. 4

FIG. 5
312

FIG. 6

TEST TC-62A CONTINUED - REPAIRING - 1/1 O2 SENSOR SHORTED TO VOLTAGE

TEST TC-62A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE 1/1 O2 SENSOR.** SEE GENERAL INFO 4.4

IS THE TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

T R O U B L E C O D E

NO

WITH THE DRB, READ THE 1/1 O2 SENSOR VOLTAGE.

IS THE VOLTAGE ABOVE 4.97 VOLTS?

NO

REPLACE THE 1/1 O2 SENSOR.*

YES

T E S T S

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTORS.** SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

TURN IGNITION ON. USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE 1/1 02 SENSOR SIGNAL CIRCUIT AT THE PCM CONNECTOR. FIG. 1,2,3,4,5 OR 6

IS THE VOLTAGE ABOVE 5.0 VOLTS?

YES

REPAIR THE 1/1 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE.*

NO

WIGGLE THE O2 SENSOR HARNESS WHILE CHECKING FOR VOLTAGE IN THE O2 SENSOR SIGNAL CIRCUIT.

DID THE VOLTAGE CHANGE WHILE WIGGLING THE HARNESS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE 1/1 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
313

T TEST TC-66A REPAIRING - 2/1 O2 SENSOR SHORTED TO VOLTAGE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1
8.0L MD CAL ALL OTHERS

314

TEST TC-66A REPAIRING - 2/1 O2 SENSOR SHORTED TO VOLTAGE
Perform DTC TEST Before Proceeding

START TEST TC-66A.

WARM UP ENGINE TO ABOVE 180F, WAIT 4 MINUTES, LEAVE ENGINE RUNNING.

T R O U B L E C O D E T E S T S

WITH THE DRB, READ THE 2/1 O2 SENSOR VOLTAGE.

IS THE 2/1 O2 SENSOR VOLTAGE ABOVE 1.5 VOLTS?

YES

CONTINUE TEST TC-66A ON THE NEXT PAGE.

NO

WIGGLE THE 2/1 O2 SENSOR CONNECTOR AND HARNESS. SEE GENERAL INFO 4.4

WHILE WIGGLING THE HARNESS, WATCH THE DRB DISPLAY.

DID THE 2/1 O2 SENSOR VOLTAGE GO ABOVE 1.5 VOLTS AT ANY TIME?

YES

REPAIR THE HARNESS OR CONNECTOR THAT HAS THE INTERMITTENT SHORT TO VOLTAGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE THERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
315

T TEST TC-66A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 2/1 O2 SENSOR SHORTED TO VOLTAGE

FIG. 1

316

TEST TC-66A CONTINUED - REPAIRING - 2/1 O2 SENSOR SHORTED TO VOLTAGE

TEST TC-66A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE 2/1 O2 SENSOR.** SEE GENERAL INFO 4.4

IS THE TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

T R O U B L E C O D E

NO

WITH THE DRB, READ THE 2/1 O2 SENSOR VOLTAGE.

IS THE VOLTAGE ABOVE 4.97 VOLTS?

NO

REPLACE THE 2/1 O2 SENSOR.*

YES

T E S T S

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTORS.** SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

TURN IGNITION ON. USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE 2/1 02 SENSOR SIGNAL CIRCUIT AT THE PCM CONNECTOR. FIG. 1

IS THE VOLTAGE ABOVE 5.0 VOLTS?

YES

REPAIR THE 2/1 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE.*

NO

WIGGLE THE O2 SENSOR HARNESS WHILE CHECKING FOR VOLTAGE IN THE O2 SENSOR SIGNAL CIRCUIT.

DID THE VOLTAGE CHANGE WHILE WIGGLING THE HARNESS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE 2/1 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
317

T TEST TC-69A REPAIRING - INJECTOR #5 CONTROL CIRCUIT R O Perform TEST TC-21A Before Proceeding U AB, AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
318

FIG. 4

TEST TC-69A REPAIRING - INJECTOR #5 CONTROL CIRCUIT
Perform TEST TC-21A Before Proceeding

T R O U B L E C O D E T E S T S
NO REPLACE THE FUEL INJECTOR.*

START TEST TC-69A

IS THIS A CNG VEHICLE?

YES

PERFORM TEST TC-69B.

NO

KEY OFF, DISCONNECT THE INJECTOR #5 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #5. FIG. 1

IS THE RESISTANCE BETWEEN 10.0 AND 16.0 OHMS?

YES

KEY ON, WITH THE DRB, ACTUATE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2, 3 OR 4

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

TEST TC-69A CONTINUED ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
319

T TEST TC-69A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #5 CONTROL CIRCUIT
AB, AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
320

FIG. 4

TEST TC-69A CONTINUED - REPAIRING - INJECTOR #5 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-69A CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #5 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #5 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #5 DRIVER CIRCUIT... FIG. 2, 3 OR 4

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #5 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
321

T TEST TC-69B REPAIRING - INJECTOR #5 CONTROL CIRCUIT R O Perform TEST TC-69A Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2

FIG. 3
322

FIG. 4

TEST TC-69B REPAIRING - INJECTOR #5 CONTROL CIRCUIT
Perform TEST TC-69A Before Proceeding

START TEST TC-69B

KEY OFF, DISCONNECT THE INJECTOR #5 CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #5. FIG. 1

IS THE RESISTANCE BETWEEN 3.0 AND 6.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

T E S T S

KEY ON, WITH THE DRB, ACTUATE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #5 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #5 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #5 DRIVER CIRCUIT... FIG. 4

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #5 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
323

T TEST TC-70A REPAIRING - INJECTOR #6 CONTROL CIRCUIT R O Perform TEST TC-21A Before Proceeding U AB, AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
324

FIG. 4

TEST TC-70A REPAIRING - INJECTOR #6 CONTROL CIRCUIT
Perform TEST TC-21A Before Proceeding

T R O U B L E
YES PERFORM TEST TC-70B.

START TEST TC-70A

IS THIS A CNG VEHICLE?

NO

C O D E T E S T S

NOTE: ON SOME ENGINES, IT MAY BE NECESSARY TO REMOVE THE INTAKE PLENUM. SEE SERVICE MANUAL.

KEY OFF, DISCONNECT THE INJECTOR #6 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #6. FIG. 1

IS THE RESISTANCE BETWEEN 10.0 AND 16.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

KEY ON, WITH THE DRB, ACTUATE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2, 3 OR 4

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

TEST TC-70A CONTINUED ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
325

T TEST TC-70A CONTINUED - REPAIRING - INJECTOR #6 CONTROL CIRCUIT R O U AB, AN, BR AND XJ BODIES ZJ BODY B L E C O D E T E S T S
FIG. 1
AB, AN AND BR BODIES XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
326

TEST TC-70A CONTINUED - REPAIRING - INJECTOR #6 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-70A CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #6 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #6 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #6 DRIVER CIRCUIT... FIG. 3, 4 OR 5

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #6 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
327

T TEST TC-70B REPAIRING - INJECTOR #6 CONTROL CIRCUIT R O Perform TEST TC-70A Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2

FIG. 3
328

FIG. 4

TEST TC-70B REPAIRING - INJECTOR #6 CONTROL CIRCUIT
Perform TEST TC-70A Before Proceeding

START TEST TC-70B

KEY OFF, DISCONNECT THE INJECTOR #6 CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #6. FIG. 1

IS THE RESISTANCE BETWEEN 3.0 AND 6.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

T E S T S

KEY ON, WITH THE DRB, ACTUATE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #6 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #6 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #6 DRIVER CIRCUIT... FIG. 4

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #6 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
329

T TEST TC-74A REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO LOW R O Perform DTC TEST Before Proceeding U AB BODY B L E C O D E T E S T S
FIG. 1
AN BODY BR BODY

FIG. 2
ZJ BODY

FIG. 3

FIG. 4
330

FIG. 5

TEST TC-74A REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO LOW
Perform DTC TEST Before Proceeding

START TEST TC-74A.

KEY OFF. DISCONNECT ALL PCM CONNECTORS.**

T R O U B L E C O D E

MEASURE THE RESISTANCE BETWEEN THE TRANS TEMP SIGNAL CIRCUIT AND THE...

SENSOR GROUND CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 550.0 OHMS?

YES

CONTINUE TEST TC-74A ON THE FOLLOWING PAGE.

NO

T E S T S

IS THE RESISTANCE ABOVE 2300.0 OHMS?

YES

PERFORM TEST TC-75A.

NO

MEASURE THE RESISTANCE BETWEEN THE TRANS TEMP SIGNAL CIRCUIT...

AND GROUND. IS THE RESISTANCE ABOVE 5.0 OHMS? FIG. 1, 2, 3 OR 4 YES NO

CONTINUE TEST TC-74A ON THE FOLLOWING PAGE.

RECONNECT ALL CONNECTORS.

WITH THE DRB, READ TRANS TEMP VOLTAGE.

IS THE VOLTAGE BELOW 1.5 VOLTS.

YES REPLACE THE PCM.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 5

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
331

T TEST TC-74A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO LOW
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
332

FIG. 4

TEST TC-74A CONTINUED - REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO LOW

TEST TC-74A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE TRANSMISSION SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E

USE AN OHMMETER IN THE FOLLOWING STEPS. MEASURE THE RESISTANCE BETWEEN THE TRANS TEMP...

SIGNAL CIRCUIT AND THE SENSOR GROUND CIRCUIT AT PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE TRANS TEMP SIGNAL CIRCUIT SHORTED TO SENSOR GROUND CIRCUIT.*

NO

T E S T S

MEASURE THE RESISTANCE BETWEEN THE TRANS TEMP SIGNAL CIRCUIT...

AT PCM CONNECTOR AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE TRANS TEMP SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

RECONNECT THE TRANSMISSION SOLENOID CONNECTOR.

REMOVE THE TRANS OIL PAN.

DISCONNECT THE TRANS PRESSURE/TEMP SENSOR.** SEE GENERAL INFO 4.2

MEASURE THE RESISTANCE BETWEEN THE TRANS TEMP SIGNAL CIRCUIT AND...

THE SENSOR GROUND CIRCUIT AT PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE TRANSMISSION SOLENOID AND HARNESS ASSEMBLY.*

NO

MEASURE THE RESISTANCE BETWEEN THE TRANS TEMP SIGNAL CIRCUIT...

AT PCM CONNECTOR AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE TRANSMISSION SOLENOID AND HARNESS ASSEMBLY.*

NO

REPLACE THE PRESSURE/TEMPERATURE SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
333

T TEST TC-75A REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO HIGH R O Perform DTC TEST Before Proceeding U AB BODY B L E C O D E T E S T S
FIG. 1
AN BODY BR BODY

FIG. 2
ZJ BODY

FIG. 3

FIG. 4
334

FIG. 5

TEST TC-75A REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO HIGH
Perform DTC TEST Before Proceeding

START TEST TC-75A.

KEY OFF. DISCONNECT ALL PCM CONNECTORS.** SEE GENERAL INFO 4.1

T R O U B L E C O D E

KEY ON. MEASURE THE VOLTAGE AT THE TRANS TEMP SIGNAL CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 1.0 VOLT?

YES

CONTINUE TEST TC-75A ON THE NEXT PAGE.

NO

T E S T S

KEY OFF. MEASURE THE RESISTANCE BETWEEN THE TRANS TEMP SIGNAL CIRCUIT...

AND THE SENSOR GROUND CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 550.0 OHMS?

YES

PERFORM TEST TC-74A.

NO

IS THE RESISTANCE ABOVE 2300.0 OHMS?

YES

PERFORM TEST TC-75B.

NO

RECONNECT ALL CONNECTORS.

WITH THE DRB, READ TRANS TEMP VOLTAGE.

IS THE VOLTAGE ABOVE 3.76 VOLTS?

YES REPLACE THE PCM.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 5

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
335

T TEST TC-75A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO HIGH
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3

FIG. 4

FIG. 5
336

TEST TC-75A CONTINUED - REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO HIGH

TEST TC-75A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE TRANSMISSION SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E T E S T S

MEASURE THE VOLTAGE AT THE TRANS TEMP SIGNAL CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 1.0 VOLT?

YES

REPAIR THE TRANS TEMP SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE.*

NO

RECONNECT THE TRANSMISSION SOLENOID CONNECTOR.

REMOVE THE TRANS OIL PAN AND DISCONNECT THE TRANS PRESSURE /TEMP SENSOR.** SEE GENERAL INFO 4.4

MEASURE THE VOLTAGE AT THE TRANS TEMP SIGNAL CIRCUIT. FIG. 5

IS THE VOLTAGE ABOVE 1.0 VOLT?

YES

REPLACE THE TRANSMISSION SOLENOID AND HARNESS ASSEMBLY.*

NO

REPLACE THE PRESSURE/TEMPERATURE SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
337

T TEST TC-75B REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO HIGH R O Perform TEST TC-75A Before Proceeding U AB BODY AN BODY B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
338

FIG. 4

TEST TC-75B REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO HIGH
Perform TEST TC-75A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-75B.

KEY OFF. DISCONNECT THE TRANS SOLENOID PACK CONNECTOR.**

MEASURE THE RESISTANCE OF THE TRANS TEMP SENSOR SIGNAL CIRCUIT...

FROM THE SOLENOID PACK CONNECTOR TO THE PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.O OHMS

NO

REPAIR THE OPEN TRANS TEMP SENSOR SIGNAL CIRCUIT.*

YES

MEASURE THE RESISTANCE OF THE SENSOR GROUND CIRCUIT...

FROM THE SOLENOID PACK CONNECTOR TO THE PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.O OHMS

NO

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

YES

CONTINUE TEST TC-75A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
339

T TEST TC-75B R O U AB BODY B L E C O D E T E S T S

REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO HIGH
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
340

FIG. 4

TEST TC-75B REPAIRING - TRANS TEMP SENSOR VOLTAGE TOO HIGH

TC-75B CONTINUED FROM THE PREVIOUS PAGE.

T R O U B L E C O D E T E S T S

REMOVE THE TRANS OIL PAN.

DISCONNECT THE TRANS PRESSURE/TEMP SENSOR.** SEE GENERAL INFO 4.4

CONNECT THE TRANS SOLENOID CONNECTOR.

MEASURE THE RESISTANCE OF TRANS TEMP SENSOR SIGNAL CIRCUIT FROM THE PCM CONNECTOR...

TO THE GOVERNOR PRESSURE/TEMP SENSOR CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPLACE THE TRANS SOLENOID/HARNESS ASSEMBLY.*

NO

MEASURE THE RESISTANCE OF SENSOR GROUND CIRCUIT FROM THE PCM CONNECTOR...

TO THE GOVERNOR PRESSURE/TEMP SENSOR CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPLACE THE TRANS SOLENOID/HARNESS ASSEMBLY.*

NO

REPLACE THE TRANS PRESSURE/TEMP SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
341

T TEST TC-76A REPAIRING - IGNITION COIL #4 PRIMARY CIRCUIT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2

FIG. 3
342

FIG. 4

TEST TC-76A REPAIRING - IGNITION COIL #4 PRIMARY CIRCUIT
Perform DTC TEST Before Proceeding

START TEST TC-76A

TURN IGNITION OFF.

T R O U B L E C O D E

DISCONNECT THE SPARK PLUG CABLE AT SPARK PLUG #4. FIG. 1

CONNECT CABLE TO SPARK TESTER. FIG. 2

CONNECT SPARK TESTER TO A GOOD GROUND.

T E S T S

TURN IGNITION ON. (ENGINE OFF)

WITH THE DRB ACTUATE IGNITION COIL #4.

IS THERE GOOD SPARK?

NO

CONTINUE TEST TC-76A ON THE NEXT PAGE.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 3

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WIGGLE WIRING HARNESS FROM THE FRONT COIL PACK TO THE POWERTRAIN CONTROL MODULE.

DOES THE SPARK BECOME ERRATIC OR STOP?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED PROBLEM TO APPEAR.*

NO

REFER TO FIGURE 4 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
343

T TEST TC-76A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - IGNITION COIL #4 PRIMARY CIRCUIT

FIG. 1

FIG. 2

FIG. 3
344

TEST TC-76A CONTINUED - REPAIRING - IGNITION COIL #4 PRIMARY CIRCUIT

TEST TC-76A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE FRONT IGNITION COIL CONNECTOR.** SEE GENERAL INFO 4.0

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED? FIG.1 NO

YES

REPAIR AS NECESSARY.*

T R O U B L E C O D E

KEY ON, WITH THE DRB, ACTUATE IGNITION COIL #4.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

T E S T S

KEY OFF, DISCONNECT POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

USING AN OHMMETER, MEASURE THE IGNITION COIL #4 PRIMARY CIRCUIT TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IGNITION COIL #4 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE IGNITION COIL #4 DRIVER CIRCUIT FROM THE PCM CONNECTOR...

TO THE FRONT IGNITION COIL CONNECTOR. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN IGNITION COIL #4 DRIVER CIRCUIT.*

YES

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE IGNITION COIL #4 PRIMARY CIRCUIT FOR RESISTANCE. FIG. 3

IS THE RESISTANCE BELOW 2.0 OHMS?

NO

REPLACE THE FRONT IGNITION COIL.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
345

T TEST TC-77A REPAIRING - IGNITION COIL #5 PRIMARY CIRCUIT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2

FIG. 3
346

FIG. 4

TEST TC-77A REPAIRING - IGNITION COIL #5 PRIMARY CIRCUIT
Perform DTC TEST Before Proceeding

START TEST TC-77A

TURN IGNITION OFF.

T R O U B L E C O D E

DISCONNECT THE SPARK PLUG CABLE AT SPARK PLUG #5. FIG. 1

CONNECT CABLE TO A SPARK PLUG TESTER. FIG. 2

CONNECT SPARK PLUG TESTER TO A GOOD GROUND.

T E S T S

TURN IGNITION ON. (ENGINE OFF)

WITH THE DRB, ACTUATE IGNITION COIL #5.

IS THERE GOOD SPARK?

NO

CONTINUE TEST TC-77A ON THE NEXT PAGE.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 3

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WIGGLE WIRING HARNESS FROM THE FRONT COIL PACK TO THE POWERTRAIN CONTROL MODULE.

DOES THE SPARK BECOME ERRATIC OR STOP?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED PROBLEM TO APPEAR.*

NO

REFER TO FIGURE 4 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
347

T TEST TC-77A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - IGNITION COIL #5 PRIMARY CIRCUIT

FIG. 1

FIG. 2

FIG. 3
348

TEST TC-77A CONTINUED - REPAIRING - IGNITION COIL #5 PRIMARY CIRCUIT

TEST TC-77A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE FRONT IGNITION COIL CONNECTOR.** SEE GENERAL INFO 4.0

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED? FIG. 1 NO

YES

REPAIR AS NECESSARY.*

T R O U B L E C O D E

KEY ON, WITH THE DRB, ACTUATE IGNITION COIL #5.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

T E S T S

KEY OFF, DISCONNECT POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

USING AN OHMMETER, MEASURE THE IGNITION COIL #5 DRIVER CIRCUIT TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IGNITION COIL #5 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE IGNITION COIL #5 DRIVER CIRCUIT FROM THE PCM CONNECTOR...

TO THE FRONT IGNITION COIL CONNECTOR. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN IGNITION COIL #5 DRIVER CIRCUIT.*

YES

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE IGNITION COIL #5 PRIMARY CIRCUIT FOR RESISTANCE. FIG. 3

IS THE RESISTANCE BELOW 2.0 OHMS?

NO

REPLACE THE FRONT IGNITION COIL.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
349

T TEST TC-79A REPAIRING - INJECTOR #7 CONTROL CIRCUIT R O Perform TEST TC-21A Before Proceeding U B L E C O D E T E S T S
FIG. 1
AB BODY AN BODY

FIG. 2
BR BODY ZJ BODY

FIG. 3

FIG. 4
350

FIG. 5

TEST TC-79A REPAIRING - INJECTOR #7 CONTROL CIRCUIT
Perform TEST TC-21A Before Proceeding

T R O U B L E C O D E T E S T S
NO REPLACE THE FUEL INJECTOR.*

START TEST TC-79A

IS THIS A CNG VEHICLE?

YES

PERFORM TEST TC-79B.

NO

KEY OFF, DISCONNECT THE INJECTOR #7 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE RESISTANCE OF INJECTOR #7. FIG. 1

IS THE RESISTANCE BETWEEN 10.0 AND 16.0 OHMS?

YES

KEY ON, WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2, 3, 4 OR 5

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

CONTINUE TEST TC-79A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
351

T TEST TC-79A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #7 CONTROL CIRCUIT
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
352

FIG. 4

TEST TC-79A CONTINUED - REPAIRING - INJECTOR #7 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-79A CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #7 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #7 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

CONTINUE TEST TC-79A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
353

T TEST TC-79A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - INJECTOR #7 CONTROL CIRCUIT
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
354

FIG. 4

TEST TC-79A CONTINUED - REPAIRING - INJECTOR #7 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-79A CONTINUED FROM PREVIOUS PAGE.

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #7 DRIVER CIRCUIT... FIG. 1, 2, 3 OR 4

FROM THE PCM TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #7 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
355

T TEST TC-79B REPAIRING - INJECTOR #7 CONTROL CIRCUIT R O Perform TEST TC-79A Before Proceeding U AB BODY B L E C O D E T E S T S

FIG. 1
AN BODY BR BODY

FIG. 2

FIG. 3
356

FIG. 4

TEST TC-79B REPAIRING - INJECTOR #7 CONTROL CIRCUIT
Perform TEST TC-79A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-79B

KEY OFF, DISCONNECT THE INJECTOR #7 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #7. FIG. 1

IS THE RESISTANCE BETWEEN 3.0 AND 6.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

KEY ON, WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2, 3 OR 4

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

TEST TC-79B CONTINUED ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
357

T TEST TC-79B R O U AB BODY B L E C O D E T E S T S

CONTINUED - INJECTOR #7 CONTROL CIRCUIT

FIG. 1
AN BODY

FIG. 2
BR BODY

FIG. 3
358

TEST TC-79B CONTINUED - INJECTOR #7 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-79B CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #7 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #7 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #7 DRIVER CIRCUIT... FIG. 1, 2 OR 3

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #7 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
359

T TEST TC-80A REPAIRING - INJECTOR #8 CONTROL CIRCUIT R O Perform TEST TC-21A Before Proceeding U B L E C O D E T E S T S
FIG. 1
AB, AN AND BR BODIES

FIG. 2
ZJ BODY

FIG. 3
360

TEST TC-80A REPAIRING - INJECTOR #8 CONTROL CIRCUIT
Perform TEST TC-21A Before Proceeding

T R O U B L E
YES PERFORM TEST TC-80B.

START TEST TC-80A

IS THIS A CNG FUELED VEHICLE?

NO

C O D E T E S T S

NOTE: ON SOME ENGINES, IT MAY BE NECESSARY TO REMOVE THE INTAKE PLENUM. SEE SERVICE MANUAL.

KEY OFF, DISCONNECT THE INJECTOR #8 CONNECTOR.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #8. FIG. 1

IS THE RESISTANCE BETWEEN 10.0 AND 16.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

KEY ON, WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2 OR 3

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

CONTINUE TEST TC-80A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
361

T TEST TC-80A CONTINUED - REPAIRING - INJECTOR #8 CONTROL CIRCUIT R O U AB, AN AND BR BODIES ZJ BODY B L E C O D E T E S T S

FIG. 1
AB, AN AND BR BODIES ZJ BODY

FIG. 2

FIG. 3
362

FIG. 4

TEST TC-80A CONTINUED - REPAIRING - INJECTOR #8 CONTROL CIRCUIT

T R O U B L E C O D E T E S T S

TEST TC-80A CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #8 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #8 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #8 DRIVER CIRCUIT... FIG. 3 OR 4

FROM THE PCM TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #8 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
363

T TEST TC-80B REPAIRING - INJECTOR #8 CONTROL CIRCUIT R O Perform TEST TC-80A Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2

FIG. 3
364

FIG. 4

TEST TC-80B REPAIRING - INJECTOR #8 CONTROL CIRCUIT
Perform TEST TC-80A Before Proceeding

START TEST TC-80B.

KEY OFF, DISCONNECT THE INJECTOR #8 CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E

USING AN OHMMETER, MEASURE THE RESISTANCE OF INJECTOR #8. FIG. 1

IS THE RESISTANCE BETWEEN 3.0 AND 6.0 OHMS?

NO

REPLACE THE FUEL INJECTOR.*

YES

T E S T S

KEY ON, WITH THE DRB, ACTUATE THE AUTO SHUTDOWN RELAY.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 2

DOES THE VOLTAGE CYCLE HIGH AND LOW?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE INJECTOR #8 DRIVER CIRCUIT IN THE PCM TO GROUND. FIG. 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE INJECTOR #8 DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE ACROSS THE INJECTOR #8 DRIVER CIRCUIT... FIG. 4

FROM THE POWERTRAIN CONTROL MODULE TO THE INJECTOR CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN INJECTOR #8 DRIVER CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
365

T TEST TC-87A REPAIRING - SPEED CONTROL SWITCH ALWAYS LOW R O Perform DTC TEST Before Proceeding U AB, AN AND XJ BODIES B L E C O D E T E S T S

BR BODY

FIG. 1
AB, AN AND XJ BODIES BR BODY

FIG. 2
366

FIG. 3

TEST TC-87A REPAIRING - SPEED CONTROL SWITCH ALWAYS LOW
Perform DTC TEST Before Proceeding

START TEST TC-87A.

RECORD ALL DTC’S AND FREEZE FRAME DATA, NOW ERASE CODES BEFORE PROCEEDING.

IS THIS VEHICLE A "ZJ" BODY?

YES

PERFORM TEST TC-87B

T R O U B L E C O D E

NO

WITH THE DRB, READ THE S/C SWITCH VOLTS IN SENSORS.

IS THE S/C SWITCH VOLTAGE BELOW 1.0 VOLTS? YES

NO

AT THIS TIME THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. SEE GEN INFO 3.3.2

T E S T S

DISCONNECT THE S/C SWITCH.** SEE GENERAL INFO 4.7

DID THE S/C SWITCH VOLTS CHANGE TO 5.0 VOLTS? NO

YES

REPLACE THE S/C SWITCH.*

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE S/C SIGNAL CIRCUIT...

AND THE SENSOR GROUND CIRCUIT. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR S/C SIGNAL CIRCUIT SHORTED TO SENSOR GROUND.*

NO

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

WITH AN OHMMETER, MEASURE RESISTANCE OF S/C SWITCH SIGNAL CKT TO GND AT THE PCM. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR S/C SWITCH SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
367

T TEST TC-87B REPAIRING - SPEED CONTROL SWITCH ALWAYS LOW R O Perform TEST TC-87A Before Proceeding U B L E C O D E T E S T S

ZJ BODY

ZJ BODY

FIG. 1
368

TEST TC-87B REPAIRING - SPEED CONTROL SWITCH ALWAYS LOW
Perform TEST TC-87A Before Proceeding

START TEST TC-87B.

WITH THE DRB, READ THE S/C SWITCH VOLTS IN SENSORS.

IS THE S/C SWITCH VOLTAGE BELOW 1.0 VOLTS? YES

NO

AT THIS TIME THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT SEE GEN INFO 3.3.2

T R O U B L E C O D E

DISCONNECT THE S/C ON/OFF SWITCH.** SEE GENERAL INFO 4.7

DID THE S/C SWITCH VOLTS CHANGE TO 5.0 VOLTS? NO

YES

REPLACE THE S/C ON/OFF SWITCH.*

T E S T S

DISCONNECT THE S/C CANCEL SWITCH.** SEE GENERAL INFO 4.7

DID THE S/C SWITCH VOLTS CHANGE TO 5.0 VOLTS? NO

YES

REPLACE THE S/C CANCEL SWITCH.*

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE S/C SIGNAL CIRCUIT...

AND THE SENSOR GROUND CIRCUIT. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR S/C SIGNAL CIRCUIT SHORTED TO SENSOR GROUND.*

NO

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

WITH AN OHMMETER, MEASURE RESISTANCE OF THE S/C SWITCH SIGNAL CIRCUIT...

TO GROUND AT THE PCM. IS THE RESISTANCE BELOW 5.0 OHMS? FIG. 1 YES

NO

REPLACE THE POWER TRAIN CONTROL MODULE.*

REPAIR S/C SWITCH SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
369

T TEST TC-94A REPAIRING - CNG TEMP SENSOR VOLTAGE TOO LOW R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
370

TEST TC-94A REPAIRING - CNG TEMP SENSOR VOLTAGE TOO LOW
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-94A.

WITH THE DRB, READ THE FUEL TEMPERATURE SENSOR VOLTAGE.

YES IS THE FUEL TEMP SENSOR VOLTAGE BELOW 0.29 VOLTS? CONTINUE TEST TC-94A ON THE NEXT PAGE.

NO

WIGGLE THE FUEL TEMP SENSOR CONNECTOR AND HARNESS WIRES.

YES MONITOR THE DRB DISPLAY. WAS THERE ANY FUEL TEMP SENSOR VOLTAGE CHANGE?

REPAIR THE CONNECTOR OR HARNESS WIRES THAT CAUSED THE VOLTAGE CHANGE.*

NO

AT THIS TIME THE CONDITION REQUIRED TO SET THIS CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

YES WERE ANY PROBLEMS FOUND? REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
371

T TEST TC-94A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - CNG TEMP SENSOR VOLTAGE TOO LOW

FIG. 1

372

TEST TC-94A CONTINUED - REPAIRING - CNG TEMP SENSOR VOLTAGE TOO LOW

TEST TC-94A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE FUEL TEMP SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

T R O U B L E C O D E T E S T S

WITH THE DRB, MONITOR THE FUEL TEMPERATURE SENSOR VOLTAGE.

YES IS THE FUEL TEMP SENSOR VOLTAGE ABOVE 4.0 VOLTS?

RELEASE THE FUEL PRESSURE. SEE GENERAL INFO 9.1 REPLACE THE FUEL TEMP SENSOR.*

NO

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE FUEL TEMP SENSOR SIGNAL CIRCUIT TO GROUND. FIG. 1

YES IS THE RESISTANCE BELOW 5.0 OHMS?

REPAIR THE FUEL TEMP SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE SENSOR SIGNAL..

CIRCUIT TO THE SENSOR GROUND CIRCUIT. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE FUEL TEMP SENSOR SHORT TO SENSOR GROUND.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
373

T TEST TC-95A REPAIRING - CNG TEMP SENSOR VOLTAGE TOO HIGH R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
374

TEST TC-95A REPAIRING - CNG TEMP SENSOR VOLTAGE TOO HIGH
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-95A.

WITH THE DRB, READ THE FUEL TEMPERATURE SENSOR VOLTAGE.

YES IS THE FUEL TEMP SENSOR VOLTAGE ABOVE 4.6 VOLTS? CONTINUE TEST TC-95A ON THE NEXT PAGE.

NO

WIGGLE THE FUEL TEMP SENSOR CONNECTOR AND HARNESS WIRES.

YES MONITOR THE DRB DISPLAY. WAS THERE ANY FUEL TEMP SENSOR VOLTAGE CHANGE?

REPAIR THE CONNECTOR OR HARNESS WIRES THAT CAUSED THE VOLTAGE CHANGE.*

NO

AT THIS TIME THE CONDITION REQUIRED TO SET THIS CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

YES WERE ANY PROBLEMS FOUND? REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
375

T TEST TC-95A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - CNG TEMP SENSOR VOLTAGE TOO HIGH

FIG. 1

FIG. 2
376

TEST TC-95A CONTINUED - REPAIRING - CNG TEMP SENSOR VOLTAGE TOO HIGH

TEST TC-95A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE FUEL TEMP SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

T R O U B L E C O D E

WITH A VOLTMETER, MEASURE THE FUEL TEMP SENSOR CIRCUIT... FIG. 1

AT THE FUEL TEMP SENSOR CONNECTOR.

IS THE VOLTAGE ABOVE 6.0 VOLTS?

YES

REPAIR THE FUEL TEMP SENSOR CIRCUIT SHORTED TO VOLTAGE.*

NO

T E S T S

CONNECT A JUMPER WIRE ACROSS THE SENSOR SIGNAL AND SENSOR GROUND CKTS. FIG. 1

WITH THE DRB , MONITOR THE FUEL TEMP SENSOR VOLTAGE.

IS THE FUEL TEMP SENSOR VOLTAGE BELOW 1.0 VOLT?

YES

RELEASE THE FUEL PRESSURE. SEE GENERAL INFO 9.1 REPLACE THE FUEL TEMP SENSOR.*

NO

MOVE THE JUMPER WIRE FROM THE SENSOR GROUND TO AN ENGINE GROUND. FIG. 1

WITH THE DRB, MONITOR THE FUEL TEMP SENSOR VOLTAGE.

IS THE FUEL TEMP SENSOR VOLTAGE BELOW 1.0 VOLT?

YES

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

NO

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

WITH AN OHMMETER, MEASURE THE FUEL TEMP SENSOR SIGNAL CIRCUIT FROM PCM TO CONN. FIG. 2

NO IS THE RESISTANCE BELOW 5.0 OHMS? REPAIR THE OPEN FUEL TEMP SENSOR SIGNAL CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
377

T TEST TC-98A REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO HIGH R O Perform DTC TEST Before Proceeding U AN AND BR BODIES AB BODY B L E C O D E T E S T S

FIG. 1
378

FIG. 2

TEST TC-98A REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO HIGH
Perform DTC TEST Before Proceeding

START TEST TC-98A.

WITH THE DRB, ERASE CODES.

IGNITION KEY OFF FOR TEN SECOUNDS.

T R O U B L E C O D E

ATTEMPT TO START THE ENGINE AND LET IDLE.

WITH THE DRB, READ CODES.

DID THE "CNG PRESSURE SENSOR VOLTAGE TOO HIGH" CODE RETURN?

YES

CONTINUE TEST TC-98A ON THE NEXT PAGE.

NO

T E S T S

WIGGLE THE FUEL PRESSURE SENSOR CONNECTORS AND HARNESS. SEE GENERAL INFO 4.0

WITH THE DRB, MONITOR THE FUEL PRESSURE SENSOR VOLTAGE WHILE WIGGLING.

WAS THERE ANY CHANGE IN FUEL PRESSURE SENSOR VOLTAGE WHEN WIGGLED? NO

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

WITH THE DRB, READ CODES.

DID THE "CNG PRESSURE SENSOR VOLTAGE TOO HIGH" CODE RETURN?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE CODE TO RETURN.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
379

T TEST TC-98A CONTINUED - REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO HIGH R O U AN AND BR BODIES AB BODY B L E C O D E T E S T S

FIG. 1
AN AND BR BODIES AB BODY

FIG. 2

FIG. 3
380

FIG. 4

TEST TC-98A CONTINUED - REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO HIGH

TEST TC-98A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE CNG FUEL PRESSURE SENSOR CONNECTOR.** SEE GENERAL INFO 4.0

T R O U B L E C O D E

USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE CNG FUEL PRESSURE SENSOR SIGNAL CIRCUIT. FIG. 1 OR 2

IS THE VOLTAGE ABOVE 4.0 VOLTS?

YES

REPAIR THE FUEL PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE.*

NO

T E S T S

USE AN OHMMETER IN THE FOLLOWING STEP.

KEY OFF, MEASURE THE CNG FUEL PRESSURE SENSOR GROUND CIRCUIT. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

YES

TURN IGNITION OFF.

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE CNG FUEL PRESSURE SENSOR SIGNAL CIRCUIT FOR RESISTANCE. FIG. 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN FUEL PRESSURE SIGNAL CIRCUIT.*

YES

CONTINUE TEST TC-98A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
381

T TEST TC-98A CONTINUED - REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO HIGH R O U AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
AB BODY

FIG. 2
382

TEST TC-98A CONTINUED - REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO HIGH

TEST TC-98A CONTINUED FROM THE PREVIOUS PAGE.

RECONNECT ALL PREVIOUSLY DISCONNECTED CONNNECTORS.

T R O U B L E C O D E T E S T S

TURN IGNITION KEY ON.

DISCONNECT THE FUEL PRESSURE SENSOR.** SEE GENERAL INFO 4.4

WITH THE DRB, READ THE CNG FUEL PRESSURE SENSOR PRESSURE AND NOTE PRESSURE READING.

JUMPER THE CNG FUEL PRESSURE SIGNAL CIRCUIT TO THE SENSOR GROUND CIRCUIT. FIG. 1 OR 2

WITH THE DRB, READ THE CNG FUEL PRESSURE SENSOR PRESSURE.

DID THE CNG FUEL PRESSURE SENSOR PRESSURE DROP TO 0 WHEN JUMPERED?

YES

NOTE: SEE GENERAL INFO 9.0 FOR FUEL RELEASE PROCEDURE.

NO

REPLACE THE FUEL PRESSURE SENSOR.*

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
383

T TEST TC-99A REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO LOW R O Perform DTC TEST Before Proceeding U AN AND BR BODIES AB BODY B L E C O D E T E S T S

FIG. 1
384

FIG. 2

TEST TC-99A REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO LOW
Perform DTC TEST Before Proceeding

START TEST TC-99A.

WITH THE DRB, ERASE CODES.

IGNITION KEY OFF FOR TEN SECOUNDS.

T R O U B L E C O D E

ATTEMPT TO START THE ENGINE AND LET IDLE.

WITH THE DRB, READ CODES.

DID THE "CNG PRESSURE SENSOR VOLTAGE TOO LOW" CODE RETURN?

YES

CONTINUE TEST TC-99A ON THE NEXT PAGE.

NO

T E S T S

WIGGLE THE FUEL PRESSURE SENSOR CONNECTORS AND HARNESS. SEE GENERAL INFO 4.0

WITH THE DRB, MONITOR THE FUEL PRESSURE SENSOR VOLTAGE WHILE WIGGLING HARNESS.

DID WIGGLING CAUSE THE FUEL PRESSURE SENSOR VOLTAGE TO CHANGE?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

NO

WITH THE DRB, READ CODES.

DID THE "CNG PRESSURE SENSOR VOLTAGE TOO LOW" CODE RETURN?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE CODE TO RETURN.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
385

T TEST TC-99A CONTINUED - REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO LOW R O U AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
AB BODY

FIG. 2
386

TEST TC-99A CONTINUED - REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO LOW

TEST TC-99A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE FUEL PRESSURE SENSOR CONNNECTOR.** SEE GENERAL INFO 4.4

T R O U B L E C O D E

USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE CNG PRESSURE SENSOR 5-VOLT SUPPLY CIRCUIT. FIG. 1 OR 2

IS THE VOLTAGE ABOVE 4.0 VOLTS?

NO

REPAIR THE OPEN FUEL PRESSURE SENSOR 5-VOLT SUPPLY CIRCUIT.*

YES

T E S T S

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE BETWEEN THE FUEL PRESSURE SENSOR SIGNAL CIRCUIT AND THE GROUND CIRCUIT. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE FUEL PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO SENSOR GROUND CIRCUIT.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE FUEL PRESSURE SENSOR SIGNAL CIRCUIT TO GROUND. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE FUEL PRESSURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

CONTINUE TEST TC-99A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
387

T TEST TC-99A CONTINUED - REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO LOW R O U AN AND BR BODIES B L E C O D E T E S T S

FIG. 1
AB BODY

FIG. 2
388

TEST TC-99A CONTINUED - REPAIRING - CNG PRESSURE SENSOR VOLTAGE TOO LOW

TEST TC-99A CONTINUED FROM THE PREVIOUS PAGE.

RECONNECT ALL PREVIOUSLY DISCONNECTED CONNNECTORS.

T R O U B L E C O D E T E S T S

TURN IGNITION KEY ON.

DISCONNECT THE FUEL PRESSURE SENSOR.** SEE GENERAL INFO 4.4

WITH THE DRB, READ THE FUEL PRESSURE SENSOR VOLTAGE.

IS THE FUEL PRESSURE SENSOR VOLTAGE ABOVE 4.0 VOLTS?

YES

NOTE: SEE GENERAL INFO 9.0 FOR FUEL RELEASE PROCEDURE.

NO

REPLACE THE FUEL PRESSURE SENSOR.*

REPLACE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
389

T TEST TC-101A REPAIRING - FUEL PUMP (SYSTEM) RELAY CONTROL CIRCUIT R O Perform DTC TEST Before Proceeding U AB BODY AN AND BR BODIES B L E C O D E T E S T S

XJ BODY

ZJ BODY

FIG. 1
390

FIG. 2

TEST TC-101A REPAIRING - FUEL PUMP (SYSTEM) RELAY CONTROL CIRCUIT
Perform DTC TEST Before Proceeding

T R O U B L E
PERFORM TEST TC-101B.

START TEST TC-101A.

IS THE VEHICLE EQUIPPED WITH CNG?

YES

NO

C O D E T E S T S

WITH THE DRB, ACTUATE THE FUEL PUMP RELAY. SEE GENERAL INFO 4.6

IS THE FUEL PUMP RELAY CLICKING?

NO

CONTINUE TEST TC-101A ON THE NEXT PAGE.

YES

THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH THE DRB, ACTUATE THE FUEL PUMP RELAY. SEE GENERAL INFO 4.6

WIGGLE THE WIRING HARNESS FROM THE RELAY TO THE POWERTRAIN CONTROL MODULE.

DID THE RELAY CLICKING STOP OR BECOME IRREGULAR WHEN WIGGLING THE WIRES? NO

YES

REPAIR CIRCUIT AS NECESSARY WHERE WIGGLING CAUSED THE CLICKING TO STOP OR BECOME IRREGULAR.*

REFER TO FIGURE 2 FOR INACTIVE TROUBLE CODE CONDITION INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
391

T TEST TC-101A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - FUEL PUMP (SYSTEM) RELAY CONTROL CIRCUIT
AN BODY

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
392

FIG. 6

TEST TC-101A CONTINUED - REPAIRING - FUEL PUMP (SYSTEM) RELAY CONTROL CIRCUIT

TEST TC-101A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE FUEL PUMP RELAY.** SEE GENERAL INFO 4.6

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CKT AT RELAY. FIG. 1, 2, 3, 4 OR 5

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGN SWITCH OUTPUT CIRCUIT.*

YES

T E S T S

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE RESISTANCE BETWEEN TERMINALS 85 AND 86 OF THE FUEL SYSTEM RELAY. FIG. 6

IS THE RESISTANCE BELOW 100.0 OHMS?

NO

REPLACE FUEL PUMP RELAY.*

YES

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE GREY CONNECTOR.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE FUEL PUMP RELAY CONTROL CKT AT PCM TO GND. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE FUEL PUMP RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE FUEL SYSTEM RELAY CONTROL CIRCUIT...

FROM THE PCM TO THE RELAY. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR OPEN FUEL PUMP RELAY CONTROL CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
393

T TEST TC-101B REPAIRING - FUEL PUMP (SYSTEM) RELAY CONTROL CIRCUIT R O Perform TEST TC-101A Before Proceeding U AB BODY B L E C O D E T E S T S

AN BODY

BR BODY

FIG. 1
394

FIG. 2

TEST TC-101B REPAIRING - FUEL PUMP (SYSTEM) RELAY CONTROL CIRCUIT
Perform TEST TC-101A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-101B.

WITH THE DRB, ACTUATE THE HI PRESSURE FUEL SHUTOFF RELAY. SEE GENERAL INFO 4.6

IS THE RELAY CLICKING?

NO

CONTINUE TEST TC-101B ON THE NEXT PAGE.

YES

THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH THE DRB, ACTUATE THE HI PRESSURE FUEL SHUTOFF RELAY. SEE GENERAL INFO 4.6

WIGGLE THE WIRING HARNESS FROM THE RELAY TO THE POWERTRAIN CONTROL MODULE.

DID THE RELAY CLICKING STOP OR BECOME IRREGULAR WHILE WIGGLING THE WIRES? NO

YES

REPAIR CIRCUIT AS NECESSARY WHERE WIGGLING CAUSED THE CLICKING TO STOP OR BECOME IRREGULAR.

REFER TO FIGURE 2 FOR INACTIVE TROUBLE CODE CONDITION INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
395

T TEST TC-101B R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - FUEL PUMP (SYSTEM) RELAY CONTROL CIRCUIT
AN BODY

FIG. 1
BR BODY

FIG. 2

FIG. 3
396

FIG. 4

TEST TC-101B CONTINUED - REPAIRING - FUEL PUMP (SYSTEM) RELAY CONTROL CIRCUIT

TEST TC-101B CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE FUEL SYSTEM RELAY.** SEE GENERAL INFO 4.6

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CKT AT RELAY. FIG. 1, 2 OR 3

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGN SWITCH OUTPUT CIRCUIT.*

YES

T E S T S

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE RESISTANCE BETWEEN TERMINALS 85 & 86 OF THE FUEL SYSTEM RLY. FIG. 4

IS THE RESISTANCE BELOW 100.0 OHMS?

NO

REPLACE FUEL SYSTEM RELAY.*

YES

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE GREY CONNECTOR.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE FUEL SYSTEM RELAY CONTROL CKT AT PCM TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE FUEL SYSTEM RELAY CONTROL CKT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE FUEL SYSTEM RELAY CONTROL CIRCUIT...

FROM THE PCM TO THE RELAY. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR OPEN FUEL SYSTEM RELAY CONTROL CKT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
397

T TEST TC-102A REPAIRING - 1/1 O2 SENSOR SLOW RESPONSE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1
TYPICAL CONNECTOR

FIG. 2
398

TEST TC-102A REPAIRING - 1/1 O2 SENSOR SLOW RESPONSE
Perform DTC TEST Before Proceeding

START TEST TC-102A.

REFER TO FIGURE 1 FOR POSSIBLE TROUBLE CODE CAUSES.

T R O U B L E C O D E

START THE ENGINE.

CHECK THE EXHAUST SYSTEM FOR LEAKS BETWEEN THE ENGINE AND THE CATALYST.

IS THERE ANY EXHAUST LEAK?

YES

REPAIR OR REPLACE LEAKING EXHAUST PARTS AS NECESSARY.*

NO

T E S T S

NOTE: CHECK THE EXHAUST FOR EXCESSIVE SMOKE CAUSED BY OIL OR COOLANT CONSUMPTION.

IS THERE AN OIL OR COOLANT CONSUMPTION CONDITION PRESENT?

YES

REPAIR ENGINE MECHANICAL AS NECESSARY AND REPLACE THE 1/1 O2 SENSOR.*

NO

TURN IGNITION OFF. DISCONNECT THE 1/1 O2 SENSOR.** SEE GENERAL INFO 4.4

INSPECT THE CONNECTORS AND TERMINALS.

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE 1/1 O2 SENSOR GROUND CIRCUIT FROM...

THE 1/1 O2 SENSOR CONNECTOR TO GROUND. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN 1/1 O2 SENSOR GROUND CIRCUIT.*

YES

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

INSPECT THE CONNECTORS AND TERMINALS.

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

REPLACE THE 1/1 O2 SENSOR.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
399

T TEST TC-103A REPAIRING - 1/1 O2 SENSOR HEATER FAILURE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

400

TEST TC-103A REPAIRING - 1/1 O2 SENSOR HEATER FAILURE
Perform DTC TEST Before Proceeding

START TEST TC-103A.

WITH THE DRB, READ ALL TROUBLE CODES.

ARE THERE ANY OTHER "1/1 O2 SENSOR" RELATED TROUBLE CODES?

YES

REFER TO "DTC TEST" TO PERFORM THE APPROPRIATE OXYGEN SENSOR TEST.

T R O U B L E C O D E T E S T S

NO

TURN IGNITION ON (ENGINE OFF).

WAIT 3 MINUTES.

WITH THE DRB IN SENSORS, MONITOR THE 1/1 O2 SENSOR VOLTAGE.

WAIT FOR THE VOLTAGE READING TO STABILIZE ABOVE 4.5 VOLTS.

WITH THE DRB IN ACTUATOR TESTS, PERFORM THE O2 SENSOR HEATER TEST.

MONITOR THE 1/1 O2 SENSOR VOLTAGE FOR THREE MINUTES.

IS THE 1/1 O2 SENSOR VOLTAGE STILL ABOVE 1.0 VOLT?

YES

CONTINUE TEST TC-103A ON THE NEXT PAGE.

NO

DID YOU COME FROM TEST TC-118A?

YES

CONTINUE TEST TC-118A.

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

STOP ALL ACTUATOR TESTS. TEST COMPLETE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
401

T TEST TC-103A CONTINUED - REPAIRING - 1/1 O2 SENSOR HEATER FAILURE R O U TYPICAL CONNECTOR B L E C O D E T E S T S

FIG. 1
TYPICAL CONNECTOR

FIG. 2
402

TEST TC-103A CONTINUED - REPAIRING - 1/1 O2 SENSOR HEATER FAILURE

TEST TC-103A CONTINUED FROM THE PREVIOUS PAGE

DISCONNECT THE 1/1 O2 SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

T R O U B L E C O D E T E S T S

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

NOTE: THE DRB IS STILL ACTUATING THE O2 SENSOR HEATER TEST.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

STOP ALL ACTUATOR TESTS.

USING AN OHMMETER, MEASURE THE O2 SENSOR HEATER ELEMENT. FIG. 2

IS THE RESISTANCE BETWEEN 4.0 AND 7.0 OHMS?

NO

REPLACE THE 1/1 O2 SENSOR.*

YES

USING AN OHMMETER, MEASURE FROM THE HEATER GROUND...

CIRCUIT TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN 1/1 O2 SENSOR GROUND CIRCUIT.*

YES

REPLACE THE 1/1 O2 SENSOR.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
403

T TEST TC-104A REPAIRING - 1/2 O2 SENSOR SLOW RESPONSE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
404

TEST TC-104A REPAIRING - 1/2 O2 SENSOR SLOW RESPONSE
Perform DTC TEST Before Proceeding

START TEST TC-104A.

REFER TO FIGURE 1 FOR POSSIBLE TROUBLE CODE CAUSES.

T R O U B L E C O D E

START THE ENGINE.

CHECK THE EXHAUST SYSTEM FOR LEAKS BETWEEN THE ENGINE AND THE CATALYST.

IS THERE ANY EXHAUST LEAK?

YES

REPAIR OR REPLACE LEAKING EXHAUST PARTS AS NECESSARY.*

NO

T E S T S

NOTE: CHECK THE EXHAUST FOR EXCESSIVE SMOKE CAUSED BY OIL OR COOLANT CONSUMPTION.

IS THERE AN OIL OR COOLANT CONSUMPTION CONDITION PRESENT?

YES

REPAIR ENGINE MECHANICAL AS NECESSARY AND REPLACE THE 1/2 O2 SENSOR.*

NO

TURN IGNITION OFF. DISCONNECT THE 1/2 O2 SENSOR.** SEE GENERAL INFO 4.4

INSPECT THE CONNECTORS AND TERMINALS.

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE 1/2 O2 SENSOR GROUND CIRCUIT FROM...

THE 1/2 O2 SENSOR CONNECTOR TO GROUND. FIG. 2

IS THE RESISTEANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN 1/2 O2 SENSOR GROUND CIRCUIT.*

YES

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

INSPECT THE CONNECTORS AND TERMINALS.

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

REPLACE THE 1/2 O2 SENSOR.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
405

T TEST TC-105A REPAIRING - 1/2 O2 SENSOR HEATER FAILURE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1
8.0L CAL/MD ALL OTHERS

406

TEST TC-105A REPAIRING - 1/2 O2 SENSOR HEATER FAILURE
Perform DTC TEST Before Proceeding

START TEST TC-105A.

WITH THE DRB, READ ALL TROUBLE CODES.

ARE THERE ANY OTHER "1/2 O2 SENSOR" RELATED TROUBLE CODES?

YES

REFER TO "DTC TEST" TO PERFORM THE APPROPRIATE OXYGEN SENSOR TEST.

T R O U B L E C O D E T E S T S

NO

TURN IGNITION ON (ENGINE OFF).

WAIT 3 MINUTES.

WITH THE DRB IN SENSORS, MONITOR THE 1/2 O2 SENSOR VOLTAGE.

WAIT FOR THE VOLTAGE READING TO STABILIZE ABOVE 4.5 VOLTS.

WITH THE DRB IN ACTUATOR TESTS, PERFORM THE O2 SENSOR HEATER TEST.

MONITOR THE 1/2 O2 SENSOR VOLTAGE FOR THREE MINUTES.

IS THE 1/2 O2 SENSOR VOLTAGE ABOVE 1.0 VOLT?

YES

CONTINUE TEST TC-105A ON THE NEXT PAGE.

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

STOP ALL ACTUATOR TESTS. TEST COMPLETE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
407

T TEST TC-105A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 1/2 O2 SENSOR HEATER FAILURE

FIG. 1

FIG. 2
408

TEST TC-105A CONTINUED - REPAIRING - 1/2 O2 SENSOR HEATER FAILURE

TEST TC-105A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE 1/2 O2 SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

T R O U B L E C O D E T E S T S

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

NOTE: THE DRB IS STILL ACTUATING THE O2 SENSOR HEATER TEST.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

STOP ALL ACTUATOR TESTS.

USING AN OHMMETER, MEASURE THE O2 SENSOR HEATER ELEMENT. FIG. 2

IS THE RESISTANCE BETWEEN 4.0 AND 7.0 OHMS?

NO

REPLACE THE 1/2 O2 SENSOR.*

YES

USING AN OHMMETER, MEASURE FROM THE HEATER GROUND...

CIRCUIT TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN 1/2 O2 SENSOR GROUND CIRCUIT.*

YES

REPLACE THE 1/2 O2 SENSOR.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
409

T TEST TC-106A REPAIRING - MULTIPLE CYLINDER MIS-FIRE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
410

TEST TC-106A REPAIRING - MULTIPLE CYLINDER MIS-FIRE
Perform DTC TEST Before Proceeding

START TEST TC-106A.

NOTE: YOU MUST REPAIR ANY NON-MISFIRE TROUBLE CODES BEFORE CONTINUING.

THIS CODE WILL ONLY SET IF THE CONDITION OCCURS DURING THE ROAD TEST.

WITH THE DRB, ERASE TROUBLE CODES.

T R O U B L E C O D E

NOTE: IN THE NEXT STEP, YOU MUST STOP IN THE MIDDLE OF YOUR ROAD TEST, KEY OFF, THEN BACK ON...

THE ENGINE MUST BE AT OPERATING TEMPERATURE AND ADAPTIVE NUMERATOR UPDATED.

DRIVE VEHICLE AT A STEADY RATE AT VARIOUS MAP AND RPM RANGES...

NOTE: SHARP MANEUVERS MAY TEMPORARILY DISABLE MISFIRE DETECTION.

T E S T S

TEST DRIVE VEHICLE.

WITH THE DRB, READ TROUBLE CODES.

DID THE "MULTIPLE CYLINDER MISFIRE" TROUBLE CODE RETURN?

YES

CONTINUE TEST TC-106A ON THE NEXT PAGE.

NO

IS ANY SINGLE CYLINDER MISFIRE TROUBLE CODE PRESENT?

YES

PERFORM TEST TC-107A.

NO

CONNECT A SUITABLE ENGINE ANALYZER TO THE ENGINE AND START ENGINE.

FOLLOW THE EQUIPMENT MANUFACTURER’S PROCEDURE FOR PATTERN ANALYSIS. FIG. 1

IS THE SECONDARY IGNITION PATTERN OK?

NO

REPAIR OR REPLACE THE FAILED COMPONENT IN THE SECONDARY IGNITION SYSTEM.*

YES

NOTE: DO NOT SPRAY INDUCTIVE PICKUP.

WITH A SPRAY BOTTLE SPRAY IGNITION CABLES WITH WATER AND MONITOR IGNITION PATTERN.

DID IGNITION PATTERN CHANGE?

YES

REPAIR THE INDICATED COMPONENT IN THE SECONDARY IGNITION SYSTEM.*

NO

NOTE: AN INACURRATE SPEED SENSOR READING (TOO HIGH) MAY CAUSE THIS CODE TO SET INTERMITTENTLY.

AT THIS TIME, THE CONDITIONS REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 2

REFER TO GEN INFO 3.3.2 FOR ADDITIONAL INFORMATION ON INACTIVE TROUBLE CODES.*

TEST COMPLETE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
411

T TEST TC-106A R O U 2.5L ENGINES B L E C O D E T E S T S

CONTINUED - REPAIRING - MULTIPLE CYLINDER MIS-FIRE
4.0L ENGINES

FIG. 1
3.9L ENGINES

FIG. 2
5.2L AND 5.9L ENGINES

FIG. 3
412

FIG. 4

TEST TC-106A CONTINUED - REPAIRING - MULTIPLE CYLINDER MIS-FIRE

TEST TC-106A CONTINUED FROM THE PREVIOUS PAGE.

INSPECT IGNITION CABLES FOR PROPER LOCATION. FIG. 1, 2, 3 OR 4

T R O U B L E
REPAIR AS NECESSARY.*

ARE THE IGNITION CABLES INSTALLED CORRECTLY?

NO

YES

C O D E T E S T S

TURN IGNITION OFF. CONNECT A SUITABLE ENGINE ANALYZER,THEN START ENGINE AND LET IDLE FOR 2 MINUTES.

FOLLOW THE EQUIPMENT MANUFACTURER’S PROCEDURE FOR PATTERN ANALYSIS.

IS THE SECONDARY IGNITION PATTERN OK?

NO

REPAIR THE FAULTY COMPONENT(S) IN THE SECONDARY IGNITION SYSTEM.*

YES

MOMENTARILY REMOVE & REINSTALL SPARK PLUG WIRES FROM IGNITION COIL OR DISTRIBUTOR ONE AT A TIME.

WHILE DISCONNECTING EACH WIRE, OBSERVE THE SECONDARY KV PEAK LINE.

IS THE OPEN CIRCUIT SECONDARY VOLTAGE AT LEAST 25KV FOR EACH WIRE? YES

NO

REPLACE THE IGNITION COIL.*

TURN ENGINE OFF. REMOVE ALL SPARK PLUGS & ASD RELAY.

USING APPROPRIATE PRESSURE GAUGE, TEST ALL CYLINDERS FOR PROPER COMPRESSION.

DO ALL CYLINDERS HAVE A MINIMUM COMPRESSION OF 100 PSI AND WITHIN 25% OF EACH OTHER? YES

NO

REPAIR ENGINE MECHANICAL PROBLEM AS NECESSARY.*

REINSTALL ALL SPARK PLUGS, WIRES AND ASD RELAY.

CONTINUE TEST TC-106A ON THE NEXT PAGE.

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
413

T TEST TC-106A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - MULTIPLE CYLINDER MIS-FIRE

FIG. 1

414

TEST TC-106A CONTINUED - REPAIRING - MULTIPLE CYLINDER MIS-FIRE

TEST TC-106A CONTINUED FROM THE PREVIOUS PAGE.

TURN IGNITION OFF.

CONNECT A VACUUM GAUGE TO ENGINE VACUUM.

T R O U B L E C O D E

RUN ENGINE UNTIL NORMAL OPERATING TEMPERATURE IS REACHED. (180 DEGREES F)

DEPRESS PARKING BRAKE AND PUT SHIFT LEVER IN THE NEUTRAL POSITION. READ VACUUM GAUGE.

DOES THE VACUUM GAUGE READ AT LEAST 13 INCHES. OF VACUUM? FIG. 1 YES

NO

PERFORM TEST NTC-22A.

T E S T S

WHILE MONITORING THE VACUUM GAUGE, SNAP THE THROTTLE OPEN AND CLOSED.

DID THE VACUUM DROP RAPIDLY TO ZERO?

NO

REPAIR RESTRICTED EXHAUST SYSTEM.*

YES

TURN IGNITION OFF.

WARNING: THE FUEL SYSTEM MUST BE OPENED AND MAY BE UNDER PRESSURE. SEE GENERAL INFO 9.1

CONNECT A FUEL PRESSURE GAUGE TO THE FUEL RAIL. SEE APPROPRIATE SERVICE MANUAL.

TURN IGNITION ON. WITH THE DRB, ACTUATE THE FUEL SYSTEM TEST.

ALLOW TIME FOR FUEL PRESSURE GAUGE TO STABILIZE TO NORMAL FUEL PRESSURE.

WITH THE DRB, STOP FUEL SYSTEM TEST. MONITOR THE FUEL PRESSURE GAUGE FOR 1 MINUTE.

IS THE FUEL PRESSURE BELOW 45 PSI?

YES

PERFORM TEST NTC-3A.

NO

INSPECT THE AIR FILTER AND INLET DUCTS FOR RESTRICTIONS.

WERE THERE ANY RESTRICTIONS?

YES

CLEAN THE RESTRICTED AIR INLET SYSTEM AS NECESSARY.*

NO

NOTE: AN INACCURATE SPEED SENSOR READING (TOO HIGH) MAY CAUSE THIS CODE TO SET INTERMITTENTLY.

CONTINUE TEST TC-106A ON THE NEXT PAGE.

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
415

T TEST TC-106A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - MULTIPLE CYLINDER MIS-FIRE

NOTES

416

TEST TC-106A CONTINUED − REPAIRING − MULTIPLE CYLINDER MIS-FIRE
Make sure all the wiring and connectors are ok. Perform each of the following tests in the order listed below. If a test passes, continue to the next test until the problem is found: Secondary Ignition Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-2A Fuel Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-3A PCM Grounds and Power Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-11A EGR System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-13A Engine Mechanical Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-22A

T R O U B L E C O D E T E S T S

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
417

T TEST TC-107A REPAIRING - CYLINDER #1, #2, #3, #4, #5, #6, #7, OR #8 MISFIRE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S
FIG. 1
2.5L ENGINES 4.0L ENGINES

FIG. 2
3.9L ENGINES 5.2L 5.9L ENGINES

FIG. 3

FIG. 4
418

FIG. 5

TEST TC-107A REPAIRING - CYLINDER #1, #2, #3, #4, #5, #6, #7, OR #8 MISFIRE
Perform DTC TEST Before Proceeding

START TEST TC-107A.

NOTE: YOU MUST REPAIR MULTIPLE MISFIRE OR ANY NON-MISFIRE TROUBLE CODES FIRST.

T R O U B L E C O D E

NOTE: READ FIGURE 1 TO GET A CLEAR UNDERSTANDING OF THIS CODE BEFORE PROCEEDING.

INSPECT IGNITION CABLES FOR PROPER LOCATION. FIG. 2, 3, 4 OR 5

ARE THE IGNITION CABLES INSTALLED CORRECTLY?

NO

REPAIR AS NECESSARY.*

YES

T E S T S

TURN IGNITION OFF. CONNECT A SUITABLE ENGINE ANALYZER,THEN START ENGINE AND LET IDLE FOR 2 MINUTES.

FOLLOW THE EQUIPMENT MANUFACTURER’S PROCEDURE FOR PATTERN ANALYSIS.

IS THE SECONDARY IGNITION PATTERN OK?

NO

REPAIR THE FAULTY COMPONENT(S) IN THE SECONDARY IGNITION SYSTEM.*

YES

MOMENTARILY REMOVE & REINSTALL EACH PLUG WIRE FROM THE IGNITION COIL OR DISTRIBUTOR...

ONE AT A TIME, WHILE OBSERVING THE SECONDARY KV PEAK LINE.

IS THE OPEN CIRCUIT SECONDARY VOLTAGE AT LEAST 25KV FOR EACH WIRE? YES

NO

REPLACE THE IGNITION COIL.*

NOTE: IN THE NEXT STEP DO NOT SPRAY INDUCTIVE PICKUP.

WITH A SPRAY BOTTLE SPRAY THE IGNITION CABLES WITH WATER AND MONITOR IGNITION PATTERN.

DID IGNITION PATTERN CHANGE?

YES

REPLACE IGNITION CABLES AS NECESSARY.*

NO

TURN ENGINE OFF. REMOVE ALL SPARK PLUGS & ASD RELAY.

USING APPROPRIATE PRESSURE GAUGE, TEST ALL CYLINDERS FOR PROPER COMPRESSION.

DO ALL CYLINDERS HAVE A MINIMUM COMPRESSION OF 100 PSI AND WITHIN 25% OF EACH OTHER? YES

NO

REPAIR ENGINE MECHANICAL PROBLEM AS NECESSARY.*

CONTINUE TEST TC-107A ON THE NEXT PAGE.

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
419

T TEST TC-107A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - CYLINDER #1, #2, #3, #4, #5, #6, #7, OR #8 MISFIRE

420

TEST TC-107A CONTINUED - REPAIRING - CYLINDER #1, #2, #3, #4, #5, #6, #7, OR #8 MISFIRE

TEST TC-107A CONTINUED FROM THE PREVIOUS PAGE.

REINSTALL SPARK PLUGS, PLUG WIRES AND ASD RELAY.

T R O U B L E C O D E T E S T S

START ENGINE, LET IDLE UNTIL NORMAL OPERATING TEMPERATURE IS REACHED.

WITH THE DRB, PERFORM INJECTOR KILL TEST.

MONITOR SCOPE PATTERN AND ENGINE RPM WHEN INJECTOR KILL IS ACTUATED.

DID INJECTOR KILL TEST SHOW A WEAK CYLINDER?

YES

INSPECT LOW CYLINDER FOR MECHANICAL PROBLEMS, IF OK. REPLACE APPROPRIATE INJECTOR.*

NO

TURN ENGINE OFF, CONNECT A VACUUM GAUGE TO MANIFOLD VACUUM. START ENGINE, LET IDLE.

PARKING BRAKE ON GEAR SHIFT IN THE NEUTRAL POSITION. READ VACUUM GAUGE.

DOES THE VACUUM GAUGE READ AT LEAST 13 INCHES OF VACUUM?

NO

PERFORM TEST TEST NTC-22A.

YES

INSPECT VALVE TRAIN AND TIMING OF THE CYLINDER WITH THE TROUBLE CODE.

IS THE VALVE TIMING OK?

NO

REPAIR OR REPLACE ENGINE COMPONENTS AS NECESSARY.*

YES

NOTE: AN INACCURATE SPEED SENSOR READING (TOO HIGH) MAY CAUSE THIS CODE TO SET INTERMITTENTLY.

NOTE: CHECK TSB’S AND FLASH UPDATES THAT MAY APPLY TO THIS CODE BEFORE NEXT REPAIR.

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
421

T TEST TC-112A REPAIRING - CATALIYTIC CONVERTER EFFICIENCY FAILURE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

422

TEST TC-112A REPAIRING - CATALIYTIC CONVERTER EFFICIENCY FAILURE
Perform DTC TEST Before Proceeding

START TEST TC-112A.

NOTE: ANY OTHER O2 SENSOR TROUBLE CODES OR T.S.B.’S SHOULD BE REPAIRED BEFORE PROCEEDING.

ARE THERE ANY OTHER TROUBLE CODES OR T.S.B.’S THAT APPLY?

YES

PERFORM THE DTC TEST OR T.S.B.’S THAT APPLY.

T R O U B L E C O D E T E S T S

NO

REFER TO FIGURE 1 FOR POSSIBLE TROUBLE CODE CAUSES.

START ENGINE AND LET IDLE.

CHECK THE EXHAUST SYSTEM FOR LEAKS BETWEEN THE ENGINE AND THE 1/2 O2 SENSOR.

IS THERE ANY EXHAUST LEAK?

YES

REPAIR OR REPLACE LEAKING EXHAUST PARTS AS NECESSARY.*

NO

NOTE: CHECK THE EXHAUST FOR EXCESSIVE SMOKE FROM INTERNAL OIL OR COOLANT LEAKS.

IS THERE AN OIL OR COOLANT CONSUMPTION CONDITION PRESENT?

YES

REPAIR ENGINE MECHANICAL AS NECESSARY, AND REPLACE CATALYTIC CONVERTER.*

NO

NOTE: A NEW DOWNSTREAM O2 SENSOR ALONG WITH AN AGING UPSTREAM O2...

SENSOR MAY CAUSE THIS TROUBLE CODE TO SET.

HAS THE DOWNSTREAM OXYGEN SENSOR BEEN REPLACED WITHIN THE LAST 5000 MILES? YES

NO

REPLACE THE CATALYTIC CONVERTER.*

HAS THE UPSTREAM OXYGEN SENSOR BEEN REPLACED WITHIN THE LAST 5000 MILES? NO

YES

REPLACE THE CATALYTIC CONVERTER.*

REPLACE THE UPSTREAM OXYGEN SENSOR.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
423

T TEST TC-113A REPAIRING - EVAP PURGE FLOW MONITOR FAILURE R O Perform TEST DTC Before Proceeding U 1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 B TSB 26-06-97 June, 1997 L E C O D E T E S T S
FIG. 1
WITHOUT LDP

WITH LDP

424

TEST TC-113A REPAIRING - EVAP PURGE FLOW MONITOR FAILURE
Perform TEST DTC Before Proceeding
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997
NOTE: REPLACING THE POWERTRAIN CONTROL MODULE WILL NOT CORRECT THIS PROBLEM. NOTE: CAREFULLY INSPECT ALL VACUUM HOSES FOR PROPER ROUTING AND FOR PINCHED OR...

START TEST TC-113A.

WITH THE DRB, ERASE CODES.

T R O U B L E C O D E T E S T S

PLUGGED HOSES FROM ENGINE TO EVAP SOLENOID TO GAS TANK.

ARE ALL VACUUM HOSES OK?

NO

REPAIR THE VACUUM HOSES AS NECESSARY.*

YES

START ENGINE. ALLOW ENGINE TO REACH NORMAL OPERATING TEMPERATURE (ABOVE 170 DEG.).

TURN THE ENGINE OFF (IGN. OFF).

DISCONNECT THE PURGE VACUUM HOSE AT THE SOLENOID THAT GOES TO THE CANISTER.

START THE ENGINE. THERE SHOULD BE NO FLOW THROUGH THE SOLENOID FROM 1 TO 2 MINUTES.

IS THE PURGE SOLENOID ALLOWING VACUUM THROUGH THE SOLENOID WITHIN 1 MINUTE? NO

YES

PERFORM TEST TC-113C.

AFTER 90 SECONDS, THE PURGE SOLENOID WILL ALLOW VACUUM TO...

CYCLE INTERMITTENTLY AT A STEADY RATE.

IS PURGE SOLENOID ALLOWING VACUUM TO CYCLE THROUGH INTERMITTENTLY AT A STEADY RATE? YES

NO

CONTINUE TEST TC-113A ON THE NEXT PAGE.

NOTE: IN THE NEXT STEPS, DO NOT USE MORE THAN FIVE (5) PSI.

KEY OFF, ATTEMPT TO BLOW AIR THROUGH VACUUM LINE THAT GOES TO CANISTER.

DOES THE CANISTER AND VACUUM LINE ALLOW AIR TO PASS?

YES

SOLENOID AND HOSES ARE OK. FIG. 1

NO

PERFORM TEST TC-113B.

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
425

T TEST TC-113A CONTINUED - REPAIRING - EVAP PURGE FLOW MONITOR FAILURE R O Perform TEST DTC Before Proceeding U AB BODY AN BODY 1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 B TSB 26-06-97 June, 1997 L E C O D E T E S T S
FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ 4.0L ZJ 5.2L

FIG. 4

FIG. 5
426

FIG. 6

TEST TC-113A CONTINUED - REPAIRING - EVAP PURGE FLOW MONITOR FAILURE
Perform TEST DTC Before Proceeding
TEST TC-113A CONTINUED FROM THE PREVIOUS PAGE. REMOVE THE HOSE’S AT THE EVAP SOLENOID. FIG. 1,2,3,4,5 OR 6
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

T R O U B L E C O D E

CONNECT A VACUUM GAUGE TO THE VACUUM HOSE THAT GOES TO THE THROTTLE BODY. FIG.1,2,3,4,5 OR 6

DOES THE GAUGE READ MANIFOLD VACUUM?

NO

REPAIR THE VACUUM HOSE OR THROTTLE BODY.*

YES

T E S T S

RECONNECT THE VACUUM LINE FROM THE THROTTLE BODY TO THE EVAP SOLENOID. FIG.1,2,3,4,5 OR 6

CONNECT A VACUUM GAUGE TO THE CANISTER SIDE OF THE EVAP SOLENOID. FIG.1,2,3,4,5 OR 6

DOES THE VACUUM GAUGE READ 5" OF VACUUM +/- 2"?

NO

REPLACE THE EVAP SOLENOID.*

YES

CONNECT AN AUXILIARY VACUUM SUPPLY TO THE HOSE GOING TO THE CANISTER. ACHIEVE > 2" OF VACUUM.

DOES CANISTER HOLD MORE THAN 2" OF VACUUM?

NO

REPLACE THE EVAP SOLENOID.*

YES

CHECK FOR A PLUGGED HOSE OR PLUGGED VENT PORT.

IS THE HOSE PLUGGED?

YES

REPAIR AS NECESSARY.*

NO

IS THE VENT PORT PLUGGED?

YES

CLEAN THE PLUGGED VENT AND RETEST.*

NO

REPLACE THE EVAP CANISTER.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
427

T TEST TC-113B CONTINUED - REPAIRING - EVAP PURGE FLOW MONITOR FAILURE R O Perform TEST TC-113A Before Proceeding U AB BODY AN BODY 1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 B TSB 26-06-97 June, 1997 L E C O D E T E S T S
FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ 4.0L ZJ 5.2L

FIG. 4

FIG. 5
428

FIG. 6

TEST TC-113B CONTINUED - REPAIRING - EVAP PURGE FLOW MONITOR FAILURE
Perform TEST TC-113A Before Proceeding
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

START TEST TC-113B.

DISCONNECT THE PURGE VACUUM LINE AT THE CANISTER. FIG.1,2,3,4,5 OR 6

T R O U B L E C O D E

ATTEMPT TO BLOW AIR THROUGH THE VACUUM LINE THAT GOES TO THE CANISTER.

DOES THE VACUUM LINE ALLOW AIR TO PASS?

NO

REPAIR OR REPLACE THE VACUUM LINE.*

YES

T E S T S

CHECK FOR A PLUGGED VENT PORT ON CANISTER.

IS THE VENT PORT PLUGGED?

NO

REPLACE THE EVAPORATIVE CANISTER.*

YES

REPAIR THE PLUGGED VENT PORT AND RETEST.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
429

T TEST TC-113C REPAIRING - EVAP PURGE FLOW MONITOR FAILURE R O Perform TEST TC-113A Before Proceeding U NOTES B L E C O D E T E S T S

430

TEST TC-113C REPAIRING - EVAP PURGE FLOW MONITOR FAILURE
Perform TEST TC-113A Before Proceeding
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

START TEST TC-113C.

REMOVE THE PURGE SOLENOID AND TAP THE PORTS AGAINST A CLEAN SOLID SURFACE.

T R O U B L E C O D E T E S T S

DID ANY FOREIGN MATERIAL FALL OUT?

NO

REPLACE THE EVAP PURGE SOLENOID.*

YES

INSPECT THE LINE FROM THE PURGE SOLENOID TO THE CANISTER.

IS THE LINE DISCONNECTED, RIPPED OR CUT? YES

NO

CLEAN OUT LINE AND REPLACE THE EVAP PURGE SOLENOID AND CANISTER.*

REPAIR THE LINE AND REPLACE THE PURGE SOLENOID.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
431

T TEST TC-114A REPAIRING - P/N SWITCH STUCK IN PARK OR IN GEAR R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
432

TEST TC-114A REPAIRING - P/N SWITCH STUCK IN PARK OR IN GEAR
Perform TEST DTC Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-114A.

WITH THE DRB, READ THE PARK/NEUTRAL SWITCH INPUT STATE.

WHILE MOVING GEAR SELECTOR IN & OUT OF PARK & REVERSE, WATCH THE DRB DISPLAY.

DID THE DISPLAY SHOW "P/N" AND "D/R"?

NO

CONTINUE TEST TC-114A ON THE NEXT PAGE.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

INSPECT THE WIRING AND CONNECTORS RELATING TO PARK NEUTRAL POSITION SWITCH.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
433

T TEST TC-114A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - P/N SWITCH STUCK IN PARK OR IN GEAR

FIG. 1
AN AND XJ BODIES

FIG. 2
BR AND ZJ BODIES

FIG. 3
434

TEST TC-114A CONTINUED - REPAIRING - P/N SWITCH STUCK IN PARK OR IN GEAR

TEST TC-114A CONTINUED FROM PREVIOUS PAGE.

KEY OFF. PUT THE GEAR SELECTOR IN PARK.

T R O U B L E C O D E

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

T E S T S
OBSERVE OHMMETER DISPLAY WHILE MOVING GEAR SELECTOR FROM PARK TO REVERSE AND BACK TO PARK. DID THE DISPLAY SWITCH FROM BELOW 10.0 OHMS TO ABOVE 10.0 OHMS?

MEASURE THE RESISTANCE BETWEEN THE P/N SWITCH SENSE CIRCUIT AND GROUND. FIG. 1, 2 OR 3.

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

DID THE DISPLAY STAY BELOW 10.0 OHMS AT ALL TIMES?

NO

CONTINUE TEST TC-114A ON THE NEXT PAGE.

YES

DISCONNECT THE PARK NEUTRAL SWITCH.** SEE GENERAL INFO 4.7

MEASURE THE RESISTANCE BETWEEN THE P/N SWITCH SENSE CIRCUIT AND GROUND. FIG. 1, 2 OR 3.

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR P/N SWITCH SENSE CKT FOR A SHORT TO GROUND.*

NO

REPAIR OR REPLACE STUCK PARK NEUTRAL SWITCH.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
435

T TEST TC-114A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - P/N SWITCH STUCK IN PARK OR IN GEAR
AN BODY

FIG. 1
BR BODY XJ BODY 4.0L AUTO

FIG. 2

FIG. 3
XJ BODY ALL OTHERS ZJ BODY

FIG. 4

FIG. 5
436

FIG. 6

TEST TC-114A CONTINUED - REPAIRING - P/N SWITCH STUCK IN PARK OR IN GEAR

T R O U B L E C O D E T E S T S

TEST TC-114A CONTINUED FROM PREVIOUS PAGE.

DISCONNECT THE PARK/NEUTRAL POSITION SWITCH CONNECTOR.** SEE GENERAL INFO 4.7

MEASURE THE RESISTANCE OF THE P/N SWITCH SENSE CIRCUIT...

FROM THE PCM CONNECTOR TO THE P/N SWITCH CONNECTOR. FIG. 1,2,3,4,5 OR 6

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE PARK/NEUTRAL POSITION SWITCH.*

NO

REPAIR OPEN P/N SWITCH SENSE CKT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
437

T TEST TC-115A REPAIRING - POWER STEERING SWITCH FAILURE R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

XJ BODY

FIG. 1

FIG. 2
438

TEST TC-115A REPAIRING - POWER STEERING SWITCH FAILURE
Perform TEST DTC Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-115A

START ENGINE. WITH THE DRB, MONITOR THE P/S SW. TURN THE STEERING WHEEL TO BOTH EXTREMES.

DID THE POWER STEERING PRESSURE SWITCH CHANGE STATE?

NO

CONTINUE TEST TC-115A ON THE NEXT PAGE.

YES

USING THE SCHEMATIC, INSPECT THE WIRING AND HARNESSES.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH THE DRB MONITOR THE PS SWITCH STATE, WHILE WIGGLING THE HARNESS

DID THE POWER STEERING SWITCH CHANGE STATE?

YES

REPAIR THE HARNESS AS NECESSARY.*

NO

REFER TO FIGURE 1 AND FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

439

T TEST TC-115A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - POWER STEERING SWITCH FAILURE

XJ BODY

FIG. 1
XJ BODY

FIG. 2
440

TEST TC-115A CONTINUED - REPAIRING - POWER STEERING SWITCH FAILURE

TEST TC-115A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF. DISCONNECT THE POWER STEERING PRESSURE SWITCH.** SEE GENERAL INFO 4.7

CONNECT A JUMPER WIRE TO THE POWER STEERING PRESSURE SWITCH CIRCUIT. FIG. 1

T R O U B L E C O D E T E S T S

WITH THE DRB, MONITOR THE POWER STEERING PRESSURE SWITCH.

TOUCH THE OTHER END OF THE JUMPER TO GROUND 5 TIMES.

DID THE POWER STEERING PRESSURE SWITCH CHANGE STATE?

YES CONTINUE TEST TC-115A ON THE NEXT PAGE.

NO

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

WITH AN OHMMETER, MEASURE THE P/S PRESSURE SW CKT FROM THE PCM TO THE CONN. FIG. 2

WAS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN POWER STEERING PRESSURE SWITCH CIRCUIT.*

YES

USING AN OHMMETER, MEASURE THE P/S PRESSURE SWITCH CKT AT THE P/S SW TO GROUND. FIG. 1

WAS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE POWER STEERING PRESSURE SWITCH CIRCUIT FOR A SHORT TO GROUND.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
441

T TEST TC-115A R O XJ BODY U B L E C O D E T E S T S

CONTINUED - REPAIRING - POWER STEERING SWITCH FAILURE

FIG. 1

442

TEST TC-115A CONTINUED - REPAIRING - POWER STEERING SWITCH FAILURE

T R O U B L E C O D E T E S T S

TEST TC-115A CONTINUED FROM THE PREVIOUS PAGE.

USING AN OHMMETER, MEASURE THE GROUND CIRCUIT AT P/S PRESSURE SW CONN. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN GROUND CIRCUIT.*

YES

REPLACE THE POWER STEERING PRESSURE SWITCH.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
443

T TEST TC-118A REPAIRING - FUEL SYSTEM 1/1 RICH R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

444

TEST TC-118A REPAIRING - FUEL SYSTEM 1/1 RICH
Perform TEST DTC Before Proceeding

START TEST TC-118A.

NOTE: ANY OTHER O2 SENSOR TROUBLE CODES OR T.S.B.’S SHOULD BE REPAIRED BEFORE PRODEEDING.

ARE THERE ANY OTHER TROUBLE CODES OR T.S.B.’S THAT APPLY?

YES

PERFORM THE DTC TEST OR T.S.B.’S THAT APPLY.

T R O U B L E C O D E T E S T S

NO

REFER TO FIGURE 1 FOR POSSIBLE TROUBLE CODE CAUSES.

PERFORM O2 HEATER TEST TC-103A.

DID TEST TC-103A PASS?

NO TEST COMPLETE. *

YES

TURN ENGINE OFF AND KEY ON.

WITH THE DRB, READ THE LONG TERM ADAPTIVE MEMORY VALUE.

IS THE LONG TERM ADAPTIVE MEMORY BETWEEN -20% TO -38%?

NO

THE CONDITION REQUIRED TO SET THIS TROUBLE CODE IS NO LONGER PRESENT. TEST COMPLETE.*

YES

PERFORM TEST TC-118B.

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
445

T TEST TC-118B REPAIRING - FUEL SYSTEM 1/1 RICH R O Perform TEST TC-118A Before Proceeding U 5.9L HD, 8.0L HD AND 8.0L CAL/MD B L E C O D E T E S T S

ALL CNG

ALL OTHERS

446

TEST TC-118B REPAIRING - FUEL SYSTEM 1/1 RICH
Perform TEST TC-118A Before Proceeding

Using the test schematic as a guide, make sure all the wiring and connectors are okay. Perform each of the following tests in the order listed below. If a test passes, continue to the next test until the problem is found. Fuel Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-3A Coolant Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-4A Throttle Position Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST-NTC5A MAP Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-6A Evaporative Emission System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-12A Engine Mechanical Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-22A

T R O U B L E C O D E T E S T S

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
447

T TEST TC-119A REPAIRING - FUEL SYSTEM 1/1 LEAN R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

448

TEST TC-119A REPAIRING - FUEL SYSTEM 1/1 LEAN
Perform TEST DTC Before Proceeding

START TEST TC-119A.

NOTE: VERY LOW FUEL LEVEL COULD CAUSE THIS TROUBLE CODE TO SET. MAKE SURE TANK IS AT LEAST 1/4 FULL

DID THE VEHICLE RUN OUT OF FUEL SHORTLY BEFORE COMING IN?

YES

ERASE TROUBLE CODES. TEST COMPLETE.*

T R O U B L E C O D E

NO

REFER TO FIGURE 1 FOR POSSIBLE TROUBLE CODE CAUSES.

WITH THE DRB, READ ALL TROUBLE CODES.

ARE THERE ANY OTHER TROUBLE CODES OR T.S.B.’S THAT APPLY?

YES

PERFORM THE DTC TEST OR THE T.S.B.’S THAT APPLY..

NO

T E S T S

START THE ENGINE AND ALLOW IT TO REACH NORMAL OPERATING TEMPERATURE.

CHECK SYSTEM BETWEEN THE O2

EXHAUST FOR LEAKS ENGINE AND SENSORS.

ARE THERE ANY EXHAUST LEAKS?

YES

REPAIR OR REPLACE EXHAUST COMPONENTS AS NECESSARY.*

NO

WITH THE DRB, MONITOR THE 1/1 O2 SENSOR STATE...

FOR 20 SECONDS OR MORE.

IS THE 1/1 O2S STATE SWITCHING BETWEEN "LEAN-CENTER-RICH" TWICE OR MORE IN 20 SECONDS? NO

THE CONTITION YES REQUIRED TO SET THIS TROUBLE CODE IS NO LONGER PRESENT. TEST COMPLETE.*

WITH THE DRB, READ THE LONG TERM ADAPTIVE MEMORY VALUES.

ARE ANY OF THE LONG TERM ADAPTIVE MEMORY BETWEEN +18% AND +25% ?

NO

THE CONDITION REQUIRED TO SET THIS TROUBLE CODE IS NO LONGER PRESENT. TEST COMPLETE.*

YES

PERFORM TEST TC-119B.

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
449

T TEST TC-119B REPAIRING - FUEL SYSTEM 1/1 LEAN R O Perform TEST TC-119A Before Proceeding U 5.9L HD, 8.0L HD AND 8.0L CAL/MD B L E C O D E T E S T S

ALL CNG

ALL OTHERS

450

TEST TC-119B REPAIRING - FUEL SYSTEM 1/1 LEAN
Perform TEST TC-119A Before Proceeding

Using the test schematic as a guide, make sure all the wiring and connectors are okay. Perform each of the following tests in the order listed below. If a test passes, continue to the next test until the problem is found. Fuel Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-3A Coolant Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-4A Throttle Position Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-5A MAP Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-6A Evaporative Emission System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-13A Engine Mechanical Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST-NTC22A

T R O U B L E C O D E T E S T S

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
451

T TEST TC-120A REPAIRING - FUEL SYSTEM 2/1 RICH R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

452

TEST TC-120A REPAIRING - FUEL SYSTEM 2/1 RICH
Perform TEST DTC Before Proceeding

START TEST TC-120A.

NOTE: ANY OTHER O2 SENSOR TROUBLE CODES OR T.S.B.’S MUST BE REPAIRED BEFORE PROCEEDING.

ARE THERE ANY OTHER TROUBLE CODES OR T.S.B.’S THAT APPLY?

YES

PERFORM THE DTC TEST OR T.S.B.’S THAT APPLY.

T R O U B L E C O D E T E S T S

NO

REFER TO FIGURE 1 FOR POSSIBLE TROUBLE CODE CAUSES.

PERFORM O2 HEATER TEST TC-124A.

DID TEST TC-124A PASS?

NO TEST COMPLETE. *

YES

TURN ENGINE OFF AND KEY ON.

WITH THE DRB, READ THE LONG TERM ADAPTIVE MEMORY VALUE.

IS THE LONG TERM ADAPTIVE MEMORY BETWEEN -20% TO -38%?

NO

THE CONDITION REQUIRED TO SET THIS TROUBLE CODE IS NO LONGER PRESENT. TEST COMPLETE.*

YES

PERFORM TEST TC-120B.

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
453

T TEST TC-120B REPAIRING - FUEL SYSTEM 2/1 RICH R O Perform TEST TC-120A Before Proceeding 5.9L HD, 8.0L HD AND 8.0L CAL/MD U B L E C O D E T E S T S

454

TEST TC-120B REPAIRING - FUEL SYSTEM 2/1 RICH
Perform TEST TC-120A Before Proceeding

Using the test schematic as a guide, make sure all the wiring and connectors are okay. Perform each of the following tests in the order listed below. If a test passes, continue to the next test until the problem is found. Fuel Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-3A Ignition System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-2A Coolant Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-4A MAP Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-6A Engine Mechanical Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-22A

T R O U B L E C O D E T E S T S

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
455

T TEST TC-121A REPAIRING - FUEL SYSTEM 2/1 LEAN R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

456

TEST TC-121A REPAIRING - FUEL SYSTEM 2/1 LEAN
Perform TEST DTC Before Proceeding

START TEST TC-121A.

NOTE: VERY LOW FUEL LEVEL COULD CAUSE THIS TROUBLE CODE TO SET. MAKE SURE TANK IS AT LEAST 1/4 FULL

DID THE VEHICLE RUN OUT OF FUEL SHORTLY BEFORE COMING IN?

YES

ERASE TROUBLE CODES. TEST COMPLETE.*

T R O U B L E C O D E

NO

REFER TO FIGURE 1 FOR POSSIBLE TROUBLE CODE CAUSES.

WITH THE DRB, READ ALL TROUBLE CODES.

ARE THERE ANY OTHER TROUBLE CODES OR T.S.B.’S THAT APPLY?

YES

PERFORM THE DTC TEST OR THE T.S.B.’S THAT APPLY..

NO

T E S T S

START THE ENGINE AND ALLOW IT TO REACH NORMAL OPERATING TEMPERATURE.

CHECK SYSTEM BETWEEN THE O2

EXHAUST FOR LEAKS ENGINE AND SENSORS.

ARE THERE ANY EXHAUST LEAKS?

YES

REPAIR OR REPLACE EXHAUST COMPONENTS AS NECESSARY.*

NO

WITH THE DRB, MONITOR THE 2/1 O2 SENSOR STATE...

FOR 20 SECONDS OR MORE.

IS THE 2/1 O2S STATE SWITCHING BETWEEN "LEAN-CENTER-RICH" TWICE OR MORE IN 20 SECONDS? NO

THE CONTITION YES REQUIRED TO SET THIS TROUBLE CODE IS NO LONGER PRESENT. TEST COMPLETE.*

WITH THE DRB, READ THE LONG TERM ADAPTIVE MEMORY VALUES.

ARE ANY OF THE LONG TERM ADAPTIVE MEMORY BETWEEN +20% AND +32% ?

NO

THE CONDITION REQUIRED TO SET THIS TROUBLE CODE IS NO LONGER PRESENT. TEST COMPLETE.*

YES

PERFORM TEST TC-121B.

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
457

T TEST TC-121B REPAIRING - FUEL SYSTEM 2/1 LEAN R O Perform TEST TC-120A Before Proceeding 5.9L HD, 8.0L HD AND 8.0L CAL/MD U B L E C O D E T E S T S

458

TEST TC-121B REPAIRING - FUEL SYSTEM 2/1 LEAN
Perform TEST TC-120A Before Proceeding

Using the test schematic as a guide, make sure all the wiring and connectors are okay. Perform each of the following tests in the order listed below. If a test passes, continue to the next test until the problem is found. Fuel Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-3A Ignition System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-2A Coolant Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-4A MAP Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-6A Engine Mechanical Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TEST NTC-22A

T R O U B L E C O D E T E S T S

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
459

T TEST TC-122A REPAIRING - 2/1 O2 SENSOR SLOW RESPONSE R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1
TYPICAL CONNECTOR

FIG. 2
460

TEST TC-122A REPAIRING - 2/1 O2 SENSOR SLOW RESPONSE
Perform TEST DTC Before Proceeding

START TEST TC-122A.

REFER TO THE FIGURE FOR POSSIBLE TROUBLE CODE CAUSES. FIG. 1

T R O U B L E C O D E

START THE ENGINE.

CHECK THE EXHAUST SYSTEM FOR LEAKS BETWEEN THE ENGINE AND THE CATALYST.

IS THERE ANY EXHAUST LEAK?

YES

REPAIR OR REPLACE LEAKING EXHAUST PARTS AS NECESSARY.*

NO

T E S T S

NOTE: CHECK THE EXHAUST FOR EXCESSIVE SMOKE CAUSED BY OIL OR COOLANT CONSUMPTION.

IS THERE AN OIL OR COOLANT CONSUMPTION CONDITION PRESENT?

YES

REPAIR ENGINE MECHANICAL, REPLACE THE 2/1 O2 SENSOR.*

NO

KEY OFF. DISCONNECT THE 2/1 OXYGEN SENSOR.** SEE GENERAL INFO 4.4

INSPECT THE CONNECTORS AND TERMINALS.

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE FROM THE O2 SENSOR...

GROUND CIRCUIT TO A GOOD GROUND. FIG. 2

IS THE RESISTEANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN 2/1 O2 SENSOR GROUND CIRCUIT.*

YES

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

INSPECT THE CONNECTOR.

IS THE CONNECTOR CONDITION OK?

NO

REPAIR AS NECESSARY.*

YES

REPLACE THE 2/1 OXYGEN SENSOR.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
461

T TEST TC-124A REPAIRING - 2/1 O2 SENSOR HEATER FAILURE R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

462

TEST TC-124A REPAIRING - 2/1 O2 SENSOR HEATER FAILURE
Perform TEST DTC Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-124A.

TURN IGNITION ON (ENGINE OFF).

WITH THE DRB, MONITOR THE 2/1 O2 SENSOR VOLTAGE FOR A FEW MINUTES.

WAIT FOR THE VOLTAGE READING TO STABILIZE ABOVE 4.5 VOLTS.

WITH THE DRB, ACTUATE THE O2 SENSOR HEATER TEST.

MONITOR THE 2/1 O2 SENSOR VOLTAGE FOR UP TO TWO MINUTES.

IS THE 2/1 O2 SENSOR VOLTAGE ABOVE 1.0 VOLT?

YES

CONTINUE TEST TC-124A ON THE NEXT PAGE.

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

REFER TO GENERAL INFO 3.3.2 FOR INFORMATION ON INACTIVE TROUBLE CODES.

STOP ALL ACTUATOR TESTS. TEST COMPLETE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
463

T TEST TC-124A CONTINUED - REPAIRING - 2/1 O2 SENSOR HEATER FAILURE R O U TYPICAL CONNECTOR B L E C O D E T E S T S

FIG. 1
TYPICAL CONNECTOR

FIG. 2
464

TEST TC-124A CONTINUED - REPAIRING - 2/1 O2 SENSOR HEATER FAILURE

TEST TC-124A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE 2/1 O2 SENSOR CONNECTOR AND INSPECT ALL TERMINALS.** SEE GENERAL INFO 4.4

ARE ANY TERMINALS CORRODED, DAMAGED, PUSHED OUT OR MISWIRED.

T R O U B L E
REPAIR AS NECESSARY.*

YES

NO

C O D E T E S T S

WITH THE O2 HEATER TEST STILL RUNNING. MEASURE THE VOLTAGE...

OF THE ASD RELAY OUTPUT AT THE O2 SENSOR CONNECTOR. FIG. 1

IS THE VOLTAGE BELOW 10.0 VOLTS?

YES

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

NO

USING AN OHMMETER, MEASURE THE 2/1 O2 SENSOR HEATER ELEMENT FROM THE ASD RELAY...

OUTPUT TO THE HEATER GROUND AT THE O2 SENSOR CONNECTOR. FIG. 2

IS THE RESISTANCE BETWEEN 4.0 AND 7.0 OHMS?

NO

REPLACE THE 2/1 OXYGEN SENSOR.*

YES

USING AN OHMMETER, MEASURE THE HEATER GROUND CIRCUIT FROM THE...

O2 SENSOR CONNECTOR TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN GROUND CIRCUIT TO THE 2/1 O2 SENSOR.*

YES

REPLACE THE 2/1 OXYGEN SENSOR.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
465

T TEST TC-126A REPAIRING - 1/2 O2 SENSOR SHORTED TO VOLTAGE R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

466

TEST TC-126A REPAIRING - 1/2 O2 SENSOR SHORTED TO VOLTAGE
Perform TEST DTC Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-126A.

START ENGINE, LET IDLE FOR AT LEAST 5 MINUTES.

WITH THE DRB, READ THE 1/2 O2 SENSOR VOLTAGE.

IS THE 1/2 O2 SENSOR VOLTAGE ABOVE 4.97 VOLTS?

NO

CONTINUE TEST TC-126A ON THE NEXT PAGE.

YES

DISCONNECT THE 1/2 O2 SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

IS THE 1/2 O2 SENSOR VOLTAGE ABOVE 4.97 VOLTS?

NO

REPLACE THE 1/2 OXYGEN SENSOR.*

YES

REPAIR THE 1/2 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
467

T TEST TC-126A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 1/2 O2 SENSOR SHORTED TO VOLTAGE

468

TEST TC-126A CONTINUED - REPAIRING - 1/2 O2 SENSOR SHORTED TO VOLTAGE

TEST TC-126A CONTINUED FROM THE PREVIOUS PAGE.

WITH THE ENGINE STILL IDLING.

T R O U B L E C O D E

WIGGLE THE 1/2 O2 SENSOR CONNECTOR AND HARNESS.

WHILE WIGGLING THE HARNESS, WATCH THE DRB DISPLAY.

DID THE 1/2 O2 SENSOR VOLTAGE GO ABOVE 1.2 VOLTS AT ANY TIME?

YES

REPAIR THE HARNESS OR CONNECTOR THAT HAS THE INTERMITTENT SHORT TO VOLTAGE.*

NO

T E S T S

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT.

TURN KEY OFF. DISCONNECT THE PCM AND THE 1/2 O2 SENSOR CONNECTOR.**

INSPECT ALL TERMINALS.

WERE THERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

USING A SCHEMATIC AS A GUIDE, INSPECT THE WIRING.

WERE THERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
469

T TEST TC-128A REPAIRING - CLOSED LOOP TEMP NOT REACHED R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1
470

TEST TC-128A REPAIRING - CLOSED LOOP TEMP NOT REACHED
Perform TEST DTC Before Proceeding

START TEST TC-128A.

THIS TEST PROCEDURE WILL BE INVALID IF THE THERMOSTAT IS STUCK OPEN.

IS THE THERMOSTAT OPERATING CORRECTLY?

NO

REPLACE THE THERMOSTAT.*

T R O U B L E C O D E T E S T S

YES

TO HAVE A CLEAR UNDERSTANDING OF THIS CODE PLEASE READ FIGURE 1.

RUN ENGINE UNTIL ENGINE TEMPERATURE IS ABOVE 80 DEGREES F.

KEY OFF, DISCONNECT THE ENGINE COOLANT TEMPERATURE SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED?

YES

CLEAN OR REPAIR CONNECTOR AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE ENGINE COOLANT SENSOR.

IS THE RESISTANCE BELOW 11.00 K OHM?

NO

REPLACE ENGINE COOLANT TEMPERATURE SENSOR.*

YES

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED?

YES

CLEAN OR REPAIR CONNECTOR AS NECESSARY.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
471

T TEST TC-132A REPAIRING - TPS VOLTAGE DOES NOT AGREE WITH MAP R O Perform TEST DTC Before Proceeding U ZJ BODY B L E C O D E T E S T S

ALL OTHERS

FIG. 1
472

TEST TC-132A REPAIRING - TPS VOLTAGE DOES NOT AGREE WITH MAP
Perform TEST DTC Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-132A.

USING THE DRB, READ THE TROUBLE CODES.

IS ANY OTHER MAP SENSOR TROUBLE CODE PRESENT?

YES

PERFORM "DTC TEST".

NO

WITH THE DRB, READ THE MAP SENSOR VOLTAGE.

IS THE MAP SENSOR VOLTAGE BELOW 3.5 VOLTS?

YES

PERFORM TEST NTC-6A.

NO

START ENGINE.

WITH THE DRB, READ THE MAP SENSOR VOLTAGE.

DID THE MAP SENSOR VOLTAGE DROP FROM ABOVE 3.5 VOLTS TO BELOW 2.0 VOLTS?

NO

PERFORM TEST NTC-6A.

YES

NOTE: TO HAVE A CLEAR UNDERSTANDING OF THIS TROUBLE CODE READ FIGURE 1.

CONTINUE TEST TC-132A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
473

T TEST TC-132A CONTINUED - REPAIRING - TPS VOLTAGE DOES NOT AGREE WITH MAP R O U AB, AN, BR AND XJ BODIES B L E C O D E T E S T S
FIG.1
BR DIESEL

FIG. 2
ZJ BODY

FIG. 3
474

TEST TC-132A CONTINUED - REPAIRING - TPS VOLTAGE DOES NOT AGREE WITH MAP

TEST TC-132A CONTINUED FROM THE PREVIOUS PAGE.

CHECK THROTTLE PLATE AND LINKAGE FOR A BINDING CONDITION.

ENSURE THE THROTTLE LINKAGE IS AT THE IDLE POSITION.

T R O U B L E C O D E

NOTE: TP SENSOR GND CIRCUIT AND THE 5-VOLT SUPPLY CKT SWITCHED WILL CAUSE THIS CODE TO APPEAR.

DISCONNECT THE TP SENSOR.** SEE GENERAL INFO 4.4

T E S T S

INSPECT TP SENSOR WIRE COLORS FOR THE CORRECT CAVITIES.** FIG. 1, 2 OR 3

IS ANY TERMINAL DAMAGED PUSHED OUT OR CORRODED?

YES

CLEAN OR REPAIR CONNECTOR AS NECESSARY.*

NO

USING A VOLTMETER, MEASURE THE 5-VOLT SUPPLY CIRCUIT. FIG. 1, 2 OR 3

IS THE VOLTAGE BELOW 5.0 VOLTS?

YES

REPAIR THE OPEN 5-VOLT SUPPLY CIRCUIT TO TP SENSOR.*

NO

RECONNECT THROTTLE POSITION SENSOR CONNECTOR. TURN IGNITION ON (ENGINE OFF)

WITH THE DRB, READ THE THROTTLE POSITION SENSOR VOLTAGE.

IS THE THROTTLE POSITION SENSOR VOLTAGE ABOVE 1.0 VOLTS?

YES

REPLACE THE THROTTLE POSITION SENSOR.*

NO

CONTINUE TEST TC-132A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
475

T TEST TC-132A R O U ZJ BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - TPS VOLTAGE DOES NOT AGREE WITH MAP

ALL OTHERS

FIG.1
476

TEST TC-132A CONTINUED - REPAIRING - TPS VOLTAGE DOES NOT AGREE WITH MAP

TEST TC-132A CONTINUED FROM THE PREVIOUS PAGE.

WHILE MONITORING THE DRB, SLOWLY OPEN AND CLOSE THE THROTTLE PLATE.

T R O U B L E C O D E T E S T S

NOTE: YOU MUST MOVE THE LINKAGE VERY SLOWLY WHILE LOOKING FOR A JUMP IN VOLTAGE.

IS THE VOLTAGE CHANGE SMOOTH?

NO

REPLACE THE THROTTLE POSITION SENSOR.*

YES

WHILE MONITORING THE DRB, OPEN THE THROTTLE PLATE TO WIDE OPEN THROTTLE.

IS THE THROTTLE POSITION SENSOR VOLTAGE ABOVE 3.5 VOLTS?

NO

REPLACE THE THROTTLE POSITION SENSOR.*

YES

USING THE SCHEMATIC AS A GUIDE, WIGGLE THE TP SENSOR HARNESS AND CONNECTORS TO PCM.

WHILE MONITORING THE DRB, OBSERVE FOR THE TP SENSOR VOLTAGE TO CHANGE.

DID THE TP SENSOR VOLTAGE CHANGE AT ANY TIME?

YES

REPAIR THE HARNESS OR CONNECTORS AS NECESSARY.*

NO

REFER TO FIGURE 1 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
477

T TEST TC-138A REPAIRING - TARGET IDLE NOT REACHED R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S
FIG.1
AB, AN, BR AND XJ BODIES

ZJ BODY

478

TEST TC-138A REPAIRING - TARGET IDLE NOT REACHED
Perform TEST DTC Before Proceeding

START TEST TC-138A.

TURN ENGINE OFF, IGNITION ON.

CHECK THROTTLE PLATE AND LINKAGE FOR A BINDING CONDITION.

T R O U B L E C O D E

THE THROTTLE LINKAGE MUST BE AT THE IDLE POSITION.

ENSURE THE THROTTLE PLATE IS FULLY CLOSED AND AGAINST ITS STOP.

IS THE THROTTLE PLATE AND LINKAGE OK?

NO

REPAIR AS NECESSARY.*

YES

T E S T S

START ENGINE, ALLOW TO IDLE FOR 60 SECONDS, IF THIS IS AN AUTO TRANS, PUT IN DRIVE.

WITH THE DRB READ TARGET IDLE AND ENGINE RPM.

IS THE ENGINE RPM WITHIN +200 OR -100 RPM OF TARGET IDLE?

YES

CONTINUE TEST TC-138A ON THE NEXT PAGE.

NO

FOR THIS TEST TO BE VALID THE ENGINE MUST NOT HAVE ANY VACUUM LEAKS.

CHECK ENGINE, BRAKE BOOSTER AND VACUUM HOSES FOR LEAKS.

ENSURE PCV VALVE IS THE CORRECT ONE AND IS OPERATING CORRECTLY.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH THE DRB IN SYSTEM TESTS, PERFORM THE IAC WIGGLE TEST.

THE IDLE SPEED SHOULD RAISE AND LOWER WITH THE DISPLAY.

DOES THE IDLE RAISE AND LOWER WITH THE DISPLAY?

NO

PERFORM TEST TC-25A.

YES

PERFORM TEST TC-138B.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
479

T TEST TC-138A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - TARGET IDLE NOT REACHED

FIG.1
AB, AN, BR AND XJ BODIES

ZJ BODY

480

TEST TC-138A CONTINUED - REPAIRING - TARGET IDLE NOT REACHED

TEST TC-138A CONTINUED FROM THE PREVIOUS PAGE.

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG.1

T R O U B L E C O D E T E S T S

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

START ENGINE. WITH THE DRB IN SYSTEM TESTS, PERFORM THE IAC WIGGLE TEST.

THE IDLE SPEED SHOULD RAISE AND LOWER WITH THE DISPLAY.

DOES THE IDLE RAISE AND LOWER WITH THE DISPLAY?

NO

PERFORM TEST TC-25A.

YES

WIGGLE THE WIRING HARNESS FROM THE IAC MOTOR TO THE POWERTRAIN CONTROL MODULE.

MONITOR THE ENGINE RPM.

DID THE IAC STOP OPERATING AT ANY TIME?

YES

REPAIR THE HARNESS OR CONNECTORS AS NECESSARY.*

NO

STOP THE IAC WIGGLE TEST.

REFER TO GENERAL INFO 3.3.2 FOR INFORMATION ON INACTIVE TROUBLE CODES.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
481

T TEST TC-138B R O U B L E C O D E T E S T S

REPAIRING - TARGET IDLE NOT REACHED

AB, AN, BR AND XJ BODIES

ZJ BODY

482

TEST TC-138B REPAIRING - TARGET IDLE NOT REACHED

START TEST TC-138B

TURN IGNITION OFF.

DISCONNECT THE PCV VALVE HOSE FROM THE INTAKE MANIFOLD AND CAP PORT AT INTAKE MANIFOLD.

T R O U B L E C O D E T E S T S

DISCONNECT THE IDLE PURGE HOSE FROM THE THROTTLE BODY.**

INSTALL MILLER TOOL #6714 TO THE PURGE HOSE PORT OF THE THROTTLE BODY.

START ENGINE. ALLOW ENGINE TO REACH OPERATING TEMPERATURE. (ABOVE 180 DEG.)

ACTUATE THE MIN. AIR FLOW.

IS THE ENGINE RPM BELOW 550?

NO

REPLACE THROTTLE BODY.*

YES

REMOVE THROTTLE BODY PER SERVICE MANUAL PROCEDURE.

WARNING: CLEAN THE THROTTLE BODY IN A WELL VENTILATED AREA AND WEAR RUBBER GLOVES.

WHILE HOLDING THE THROTTLE OPEN, SPRAY ENTIRE THROTTLE BODY BORE WITH MOPAR PARTS CLEANER.

USING A SOFT SCUFF PAD, CLEAN THE THROTTLE BODY BORE AND THROTTLE PLATE.

USING COMPRESSED AIR, DRY THE THROTTLE BODY AND INSTALL THROTTLE BODY ON MANIFOLD.

START ENGINE AND LET IDLE. WITH THE DRB, ACTUATE THE MIN. AIR FLOW.

IS THE ENGINE RPM BELOW 550?

YES

REPLACE THROTTLE BODY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
483

T TEST TC-140A REPAIRING - EGR SYSTEM FAILURE R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

484

TEST TC-140A REPAIRING - EGR SYSTEM FAILURE
Perform TEST DTC Before Proceeding

START TEST TC-140A.

START ENGINE AND LET IDLE.

T R O U B L E C O D E T E S T S

USE A VACUUM GAUGE IN THE FOLLOWING STEPS.

DISCONNECT THE EGR SOLENOID VACUUM SUPPLY AT THE EGR SOLENOID. FIG. 1

IS THERE 20" OF VACUUM PRESENT AT THE SOLENOID?

NO

REPAIR THE VACUUM SUPPLY TO THE EGR SOLENOID.*

YES

RECONNECT THE EGR SOLENOID VACUUM SUPPLY AT THE EGR SOLENOID. FIG. 1

DISCONNECT THE VACUUM LINE TO THE EGR VALVE.

USING THE DRB SELECT EGR SYSTEMS TEST. SELECT #3 (FLOW).

IS THERE 20" OF VACUUM PRESENT AT THE EGR VALVE.

NO

CONTINUE TEST TC-40A ON THE NEXT PAGE.

YES

AFTER 40 SECONDS OF FLOW OPERATION. RECORD THE VACUUM READING TO THE EGR VALVE.

PRESS #1 (NORMAL) ON THE DRB.

DID THE VACUUM DROP TO ZERO RAPIDLY?

NO

REPLACE THE EGR QUICK RELEASE VALVE.*

YES

RESELECT #3 (FLOW) FOR 40 SECONDS. CONNECT A VACUUM PUMP TO THE VACUUM PUMP SIDE OF THE...

VACUUM SUPPLY LINE TO THE EGR VALVE VACUUM REGULATOR SOLENOID AND APPLY 20" OF VACUUM.

MONITOR VACUUM FOR ONE MINUTE. DOES VACUUM DROP BELOW 8" OF VACUUM? NO

YES

ISOLATE VACUUM LEAK AND REPAIR OR REPLACE AS NECESSARY.*

TURN IGNITION OFF. LET ENGINE COOL.

NOTE: IS NO UP ON THE

ENSURE THERE CARBON BUILD OR IN ANY OF FOLLOWING ITEMS.

INTAKE AIR TEMP SENSOR, EGR TUBE, INTAKE AND EXHAUST MANIFOLDS.

REPAIR OR REPLACE AS NECESSARY.* RETEST EGR SYSTEM.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
485

T TEST TC-140A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - EGR SYSTEM FAILURE

FIG. 1

FIG. 2
486

TEST TC-140A CONTINUED - REPAIRING - EGR SYSTEM FAILURE

T R O U B L E C O D E
YES REPLACE INTAKE AIR TEMPERATURE SENSOR.*

TEST TC-140A CONTINUED FROM THE REVIOUSE PAGE.

TURN IGNITION OFF. REMOVE THE INTAKE AIR TEMP SENSOR AND INSPECT SENSOR FOR HEAVY SOOTING.

DOES THE INTAKE AIR TEMPERATURE SENSOR HAVE A HEAVY SOOT ACCUMULATION? NO

T E S T S

REINSTALL INTAKE AIR TEMP SENSOR.

DISCONNECT THE EGR SOLENOID CONNECTOR.**

URN IGNITION ON.

USING A VOLTMETER, MEASURE THE VOLTAGE TO THE EGR SOLENOID AT THE CONNECTOR.

IS THE VOLTAGE GREATER THAN 11.0 VOLTS?

NO

REPLACE THE EGR VALVE.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
487

T TEST TC-141A REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

488

TEST TC-141A REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI
Perform TEST DTC Before Proceeding

START TEST TC-141A.

CHECK FOR AND RECORD OTHER TRANSMISSION CODES.

ARE THERE OTHER TRANSMISSION CODES?

YES

PERFORM APPROPRIATE DTC TEST.

T R O U B L E C O D E T E S T S

NO

NOTE: YOU MAY BE REMOVING THE TRANS CONTROL RELAY DURING THIS TEST...

THIS WILL SET OTHER CODES. THEY CAN BE DISREGARDED.

START ENGINE.

WARM ENGINE TO NORMAL OPERATING TEMPERATURE.

APPLY THE PARKING BRAKE.

APPLY BRAKES. WITH THE DRB, READ THE GOVERNOR PRESSURE SENSOR. PLACE GEAR SELECT LEVER IN DRIVE. IS THE GOVERNOR PRESSURE ABOVE 3 PSI? YES PERFORM TEST TC-141B.

NO

PUT GEAR SELECT LEVER IN PARK. WITH ENGINE STILL RUNNING, REMOVE THE TRANS CONTROL RELAY.

APPLY BRAKES. PLACE GEAR SELECT LEVER IN DRIVE. IS THE GOVERNOR PRESSURE BETWEEN 40 AND 55 PSI? NO PERFORM TEST TC-141C.

YES

CONTINUE TEST 141A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
489

T TEST TC-141A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI

FIG. 1

FIG. 2
490

- REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 TEST TC-141A CONTINUED PSI

TEST TC-141A CONTINUED FROM THE PREVIOUS PAGE.

TURN ENGINE OFF. INSTALL THE TRANS CONTROL RELAY.

WHILE MONITORING TARGET GOVERNOR PRESSURE AND ACTUAL GOVERNOR PRESSURE WITH THE DRB...

T R O U B L E C O D E

DRIVE VEHICLE AT A CONSTANT SPEED BETWEEN 25 AND 30 MPH.

NOTE: ACTUAL GOVERNOR PRESSURE SHOULD BE WITHIN 5 PSI OF TARGET WITHIN 3 SECONDS.

IS ACTUAL GOVERNOR PRESSURE WITHIN 5 PSI OF TARGET GOVERNOR PRESSURE?

THE CONDITIONS YES REQUIRED TO SET THIS CODE ARE NOT PRESENT AT THIS TIME. FIG. 1 AND 2

NO

T E S T S

TEST COMPLETE.

REPLACE THE GOVERNOR PRESSURE SOLENOID.

WHILE MONITORING TARGET GOVERNOR PRESSURE AND ACTUAL GOVERNOR PRESSURE...

DRIVE VEHICLE AT A CONSTANT SPEED BETWEEN 25 AND 30 MPH.

NOTE: ACTUAL GOVERNOR PRESSURE SHOULD BE WITHIN 5 PSI OF TARGET WITHIN 3 SECONDS.

IS ACTUAL GOVERNOR PRESSURE WITHIN 5 PSI OF TARGET GOVERNOR PRESSURE?

NO

REPAIR INTERNAL TRANSMISSION LEAKAGE PROBLEM.*

YES

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
491

T TEST TC-141B REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI R O Perform TEST TC-141A Before Proceeding U B L E C O D E T E S T S

FIG. 1

492

TEST TC-141B REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI
Perform TEST TC-141A Before Proceeding

START TEST TC-141B.

KEY OFF. INSTALL A PRESSURE GAUGE AT THE GOVERNOR TEST PORT. FIG. 1

T R O U B L E C O D E

START ENGINE. READ THE GAUGE PRESSURE IN DRIVE.

IS THE GAUGE PRESSURE BELOW 5 PSI?

YES

PERFORM TEST TC-141D

NO

T E S T S

TURN ENGINE OFF.

DRAIN AND REMOVE THE TRANS OIL PAN.

CHECK FOR BURNT TRANSMISSION FLUID OR DEBRIS.

WAS FLUID BURNT AND/OR DEBRIS IN PAN?

YES

OVERHAUL THE TRANSMISSION AS NECESSARY.*

NO

REPLACE GOVERNOR PRESSURE SOLENOID PER SERVICE MANUAL.

START ENGINE. READ THE GAUGE PRESSURE IN DRIVE.

IS GAUGE PRESSURE BELOW 5 PSI?

YES TEST COMPLETE.*

NO

REPLACE THE VALVE BODY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
493

T TEST TC-141C REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI R O Perform TEST TC-141A Before Proceeding U B L E C O D E T E S T S

FIG. 1

494

TEST TC-141C REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI
Perform TEST TC-141A Before Proceeding

START TEST TC-141C.

TURN IGNITION OFF. INSTALL THE TRANS RELAY.

T R O U B L E C O D E

INSTALL A PRESSURE GAUGE AT GOVERNOR TEST PORT. FIG. 1

START ENGINE. REMOVE THE TRANS CONTROL RELAY.

T E S T S

READ THE GAUGE PRESSURE IN DRIVE.

IS THE GAUGE PRESSURE BETWEEN 40 AND 55 PSI?

YES

PERFORM TEST TC-141D.

NO

TURN ENGINE OFF. INSTALL THE TRANS RELAY. DRAIN AND REMOVE THE TRANS OIL PAN.

CHECK FOR BURNT TRANSMISSION FLUID OR DEBRIS.

WAS FLUID BURNT AND/OR DEBRIS IN PAN?

YES

OVERHAUL THE TRANSMISSION AS NECESSARY.*

NO

REPLACE THE GOVERNOR PRESSURE SOLENOID PER SERVICE MANUAL.

START ENGINE. REMOVE THE TRANS RELAY. READ THE GAUGE PRESSURE IN DRIVE.

IS THE GAUGE PRESSURE BETWEEN 40 AND 55 PSI?

YES TEST COMPLETE.*

NO

REPLACE THE VALVE BODY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
495

T TEST TC-141D REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI R O Perform TEST TC-141A Before Proceeding U AB BODY AN BODY B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
496

FIG. 4

TEST TC-141D REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI
Perform TEST TC-141A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-141D.

DISCONNECT THE SOLENOID PACK CONNECTOR.** SEE GENERAL INFO 4.2

KEY ON. MEASURE THE VOLTAGE AT THE 5-VOLT SUPPLY CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 4.5 VOLTS?

NO

REPAIR OPEN 5-VOLT SUPPLY CIRCUIT TO SOLENOID PACK CONNECTOR.*

YES

REPLACE THE GOVERNOR PRESSURE SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
497

T TEST TC-142A REPAIRING - GOVERNOR PRESSURE ABOVE 3 PSI IN GEAR WITH 0 MPH R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

498

TEST TC-142A REPAIRING - GOVERNOR PRESSURE ABOVE 3 PSI IN GEAR WITH 0 MPH
Perform TEST DTC Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-142A.

CHECK FOR OTHER TRANSMISSION CODES.

ARE THERE OTHER TRANSMISSION CODES?

YES

PERFORM APPROPRIATE "DTC TEST".

NO

ERASE ALL TROUBLE CODES.

START ENGINE.

WARM THE ENGINE TO NORMAL OPERATING TEMPERATURE.

WITH THE DRB, READ THE GOVERNOR PRESSURE SENSOR.

PLACE GEAR SELECT LEVER IN DRIVE.

IS THE GOVERNOR PRESSURE ABOVE 3 PSI?

YES

PERFORM TEST TC-142B.

NO

CONTINUE TEST TC-142A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
499

T TEST TC-142A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE ABOVE 3 PSI IN GEAR WITH 0 MPH

FIG. 1

FIG. 2
500

- REPAIRING - GOVERNOR PRESSURE ABOVE 3 PSI IN GEAR WITH 0 TEST TC-142A CONTINUED MPH

TEST TC-142A CONTINUED FROM THE PREVIOUS PAGE.

WHILE MONITORING TARGET GOVERNOR PRESSURE AND ACTUAL GOVERNOR PRESSURE...

T R O U B L E C O D E

DRIVE VEHICLE AT A CONSTANT SPEED BETWEEN 25 AND 30 MPH.

NOTE: ACTUAL GOVERNOR PRESSURE SHOULD BE WITHIN 5 PSI OF TARGET WITHIN 3 SECONDS.

IS ACTUAL GOVERNOR PRESSURE WITHIN 5 PSI OF TARGET GOVERNOR PRESSURE?

THE CONDITIONS YES REQUIRED TO SET THIS CODE ARE NOT PRESENT AT THIS TIME. FIG. 1 AND 2

NO

T E S T S

TEST COMPLETE.

REPLACE GOVERNOR PRESSURE SOLENOID.

WHILE MONITORING TARGET GOVERNOR PRESSURE AND ACTUAL GOVERNOR PRESSURE...

DRIVE VEHICLE AT A CONSTANT SPEED BETWEEN 25 AND 30 MPH.

NOTE: ACTUAL GOVERNOR PRESSURE SHOULD BE WITHIN 5 PSI OF TARGET WITHIN 3 SECONDS.

IS ACTUAL GOVERNOR PRESSURE WITHIN 5 PSI OF TARGET GOVERNOR PRESSURE?

NO

REPAIR THE INTERNAL TRANSMISSION LEAKAGE PROBLEM.*

YES

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
501

T TEST TC-142B REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI R O Perform TEST TC-142A Before Proceeding U B L E C O D E T E S T S

FIG. 1

502

TEST TC-142B REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI
Perform TEST TC-142A Before Proceeding

START TEST TC-142B.

KEY OFF. INSTALL A PRESSURE GAUGE AT GOVERNOR TEST PORT. FIG. 1

T R O U B L E C O D E T E S T S

START ENGINE. READ THE GAUGE PRESSURE IN DRIVE.

IS THE GAUGE PRESSURE BELOW 3 PSI?

YES

CONTINUE TEST 142B ON THE NEXT PAGE.

NO

TURN ENGINE OFF. DRAIN AND REMOVE THE TRANS OIL.

CHECK FOR BURNT TRANSMISSION FLUID OR DEBRIS.

WAS FLUID BURNT AND/OR DEBRIS IN PAN?

YES

OVERHAUL THE TRANSMISSION AS NECESSARY.*

NO

REPLACE THE GOVERNOR PRESSURE SOLENOID PER SERVICE MANUAL.

START ENGINE. READ THE GAUGE PRESSURE IN DRIVE.

IS GAUGE PRESSURE BELOW 3 PSI?

YES TEST COMPLETE.*

NO

REPLACE THE VALVE BODY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
503

T TEST TC-142B R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 PSI
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
504

FIG. 4

- REPAIRING - GOVERNOR PRESSURE NOT EQUAL TO TARGET 15-20 TEST TC-142B CONTINUED PSI

T R O U B L E C O D E T E S T S

TEST TC-142B CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE SOLENOID PACK CONNECTOR.**

KEY ON. MEASURE THE VOLTAGE AT THE 5-VOLT SUPPLY CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 4.5 VOLTS?

NO

REPAIR THE OPEN 5-VOLT SUPPLY CIRCUIT TO SOLENOID PACK CONNECTOR.*

YES

REPLACE THE GOVERNOR PRESSURE SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
505

T TEST TC-144A REPAIRING - 1/3 O2 SENSOR SHORTED TO GROUND R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S
FIG. 1
8.0L CAL/MD

506

TEST TC-144A REPAIRING - 1/3 O2 SENSOR SHORTED TO GROUND
Perform TEST DTC Before Proceeding

START TEST TC-144A.

REFER TO THE FIGURE FOR POSSIBLE TROUBLE CODE CAUSES. FIG. 1

T R O U B L E C O D E T E S T S

IF ENGINE IS WARM, TURN ENGINE OFF FOR 15 MINUTES TO ALLOW O2 SENSOR TO COOL DOWN.

TURN IGNITION ON. (ENGINE OFF)

WITH THE DRB, MONITOR THE 1/3 O2 SENSOR VOLTAGE.

IS THE 1/3 O2 SENSOR VOLTAGE BELOW 0.16V?

YES

CONTINUE TEST TC-144A ON THE NEXT PAGE.

NO

NOTE: A SHORTED LOW CONDITION DUE TO WATER IN THE SENSOR CONNECTOR, MAY BE TEMPORARY.

WIGGLE THE 1/3 O2 SENSOR HARNESS AND MONITOR THE VOLTAGE.

DID THE 1/3 O2 SENSOR VOLTAGE CHANGE WHILE WIGGLING THE HARNESS? YES

NO

THE CONDITION REQUIRED TO SET THIS TROUBLE CODE IS NOT PRESENT AT THIS TIME.*

REPAIR THE HARNESS OR WIRING THAT HAS THE INTERMITTENT SHORT TO GROUND.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
507

T TEST TC-144A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 1/3 O2 SENSOR SHORTED TO GROUND

FIG. 1
508

TEST TC-144A CONTINUED - REPAIRING - 1/3 O2 SENSOR SHORTED TO GROUND

CONTINUE TEST TC-144A FROM THE PREVIOUS PAGE.

DISCONNECT THE 1/3 O2 SENSOR.** SEE GENERAL INFO 4.4

IS THE TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

T R O U B L E C O D E

NO

WITH THE DRB, READ THE 1/3 O2 SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 0.16 VOLTS?

NO

REPLACE THE 1/3 O2 SENSOR.*

YES

T E S T S

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTORS.** SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

USING AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE 1/3 02 SENSOR SIGNAL CIRCUIT FROM THE PCM CONNECTOR TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE 1/3 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

WIGGLE THE O2 SENSOR HARNESS WHILE CHECKING RESISTANCE OF O2 SENSOR SIGNAL CIRCUIT.

DID THE RESISTANCE CHANGE WHILE WIGGLING THE HARNESS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE 1/3 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
509

T TEST TC-147A REPAIRING - 1/3 O2 SENSOR SHORTED TO VOLTAGE R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

510

TEST TC-147A REPAIRING - 1/3 O2 SENSOR SHORTED TO VOLTAGE
Perform TEST DTC Before Proceeding

START TEST TC-147A.

WARM UP ENGINE TO ABOVE 180F, WAIT 4 MINUTES, LEAVE ENGINE RUNNING.

T R O U B L E C O D E T E S T S

WITH THE DRB, READ THE 1/3 O2 SENSOR VOLTAGE.

IS THE 1/3 O2 SENSOR VOLTAGE ABOVE 1.5 VOLTS?

YES

CONTINUE TEST TC-147A ON THE NEXT PAGE.

NO

WIGGLE THE 1/3 O2 SENSOR CONNECTOR AND HARNESS. SEE GENERAL INFO 4.4

WHILE WIGGLING THE HARNESS, WATCH THE DRB DISPLAY.

DID THE 1/3 O2 SENSOR VOLTAGE GO ABOVE 1.5 VOLTS AT ANY TIME?

YES

REPAIR THE HARNESS OR CONNECTOR THAT HAS THE INTERMITTENT OPEN CIRCUIT OR SHORT TO VOLTAGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE THERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
511

T TEST TC-147A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 1/3 O2 SENSOR SHORTED TO VOLTAGE

FIG. 1
512

TEST TC-147A CONTINUED - REPAIRING - 1/3 O2 SENSOR SHORTED TO VOLTAGE

TEST TC-147A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE 1/3 O2 SENSOR.** SEE GENERAL INFO 4.4

IS THE TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

T R O U B L E C O D E

NO

WITH THE DRB, READ THE 1/3 O2 SENSOR VOLTAGE.

IS THE VOLTAGE ABOVE 4.97 VOLTS?

NO

REPLACE THE 1/3 O2 SENSOR.*

YES

T E S T S

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTORS.** SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

TURN IGNITION ON. USING A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE 1/3 02 SENSOR SIGNAL CIRCUIT AT THE PCM CONNECTOR. FIG. 1

IS THE VOLTAGE ABOVE 5.0 VOLTS?

YES

REPAIR THE 1/3 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE.*

NO

WIGGLE THE O2 SENSOR HARNESS WHILE CHECKING FOR VOLTAGE IN THE O2 SENSOR SIGNAL CIRCUIT.

DID THE VOLTAGE CHANGE WHILE WIGGLING THE HARNESS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE 1/3 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
513

T TEST TC-148A REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

ALL BODIES WITH 3SPD RH TRANS

ALL OTHERS

514

TEST TC-148A REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP
Perform TEST DTC Before Proceeding

START TEST TC-148A.

WITH THE DRB, READ THE TROUBLE CODES.

IS THE "THROTTLE POSITION SENSOR VOLTAGE TOO LOW" CODE SET?

YES

PERFORM TEST TC-26A.

T R O U B L E C O D E

NO

IS THE "THROTTLE POSITION SENSOR VOLTAGE TOO HIGH" CODE SET?

YES

PERFORM TEST TC-27A.

NO

T E S T S

IS THE "PCM FAILURE EEPROM WRITE DENIED" CODE SET?

YES

PERFORM TEST TC-49A.

NO

IS THE "TORQUE CONVERTER CLUTCH SOLENOID TROUBLE" CODE PRESENT?

YES

PERFORM TEST TC-12A.

NO

ARE ANY "MISFIRE TROUBLE" CODES SET?

YES

PERFORM APPROPRIATE MISFIRE DTC TEST.

NO

IS THE "NO CRANK REFERENCE SIGNAL AT PCM" TROUBLE CODE PRESENT?

YES

PERFORM TEST TC-40A.

NO

CONTINUE TEST TC-148A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
515

T TEST TC-148A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP

FIG. 1
ALL BODIES WITH 3 SPD RH TRANS ALL OTHERS

516

TEST TC-148A CONTINUED - REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP

TEST TC-148A CONTINUED FROM THE PREVIOUS PAGE.

CHECK TRANSMISSION FLUID LEVEL AND FOR ANY DEBRIS.

IS FLUID LEVEL OK AND CLEAR FROM CONTAMINATION?

NO

REPAIR AS NECESSARY.*

T R O U B L E C O D E

YES

IS THIS AN AB BODY WITH A 3 SPEED RH TRANSMISSION?

YES

PERFORM TEST TC-148C.

NO

T E S T S

WITH THE DRB, PERFORM THE TCC SYSTEM TEST.

DID THE VEHICLE STALL?

NO

CONTINUE TEST TC-148A ON THE NEXT PAGE.

YES

START VEHICLE.

PERFORM THE GOV AND 3-4 SHIFT VALVE SYSTEM TEST. SELECT 4TH GEAR.

DID THE VEHICLE STALL?

YES

PERFORM TEST TC-148B.

NO

REMOVE THE OIL PAN AND INSPECT FOR EXCESSIVE DEBRIS.

DOES PAN CONTAIN EXCESSIVE DEBRIS?

YES

REPAIR THE INTERNAL TRANSMISSION PROBLEM.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE THERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
517

T TEST TC-148A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP

NOTES

518

TEST TC-148A CONTINUED - REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP

T R O U B L E C O D E T E S T S

TEST TC-148A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF. CONNECT A PRESSURE GAUGE TO THE TRANSMISSION COOLER OUT PORT WITH A "T" CONNECTOR.

START ENGINE.

WITH THE DRB, PERFORM THE TCC SYSTEM TEST.

DID THE COOLER OUT PRESSURE INCREASE WHEN THE TCC WAS ACTUATED?

YES

REPLACE THE TORQUE CONVERTER.*

NO

REPAIR VALVE BODY PER SERVICE MANUAL. CHECK FOR BLOCKAGE OR LEAKS IN THE TCC HYDRAULIC CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
519

T TEST TC-148B REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP R O Perform TEST TC-148A Before Proceeding U B L E C O D E T E S T S

START TEST TC-148B.

REPLACE THE TCC SOLENOID.

PERFORM THE GOV AND 3-4 SHIFT VALVE SYSTEM TEST. SELECT 4TH GEAR.

DID THE VEHICLE STALL?

NO TEST COMPLETE.*

YES

REPAIR THE INTERNAL PROBLEM. CHECK FOR BLOCKED PASSAGE(S).*

520

TEST TC-148C REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP
Perform TEST TC-148A Before Proceeding

START TEST TC-148C.

ROAD TEST VEHICLE WHILE MONITORING TCC STATE AND ENGINE RPM WITH THE DRB.

DOES THE ENGINE RPM DROP WHEN THE TCC STATE GOES TO ON?

YES

AT THIS TIME, THE CONDITIONS REQUIRED TO SET THIS CODE ARE NOT PRESENT.

T R O U B L E C O D E T E S T S

NO

TEST COMPLETE.

REMOVE OIL PAN AND CHECK FOR DEBRIS OR BURNT OIL.

DOES THE PAN CONTAIN EXCESSIVE DEBRIS AND/OR IS THE FLUID BURNT?

YES

REPAIR THE INTERNAL TRANSMISSION PROBLEM.*

NO

REPLACE THE TCC SOLENOID.

WITH THE DRB, CLEAR CODES.

ROAD TEST VEHICLE WHILE MONITORING THROTTLE ANGLE WITH THE DRB.

ACCELERATE VEHICLE TO 60 MPH MAINTAINING A CONSTANT 20 DEGREE THROTTLE ANGLE.

REPEAT PRECEEDING TEST 4 TIMES.

WITH THE DRB, READ DTC’S.

DID THE CODE RETURN DURING THE ROAD TEST?

NO TEST COMPLETE.*

YES

REPLACE THE TORQUE CONVERTER.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
521

T TEST TC-148C R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP

NOTES

522

TEST TC-148C CONTINUED - REPAIRING - TORQ CONV CLU, NO RPM DROP AT LOCKUP

T R O U B L E C O D E T E S T S

TEST TC-148C CONTINUED FROM THE PREVIOUS PAGE.

REMOVE THE OIL PAN AND INSPECT FOR EXCESSIVE DEBRIS AND BURNT OIL.

IS THE OIL BURNT OR DOES THE PAN CONTAIN EXCESSIVE DEBRIS?

YES

REPAIR THE INTERNAL TRANSMISSION PROBLEM.*

NO

AT THIS TIME, THE CONDITIONS REQUIRED TO SET THIS CODE ARE NOT PRESENT.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
523

T TEST TC-149A REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO LOW R O Perform TEST DTC Before Proceeding U AB BODY XJ BODY B L E C O D E T E S T S

ZJ BODY

FIG. 1
524

TEST TC-149A REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO LOW
Perform TEST DTC Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-149A.

WITH THE DRB, READ THE FUEL LEVEL SENDING UNIT VOLTAGE.

IS THE FUEL LEVEL SENDING UNIT VOLTAGE BELOW 0.2 VOLT?

YES

CONTINUE TEST TC-149A ON THE NEXT PAGE.

NO

USING THE SCHEMATIC, WIGGLE THE FUEL PUMP MODULE CONNECTOR & HARNESS.

MONITOR THE DRB DISPLAY.

WAS THERE ANY FUEL LEVEL SENDING UNIT SENSOR VOLTAGE CHANGE?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
525

T TEST TC-149A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO LOW

FIG. 1
XJ BODY

FIG. 2
ZJ BODY

FIG. 3
526

TEST TC-149A CONTINUED - REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO LOW

TEST TC-149A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE FUEL PUMP MODULE CONNECTOR.** SEE GENERAL INFO 4.0

T R O U B L E C O D E

WITH THE DRB, READ THE FUEL LEVEL SENDING UNIT VOLTAGE.

IS THE FUEL LEVEL SENDING UNIT VOLTAGE ABOVE 4.5 VOLTS?

YES

REPLACE THE FUEL PUMP MODULE.*

NO

T E S T S

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE FUEL LEVEL SENSOR SIGNAL CIRCUIT (OBDII) TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

WITH AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE...

FUEL LEVEL SENSOR SIGNAL CIRCUIT (OBDII) AND THE SENSOR GROUND CKT. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

REPAIR THE FUEL YES LEVEL SENSOR SIGNAL CIRCUIT SHORTED TO THE SENSOR GROUND CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
527

T TEST TC-150A REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO HIGH R O Perform TEST DTC Before Proceeding U AB BODY XJ BODY B L E C O D E T E S T S

ZJ BODY

FIG. 1
528

TEST TC-150A REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO HIGH
Perform TEST DTC Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-150A.

WITH THE DRB, READ THE FUEL LEVEL SENDING UNIT VOLTAGE.

IS THE FUEL LEVEL SENDING UNIT VOLTAGE ABOVE 4.7 VOLTS?

YES

CONTINUE TEST TC-150A ON THE NEXT PAGE.

NO

USE THE SCHEMATIC AS A GUIDE AND WIGGLE THE FUEL PUMP MODULE CONNECTOR & HARNESS.

MONITOR THE DRB DISPLAY.

WAS THERE ANY FUEL LEVEL SENDING UNIT VOLTAGE CHANGE?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
529

T TEST TC-150A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO HIGH

FIG. 1
XJ BODY

FIG. 2
ZJ BODY

FIG. 3
530

TEST TC-150A CONTINUED - REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO HIGH

TEST TC-150A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE FUEL PUMP MODULE CONNECTOR.** SEE GENERAL INFO 4.4

T R O U B L E C O D E T E S T S

WITH A VOLTMETER, MEASURE THE FUEL LEVEL SIGNAL CIRCUIT FOR VOLTAGE. FIG. 1, 2 OR 3

IS THE VOLTAGE AVOVE 5.5 VOLTS?

YES

REPAIR THE FUEL LEVEL SIGNAL CIRCUIT SHORTED TO VOLTAGE.*

NO

CONNECT A JUMPER BETWEEN FUEL LEVEL SIGNAL (OBDII) AND SENSOR GND CKT. FIG. 1, 2 OR 3

WITH THE DRB, READ THE FUEL LEVEL SENDING UNIT VOLTAGE.

IS THE VOLTAGE BELOW 1.0 VOLT?

YES

REPLACE THE FUEL PUMP MODULE.*

NO

MOVE THE JUMPER WIRE FROM THE SENSOR GROUND TO A KNOWN GOOD GROUND. FIG. 1, 2 OR 3

WITH THE DRB, READ THE FUEL LEVEL SENDING UNIT VOLTAGE.

IS THE VOLTAGE BELOW 1.0 VOLT?

YES

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

NO

CONTINUE TEST TC-150A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
531

T TEST TC-150A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO HIGH

FIG. 1
XJ BODY

FIG. 2
ZJ BODY

FIG. 3
532

TEST TC-150A CONTINUED - REPAIRING - FUEL LEVEL SENDING UNIT VOLTS TOO HIGH

T R O U B L E C O D E T E S T S

TEST TC-150A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

USING AN OHMMETER, MEASURE THE FUEL LEVEL SENSOR SIGNAL CIRCUIT (OBD II)... FIG. 1, 2 OR 3

FROM THE PCM TO THE FUEL PUMP MODULE CONNECTOR.

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN FUEL LEVEL SENSOR SIGNAL CIRCUIT (OBDII).*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
533

T TEST TC-151A REPAIRING - FUEL LEVEL UNIT NO CHANGE OVER MILES R O Perform TEST DTC Before Proceeding U AB BODY XJ BODY B L E C O D E T E S T S

ZJ BODY

FIG. 1
534

TEST TC-151A REPAIRING - FUEL LEVEL UNIT NO CHANGE OVER MILES
Perform TEST DTC Before Proceeding

START TEST TC-151A.

WITH THE DRB, READ THE FUEL LEVEL SENDING UNIT VOLTAGE AND MAKE A NOTE OF VOLTAGE.

IS THE FUEL LEVEL SENDING UNIT VOLTAGE BELOW 0.2 VOLT?

YES

PERFORM TEST TC-149A.

T R O U B L E C O D E

NO

IS THE FUEL LEVEL SENDING UNIT VOLTAGE ABOVE 4.7 VOLTS?

YES

PERFORM TEST TC-150A.

NO

T E S T S

IS THE FUEL LEVEL SENDING UNIT VOLTAGE BETWEEN 2.5 AND 4.7 VOLTS?

NO

CONTINUE TEST TC-151A ON THE NEXT PAGE.

YES

ADD FIVE GALLONS OF FUEL TO FUEL TANK.

WITH THE DRB, READ THE FUEL LEVEL SENDING UNIT VOLTAGE.

DID THE FUEL LEVEL SENDING UNIT VOLTAGE DECREASE BY AT LEAST 0.2 VOLTS? YES

NO

REPLACE FUEL PUMP MODULE.*

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
535

T TEST TC-151A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - FUEL LEVEL UNIT NO CHANGE OVER MILES
ZJ BODY

XJ BODY

FIG. 1
536

TEST TC-151A CONTINUED - REPAIRING - FUEL LEVEL UNIT NO CHANGE OVER MILES

TEST TC-151A CONTINUED FROM PREVIOUS PAGE.

IS THE VEHICLE A "ZJ" BODY WITH A CALIFORNIA EMISSION PACKAGE?

T R O U B L E C O D E T E S T S

NO

YES

IS THE FUEL LEVEL SENDING UNIT VOLTAGE BETWEEN 0.2 AND 1.0 VOLTS?

NO

AT THIS TIME THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. TEST COMPLETE.

YES

REMOVE AT LEAST FIVE GALLONS OF FUEL FROM TANK.

WITH THE DRB, READ THE FUEL LEVEL SENDING UNIT VOLTAGE.

DID THE FUEL LEVEL SENDING UNIT VOLTAGE INCREASE BY AT LEAST O.2 VOLTS? YES

NO

REPLACE THE FUEL PUMP MODULE.*

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

NO TEST COMPLETE.*

YES

REPAIR AS NECESSARY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
537

T TEST TC-153A REPAIRING - BATTERY TEMP SENSOR VOLTAGE TOO LOW/TOO HIGH R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
538

TEST TC-153A REPAIRING - BATTERY TEMP SENSOR VOLTAGE TOO LOW/TOO HIGH
Perform TEST DTC Before Proceeding

START TEST TC-153A.

WITH THE DRB, READ THE BATTERY TEMPERATURE SENSOR (BTS) VOLTAGE.

T R O U B L E C O D E T E S T S

IS THE BTS VOLTAGE BELOW 0.4 VOLT?

YES

CONTINUE TEST TC-153A ON THE NEXT PAGE.

NO

IS THE BTS VOLTAGE ABOVE 4.9 VOLTS?

YES

PERFORM TEST TC-153B.

NO

USE THE SCHEMATIC AS A GUIDE AND WIGGLE THE BTS CONNECTOR AND HARNESS.

MONITOR THE DRB DISPLAY.

WAS THERE ANY BTS VOLTAGE CHANGE?

YES

REPAIR THE CONNECTOR OR HARNESS THAT CAUSED THE VOLTAGE CHANGE.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE CONNECTORS AND HARNESS WIRING.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
539

T TEST TC-153A CONTINUED - REPAIRING - BATTERY TEMP SENSOR VOLTAGE TOO LOW R O U AB, AN AND BR BODIES B L E C O D E T E S T S
FIG. 1
XJ BODY

FIG. 2
ZJ BODY

FIG. 3
540

TEST TC-153A CONTINUED - REPAIRING - BATTERY TEMP SENSOR VOLTAGE TOO LOW

TEST TC-153A CONTINUED FROM PREVIOUS PAGE.

DISCONNECT THE BATTERY TEMPERATURE SENSOR (BTS). SEE GENERAL INFO 4.4

T R O U B L E C O D E T E S T S

WITH THE DRB, READ THE BTS VOLTAGE.

IS THE BTS VOLTAGE ABOVE 4.0 VOLTS?

YES REPLACE THE BTS.*

NO

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE BTS SIGNAL CIRCUIT TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE BTS SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

WITH AN OHMMETER, MEASURE THE BTS SIGNAL CIRCUIT TO SENSOR GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE SENSOR SIGNAL SHORTED TO SENSOR GROUND.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
541

T TEST TC-153B REPAIRING - BATTERY TEMP SENSOR VOLTAGE TOO HIGH R O Perform TEST TC-153A Before Proceeding U AB, AN AND BR BODIES XJ BODY B L E C O D E T E S T S
FIG. 1
ZJ BODY

FIG. 2
AB, AN AND BR BODIES

FIG. 3
XJ BODY ZJ BODY

FIG. 4

FIG. 5
542

FIG. 6

TEST TC-153B REPAIRING - BATTERY TEMP SENSOR VOLTAGE TOO HIGH
Perform TEST TC-153A Before Proceeding

START TEST TC-153B.

DISCONNECT THE BATTERY TEMPERATURE SENSOR (BTS).** SEE GENERAL INFO 4.4

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE VOLTAGE OF THE SENSOR GROUND CIRCUIT. FIG. 1, 2 OR 3

IS THE VOLTAGE BELOW 0.2 VOLT?

YES

REPAIR THE SENSOR GROUND CIRCUIT SHORTED TO VOLTAGE.*

NO

T E S T S

CONNECT A JUMPER ACROSS THE SENSOR SIGNAL AND THE SENSOR GROUND. FIG. 1, 2 OR 3

WITH THE DRB, READ THE BTS VOLTAGE.

IS THE BTS VOLTAGE BELOW 1.0 VOLT?

YES REPLACE THE BTS.*

NO

MOVE THE JUMPER WIRE FROM THE SENSOR GROUND TO AN ENGINE GROUND. FIG. 1, 2 OR 3

WITH THE DRB, READ THE BTS VOLTAGE.

IS THE VOLTAGE BELOW 1.0 VOLT?

YES

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

NO

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

WITH AN OHMMETER, MEASURE THE BTS SIGNAL CIRCUIT FROM...

THE PCM TO THE BTS CONNECTOR. FIG. 4, 5 OR 6

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN BATTERY TEMP SENSOR SIGNAL CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
543

T TEST TC-155A REPAIRING - 1/1 O2 SENSOR SHORTED TO GROUND R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

544

TEST TC-155A REPAIRING - 1/1 O2 SENSOR SHORTED TO GROUND
Perform TEST DTC Before Proceeding

START TEST TC-155A.

REFER TO FIGURE 1 FOR POSSIBLE TROUBLE CODE CAUSES.

T R O U B L E C O D E T E S T S

IF ENGINE IS WARM, TURN ENGINE OFF FOR 15 MINUTES TO ALLOW O2 SENSOR TO COOL DOWN.

TURN INGITION ON. (ENGINE OFF)

WITH THE DRB, MONITOR THE 1/1 O2 SENSOR VOLTAGE.

IS THE 1/1 O2 SENSOR VOLTAGE BELOW 0.16 VOLT?

YES

CONTINUE TEST TC-155A ON THE NEXT PAGE.

NO

NOTE: A SHORTED LOW CONDITION DUE TO WATER IN THE SENSOR CONNECTOR, MAY BE TEMPORARY.

WIGGLE THE 1/1 O2 SENSOR HARNESS AND MONITOR THE VOLTAGE.

DID THE 1/1 O2 SENSOR VOLTAGE CHANGE WHILE WIGGLING WIRE?

NO

THE CONDITION REQUIRED TO SET THIS TROUBLE CODE IS NOT PRESENT AT THIS TIME.*

YES

REPAIR THE HARNESS OR WIRING THAT HAS THE INTERMITTENT SHORT TO GROUND.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
545

T TEST TC-155A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 1/1 O2 SENSOR SHORTED TO GROUND

FIG. 1

546

TEST TC-155A CONTINUED - REPAIRING - 1/1 O2 SENSOR SHORTED TO GROUND

CONTINUE TEST TC-155A FROM THE PREVIOUS PAGE.

DISCONNECT THE 1/1 O2 SENSOR.** SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

T R O U B L E C O D E

NO

WITH THE DRB, READ THE 1/1 O2 SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 0.16 VOLTS?

NO

REPLACE THE 1/1 O2 SENSOR.*

YES

T E S T S

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTORS.** SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

USING AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE 1/1 02 SENSOR SIGNAL CIRCUIT FROM THE PCM CONNECTOR TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE 1/1 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

WIGGLE THE O2 SENSOR HARNESS WHILE CHECKING RESISTANCE OF O2 SENSOR SIGNAL CIRCUIT.

DID THE RESISTANCE CHANGE WHILE WIGGLING THE HARNESS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE 1/1 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
547

T TEST TC-156A REPAIRING - 1/2 O2 SENSOR SHORTED TO GROUND R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

548

TEST TC-156A REPAIRING - 1/2 O2 SENSOR SHORTED TO GROUND
Perform TEST DTC Before Proceeding

START TEST TC-156A.

REFER TO THE FIGURE FOR POSSIBLE TROUBLE CODE CAUSES. FIG. 1

T R O U B L E C O D E T E S T S

IF ENGINE IS WARM, TURN ENGINE OFF FOR 15 MINUTES TO ALLOW O2 SENSOR TO COOL DOWN.

TURN INGITION ON. (ENGINE OFF)

WITH THE DRB, MONITOR THE 1/2 O2 SENSOR VOLTAGE.

IS THE 1/2 O2 SENSOR VOLTAGE BELOW 0.16V?

YES

CONTINUE TEST TC-156A ON THE NEXT PAGE.

NO

NOTE: A SHORTED LOW CONDITION DUE TO WATER IN THE SENSOR CONNECTOR, MAY BE TEMPORARY.

WIGGLE THE 1/2 O2 SENSOR HARNESS AND MONITOR VOLTAGE.

DID THE 1/2 O2 SENSOR VOLTAGE CHANGE WHILE WIGGLING THE HARNESS? YES

NO

THE CONDITION REQUIRED TO SET THIS TROUBLE CODE IS NOT PRESENT AT THIS TIME.*

REPAIR THE HARNESS OR WIRING THAT HAS THE INTERMITTENT SHORT TO GROUND.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
549

T TEST TC-156A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 1/2 O2 SENSOR SHORTED TO GROUND

FIG. 1

550

TEST TC-156A CONTINUED - REPAIRING - 1/2 O2 SENSOR SHORTED TO GROUND

CONTINUE TEST TC-156A FROM THE PREVIOUS PAGE.

DISCONNECT THE 1/2 O2 SENSOR.** SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

T R O U B L E C O D E

NO

WITH THE DRB, READ THE 1/2 O2 SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 0.16 VOLTS?

NO

REPLACE THE 1/2 O2 SENSOR.*

YES

T E S T S

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTORS.** SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE 1/2 02 SENSOR SIGNAL CIRCUIT FROM THE PCM CONNECTOR TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE 1/2 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

WIGGLE THE O2 SENSOR HARNESS WHILE CHECKING RESISTANCE OF O2 SENSOR SIGNAL CIRCUIT.

DID THE RESISTANCE CHANGE WHILE WIGGLING THE HARNESS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE 1/2 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
551

T TEST TC-157A REPAIRING - INTERMITTENT LOSS OF CMP OR CKP R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

552

TEST TC-157A REPAIRING - INTERMITTENT LOSS OF CMP OR CKP
Perform TEST DTC Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-157A.

SEE FIGURE 1 FOR TROUBLE CODE INFORMATION.

IS THIS VEHICLE EQUIPPED WITH AN 8.0L ENGINE?

YES

CONTINUE TEST TC-157A ON THE NEXT PAGE.

NO

WITH DRB, CHECK THE DISTRIBUTOR POSITION WITH SET SYNC SIGNAL UNDER MISC. FUNCTIONS.

IS THE DISTRIBUTOR POSITION IN RANGE?

NO

SET DISTRIBUTOR POSITION WITH DRB USING STEPS GIVEN IN TEST NS-8A.*

YES

CONTINUE TEST TC-157A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
553

T TEST TC-157A CONTINUED - REPAIRING - INTERMITTENT LOSS OF CMP OR CKP R O U AB, AN, BR, AND XJ BODIES B L E C O D E T E S T S

FIG. 1
ZJ BODY

FIG. 2
554

TEST TC-157A CONTINUED - REPAIRING - INTERMITTENT LOSS OF CMP OR CKP

TEST TC-157A CONTINUED FROM THE PREVIOUS PAGE.

NOTE: CMP OR CKP SIGNAL LOSS CAN BE DETECTED BY A RPM CHANGE, TROUBLE CODE, OR...

T R O U B L E C O D E

A PATTERN ON THE OSCILLOSCOPE.

DO YOU WANT TO DIAGNOSE CMP OR CKP SIGNAL LOSS WITH AN OSCILLOSCOPE? YES

NO

PERFORM TEST TC-157B.

T E S T S

AT THE CMP SENSOR, BACKPROBE THE SENSOR SIGNAL CKT WITH THE VOLTAGE LEAD. FIG. 1 OR 2

START THE ENGINE AND OBSERVE THE CMP SENSOR VOLTAGE PATTERN ON THE SCOPE.

ARE THERE ANY CAMSHAFT POSITION SENSOR SIGNALS MISSING?

NO

CONTINUE TEST TC-157A ON THE NEXT PAGE.

YES

TURN THE IGNITION OFF.

DISCONNECT THE CMP SENSOR CONNECTOR. INSPECT ALL TERMINALS.** SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

DISCONNECT THE PCM BLACK CONNECTOR. INSPECT ALL TERMINALS.** SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

PERFORM TEST TC-157C.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
555

T TEST TC-157A CONTINUED - REPAIRING - INTERMITTENT LOSS OF CMP OR CKP R O U AB, AN, BR AND XJ BODIES ZJ BODY B L E C O D E T E S T S
FIG. 1
AB, AN AND BR BODIES XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
556

TEST TC-157A CONTINUED - REPAIRING - INTERMITTENT LOSS OF CMP OR CKP

TEST TC-157A CONTINUED FROM THE PREVIOUS PAGE.

AT THE PCM, BACKPROBE THE CMP SENSOR SIGNAL CKT WITH THE VOLTAGE LEAD. FIG. 1 OR 2

T R O U B L E C O D E

WHILE OBSERVING THE SCOPE PATTERN, WIGGLE THE CMP SENSOR CIRCUIT FROM THE SENSOR TO PCM.

WERE ANY SIGNALS MISSING WHEN THE WIGGLE TEST WAS CONDUCTED?

YES

REPAIR WIRING WHERE WIGGLING CAUSED A MISSING CMP SENSOR SIGNAL.*

NO

T E S T S

TURN IGNITION OFF.

AT THE CRANKSHAFT POSITION SENSOR, BACKPROBE THE CKP SENSOR SIGNAL CIRCUIT...

WITH THE SCOPE’S VOLTAGE MEASUREMENT LEAD. FIG. 3, 4 OR 5

START THE ENGINE AND OBSERVE THE CKP SENSOR VOLTAGE PATTERN ON THE SCOPE.

ARE ANY CRANKSHAFT POSITION SENSOR SIGNALS MISSING?

NO

CONTINUE TEST TC-157A ON THE NEXT PAGE.

YES

TURN IGNITION OFF.

DISCONNECT THE CKP SENSOR. INSPECT ALL TERMINALS.** SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

DISCONNECT THE PCM BLACK CONNECTOR.** INSPECT ALL TERMINALS. SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

PERFORM TEST TC-157D.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
557

T TEST TC-157A CONTINUED - REPAIRING - INTERMITTENT LOSS OF CMP OR CKP R O U AB, AN, BR AND XJ BODIES B L E C O D E T E S T S

FIG. 1
ZJ BODY

FIG. 2
558

TEST TC-157A CONTINUED - REPAIRING - INTERMITTENT LOSS OF CMP OR CKP

T R O U B L E C O D E T E S T S

TEST TC-157A CONTINUED FROM THE PREVIOUS PAGE.

AT PCM, BACKPROBE CKP SENSOR SIGNAL CKT WITH SCOPE’S VOLTAGE LEAD. FIG. 1 OR 2

WHILE OBSERVING THE SCOPE PATTERN, WIGGLE CKP SENSOR CIRCUIT FROM SENSOR TO PCM.

WERE ANY CKP SENSOR SIGNALS MISSING WHEN THE WIGGLE TEST WAS CONDUCTED? NO

YES

NOTE WHERE WIGGLING THE WIRES CAUSED A MISSING CKP SENSOR SIGNAL.

THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT.

REPAIR THE CAMSHAFT AND CRANKSHAFT WIRE HARNESS AS NECESSARY.*

REFER TO GENERAL INFO 3.3.2 FOR INFORMATION ON INACTIVE TROUBLE CODES.

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
559

T TEST TC-157B REPAIRING - INTERMITTENT LOSS OF CMP OR CKP R O Perform TEST TC-157A Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
560

TEST TC-157B REPAIRING - INTERMITTENT LOSS OF CMP OR CKP
Perform TEST TC-157A Before Proceeding

START TEST TC-157B.

KEY OFF. DISCONNECT THE PCM BLACK CONNECTOR.** INSPECT ALL TERMINALS. SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR AS NECESSARY.*

T R O U B L E C O D E

NO

DISCONNECT THE CMP SENSOR CONNECTOR.** INSPECT ALL TERMINALS. SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

T E S T S

DISCONNECT THE CKP SENSOR CONNECTOR.** INSPECT ALL TERMINALS. SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

RECONNECT THE PCM, CKP AND CMP CONNECTORS.

START THE ENGINE AND LET IT IDLE.

WITH THE DRB, MONITOR THE RPM WHILE WIGGLING CMP & CKP HARNESS WIRING.

DOES THE ENGINE SPEED CHANGE WHEN WIGGLING THE WIRE HARNESS?

YES

NOTE WHERE WIGGLING WIRES CAUSED A ENG SPEED CHANGE & REPAIR WIRE HARNESS AS NECESSARY.*

NO

YES

NO PROBLEM HAS BEEN FOUND. DO YOU WANT TO WIGGLE ANOTHER WIRE HARNESS SECTION? NO

THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT FIG.1

REFER TO FIGURE 2 FOR INACTIVE TROUBLE CODE INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
561

T TEST TC-157C REPAIRING - INTERMITTENT LOSS OF CMP OR CKP R O Perform TEST TC-157A Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
562

TEST TC-157C REPAIRING - INTERMITTENT LOSS OF CMP OR CKP
Perform TEST TC-157A Before Proceeding

START TEST TC-157C.

IS THE VEHICLE EQUIPPED WITH AN 8.0L ENGINE?

REMOVE THE CAMSHAFT YES POSITION SENSOR AND INSPECT THE CAMSHAFT SPROCKET. FIG. 1

T R O U B L E C O D E T E S T S

NO

REMOVE THE DISTRIBUTOR CAP. FIG. 2

INSPECT THE ROTOR AND ROTOR DRIVE SYSTEM FOR LOOSENESS PER SERVICE MANUAL INSTRUCTIONS.

IS THE CAMSHAFT SPROCKET OK?

YES

REPLACE THE CAMSHAFT POSITION SENSOR.*

NO

REPAIR AS NECESSARY.*

IS THE ROTOR AND ROTOR DRIVE SYSTEM OK?

NO

REPAIR THE LOOSE DISTRIBUTOR ROTOR OR ROTOR DRIVE SYSTEM AS NECESSARY.*

YES

REPLACE THE CAMSHAFT POSITION SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
563

T TEST TC-157D REPAIRING - INTERMITTENT LOSS OF CMP OR CKP R O Perform TEST TC-157A Before Proceeding U 2.5L AND 4.0L ENGINES B L E C O D E T E S T S
FIG. 1
3.9L, 5.2L AND 5.9L ENGINES

FIG. 2
8.0L ENGINES

FIG. 3
564

TEST TC-157D REPAIRING - INTERMITTENT LOSS OF CMP OR CKP
Perform TEST TC-157A Before Proceeding

START TEST TC-157D.

REMOVE THE CRANKSHAFT POSITION SENSOR. FIG. 1, 2 OR 3

WAS THE CRANKSHAFT POSITION SENSOR PROPERLY INSTALLED?

NO

REPAIR AS NECESSARY.*

T R O U B L E C O D E T E S T S

YES

NO

IS THE VEHICLE EQUIPPED WITH AN 8.0L ENGINE?

YES

INSPECT THE CRANKSHAFT NOTCHES FOR DAMAGE OR MISALIGNMENT.

IS THE CRANKSHAFT OKAY?

NO

REPAIR AS NECESSARY.*

YES

REPLACE THE CRANKSHAFT POSITION SENSOR.*

INSPECT THE FLYWHEEL FOR DAMAGE OR MISALIGNMENT.

IS THE FLYWHEEL DAMAGED?

YES

REPAIR AS NECESSARY.*

NO

REPLACE THE CRANKSHAFT POSITION SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
565

T TEST TC-160A REPAIRING - EVAP LEAK MONITOR SMALL LEAK DETECTED R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2

FIG. 3
566

FIG. 4

TEST TC-160A REPAIRING - EVAP LEAK MONITOR SMALL LEAK DETECTED
Perform TEST DTC Before Proceeding

START TEST TC-160A.

NOTE: A LOOSE GAS CAP COULD CAUSE THIS TROUBLE CODE TO SET.

NOTE: THE FUEL TANK MUST HAVE AT LEAST THREE GALLONS OF FUEL TO PERFORM THIS TEST.

WARNING: READ FIGURE 1 BEFORE CONTINUING.

T R O U B L E C O D E

CONNECT A HAND VACUUM PUMP TO LDP VACUUM TEE (SVST PORT).

WITH HAND PUMP, APPLY 18 INCHES OF VACUUM TO LEAK DETECTION PUMP (LDP).

DOES THE PUMP HOLD VACUUM?

NO

ENSURE VACUUM LINES ARE OK BEFORE REPLACING LDP. PERFORM TC-160A TO VERIFY.

YES

T E S T S

REPLACE LDP. IGNITION KEY ON. WITH THE DRB, GO TO ACTUATIONS, ACTUATE LDP. DID VACUUM DROP WHEN SOLENOID WAS ACTUATED? NO PERFORM TEST TC-160A TO VERIFY.

YES

TO CONTINUE TESTING YOU WILL NEED MILLER TOOL KIT #6872A. FIG. 2

PERFORM EVAPORATIVE SYSTEM PRESSURE PUMP SELF TEST THAT IS SPECIFIED ON THE TESTER COVER.

CONNECT THE EVAP PRESSURE PUMP SUPPLY HOSE TO VEHICLE PRESSURE TEST PORT. SEE GENERAL INFO 4.2

USING AN AUXILIARY CONSTANT VACUUM SUPPLY, DRB IN LDP SYSTEM TEST, PRESS 3 TO HOLD,...

DISCONNECT PURGE SOLENOID. SET PRESSURE HOLD TO OPEN, AND SET VENT TO CLOSED.

TURN PUMP TIMER ON. PERFORM IM240 SIMULATION THAT IS DESCRIBED ON COVER OF TOOL #6872.

DID PRESSURE DROP MORE THEN 8 IN. (H20) IN TWO MINUTES?

YES

CONTINUE TEST TC-160A ON THE NEXT PAGE.

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 3

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING, CONNECTORS AND HOSES.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 4 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
567

T TEST TC-160A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - EVAP LEAK MONITOR SMALL LEAK DETECTED

FIG. 1

568

TEST TC-160A CONTINUED - REPAIRING - EVAP LEAK MONITOR SMALL LEAK DETECTED

T R O U B L E C O D E T E S T S

TEST TC-160A CONTINUED FROM THE PREVIOUS PAGE.

TO CONTINUE TESTING, YOU WILL NEED MILLER TOOL ULTRASONIC LEAK DETECTOR (PARADISE 300).

NOTE: LDP SYSTEM TEST STILL GOING.

SET PRESSURE HOLD TO OPEN AND SET VENT TO CLOSED. TURN PUMP TIMER ON.

TO PREVENT NOISE FROM INTERFERING WITH TEST MOVE TOOL #6872A AWAY FROM VEHICLE.

USING THE ULTRASONIC LEAK DETECTOR, START LISTENING FOR LEAKS AT GAS CAP...

THEN PROCEED TO FUEL TANK ROLLOVER VALVE...

CANISTER, LEAK DETECTION PUMP AND EVAPORTIVE PURGE SOLENOID.

WERE ANY LEAKS HEARD WITH THE ULTRASONIC LEAK DETECTOR?

YES

REPAIR OR REPLACE LEAKING COMPONENT.*

NO

REPLACE THE LEAK DETECTION PUMP.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
569

T TEST TC-161A REPAIRING - EVAP LEAK MONITOR LARGE LEAK DETECTED R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2

FIG. 3
570

FIG. 4

TEST TC-161A REPAIRING - EVAP LEAK MONITOR LARGE LEAK DETECTED
Perform TEST DTC Before Proceeding

START TEST TC-161A.

NOTE: A LOOSE GAS CAP COULD CAUSE THIS TROUBLE CODE TO SET.

NOTE: THE FUEL TANK MUST HAVE AT LEAST THREE GALLONS OF FUEL TO PERFORM THIS THIS.

WARNING: READ FIGURE 1 BEFORE CONTINUING.

T R O U B L E C O D E

CONNECT A HAND VACUUM PUMP TO LDP VACUUM TEE (SVST PORT).

WITH HAND PUMP, APPLY 18 INCHES OF VACUUM TO LEAK DETECTION PUMP (LDP).

DOES THE PUMP HOLD VACUUM?

NO

ENSURE VACUUM LINES ARE OK BEFORE REPLACING LDP. PERFORM TC-161A TO VERIFY.

YES

T E S T S

REPLACE LDP. IGNITION KEY ON. WITH THE DRB, GO TO ACTUATIONS, ACTUATE LDP. DID VACUUM DROP WHEN SOLENOID WAS ACTUATED? NO PERFORM TEST TC-161A TO VERIFY.

YES

TO CONTINUE TESTING YOU WILL NEED MILLER TOOL KIT #6872A. FIG. 2

PERFORM EVAPORATIVE SYSTEM PRESSURE PUMP SELF TEST THAT IS SPECIFIED ON THE TESTER COVER.

CONNECT THE EVAP PRESSURE PUMP SUPPLY HOSE TO VEHICLE PRESSURE TEST PORT. SEE GEN INFO 4.2

USING AN AUXILARY CONTANT VACUUM SUPPLY, DRB IN LDP SYSTEM TEST PRESS 3 TO HOLD,...

DISCONNECT PURGE SOLENOID. SET PRESSURE HOLD TO OPEN, AND SET VENT TO CLOSED.

TURN PUMP TIMER ON. PERFORM IM240 SIMULATION THAT IS DESCRIBED ON COVER OF TOOL #6872.

DID PRESSURE DROP MORE THEN 8 IN. (H20) IN TWO MINUTES?

YES

CONTINUE TEST TC-161A ON THE NEXT PAGE.

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 3

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING, CONNECTORS AND HOSES.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

REFER TO FIGURE 4 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
571

T TEST TC-161A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - EVAP LEAK MONITOR LARGE LEAK DETECTED

FIG. 1

572

TEST TC-161A CONTINUED - REPAIRING - EVAP LEAK MONITOR LARGE LEAK DETECTED

TEST TC-161A CONTINUED FROM THE PREVIOUS PAGE.

TO CONTINUE TESTING YOU WILL NEED MILLER TOOL ULTRASONIC LEAK DETECTOR (PARADISE 300).

T R O U B L E C O D E

SET PRESSURE HOLD TO OPEN, AND SET VENT TO CLOSED. TURN PUMP TIMER ON.

TO PREVENT NOISE FROM INTERFERING WITH TEST MOVE TOOL #6872A (ESPP) AWAY FROM VEHICLE.

IF PUMP NOISE STILL INTERFERES WITH ULTRSASONIC LEAK TESTER TURN PRESSURE HOLD TO CLOSED...

T E S T S

AND TURN PUMP TIMER TO OFF.

NOTE: SYSTEM MUST HAVE PRESSURE TO DETECT A LEAK, IF THE EVAP SYSTEM CANNOT MAINTAIN...

PRESSURE, LEAVE PUMP TIMER ON AND PRESSURE HOLD TO OPEN.

USING MILLER TOOL #6904 ULTRASONIC LEAK DETECTOR, START LISTENING FOR LEAKS AT GAS CAP...

THEN PROCEED TO FUEL TANK ROLLOVER VALVE,...

CANISTER, LEAK DETECTION PUMP AND EVAPORTIVE PURGE SOLENOID.

WERE ANY LEAKS HEARD WITH THE ULTRASONIC LEAK DETECTOR?

YES

REPAIR OR REPLACE COMPONENT.*

NO

REPLACE LEAK DETECTION PUMP AND FILTER.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
573

T TEST TC-162A REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS R O Perform TEST DTC Before Proceeding U 1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 B TSB 26-06-97 June, 1997 L E C O D E T E S T S

FIG. 1

FIG. 2
574

TEST TC-162A REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS
Perform TEST DTC Before Proceeding
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

START TEST TC-162A.

WITH THE DRB ACTUATE #1 AIR INTAKE HEATER.

DOES THE RELAY CLICK ON AND OFF?

NO

PERFORM TEST TC-162C.

T R O U B L E C O D E

YES

WITH THE DRB, ACTUATE #2 AIR INTAKE HEATER.

DOES THE RELAY CLICK ON AND OFF?

NO

PERFORM TEST TC-162D.

YES

T E S T S

NOTE: BECAUSE HEATERS DRAW A LARGE AMOUNT OF CURRENT, ENSURE ACTUATION TIME IS BRIEF.

NOTE: IGNORE STOP ACTUATIONS IF STEPS IN TEST CAN BE PERFORMED QUICKLY.

WITH THE DRB, ACTUATE #1 AIR INTAKE HEATER.

USING A VOLTMETER, MEASURE THE #1 HEATER RELAY OUTPUT CKT AT THE INTAKE MANIFOLD. FIG. 1

STOP ACTUATION. NO DID THE VOLTAGE TOGGLE ABOVE 9.6 VOLTS? YES CONTINUE TEST TEST 162A ON THE NEXT PAGE.

WITH THE DRB, ACTUATE #2 AIR INTAKE HEATER.

USING A VOLTMETER, MEASURE THE #2 HEATER RELAY OUTPUT CKT AT THE INTAKE MANIFOLD. FIG. 1

STOP ACTUATION. NO DID THE VOLTAGE TOGGLE ABOVE 9.6 VOLTS? YES PERFORM TEST TC-162B.

REMOVE THE AIR INTAKE HEATER PER SERVICE MANUAL.**

INSPECT THE HEATER FOR AN OPEN CIRCUIT.

IS THE HEATER DEFECTIVE?

YES

REPLACE THE DEFECTIVE HEATER.*

NO

INSPECT THE INTAKE AIR TEMP SENSOR FOR HEAVY SOOT. REPLACE IF NECESSARY.

AT THIS TIME THE CONDITIONS REQUIRED TO SET THE CODE ARE NOT PRESENT. FIG. 2

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
575

T TEST TC-162A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS

1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

FIG. 1
576

TEST TC-162A CONTINUED - REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

START TEST TC-162B.

WITH THE DRB, ACTUATE #2 AIR INTAKE HEATER.

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE #2 HEATER RELAY OUTPUT CKT AT THE RELAY. FIG. 1

STOP ACTUATION. YES DID THE VOLTAGE TOGGLE ABOVE 9.6 VOLTS? NO

REPAIR THE OPEN #2 HEATER RELAY OUTPUT CIRCUIT.* NOTE: CHECK CIRCUIT FOR HIGH RESISTANCE

T E S T S

USING A VOLTMETER, MEASURE FUSED B(+) CIRCUIT AT #2 HEATER RELAY. FIG. 1

IS THE VOLTAGE BELOW 9.6 VOLTS?

YES

REPAIR THE OPEN FUSED B(+) CIRCUIT.*

NO

REPLACE THE AIR INTAKE HEATER #2 RELAY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
577

T TEST TC-162B REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS R O Perform TEST TC-162A Before Proceeding U 1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 B TSB 26-06-97 June, 1997 L E C O D E T E S T S

FIG. 1
578

TEST TC-162B REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS
Perform TEST TC-162A Before Proceeding
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

START TEST TC-162B.

WITH THE DRB, ACTUATE #2 AIR INTAKE HEATER.

T R O U B L E C O D E

USING A VOLTMETER, MEASURE THE #2 HEATER RELAY OUTPUT CKT AT THE RELAY. FIG. 1

STOP ACTUATION. YES DID THE VOLTAGE TOGGLE ABOVE 9.6 VOLTS? NO

REPAIR THE OPEN #2 HEATER RELAY OUTPUT CIRCUIT.* NOTE: CHECK CIRCUIT FOR HIGH RESISTANCE

T E S T S

USING A VOLTMETER, MEASURE FUSED B(+) CIRCUIT AT #2 HEATER RELAY. FIG. 1

IS THE VOLTAGE BELOW 9.6 VOLTS?

YES

REPAIR THE OPEN FUSED B(+) CIRCUIT.*

NO

REPLACE THE AIR INTAKE HEATER #2 RELAY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
579

T TEST TC-162C REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS R O Perform TEST TC-162A Before Proceeding 1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine U Publication No. 81-699-96103 B TSB 26-06-97 June, 1997 L E C O D E T E S T S

FIG. 1

FIG. 2
580

TEST TC-162C REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS
Perform TEST TC-162A Before Proceeding
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997
START TEST TC-162C. WITH THE DRB, STOP ALL ACTUATION TESTS.

T R O U B L E C O D E

DISCONNECT THE FUSED IGN SWITCH OUTPUT CKT CONNECTOR FROM #1 HEATER RLY.** FIG. 1

USING A VOLTMETER, MEASURE FUSED IGNITION SWITCH OUTPUT CKT AT RLY CONN. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.*

YES

T E S T S

RECONNECT THE FUSED IGNITION SWITCH OUTPUT CIRCUIT CONNECTOR. FIG. 1

DISCONNECT THE AIT HEATER RELAY #1 CONTROL CIRCUIT AT THE RELAY.** FIG. 1

USING A VOLTMETER, MEASURE THE TERMINAL AT THE RELAY CONNECTOR. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPLACE THE #1 HEATER RELAY.*

YES

TURN IGNITION OFF. DISCONNECT THE PCM BLACK CONNECTOR.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE #1 HEATER CONTROL CIRCUIT AT PCM TO GROUND. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE #1 HEATER RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE #1 HEATER CONTROL CIRCUIT...

FROM THE RELAY TO THE PCM. FIG.2

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN #1 HEATER RELAY CONTROL CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
581

T TEST TC-162D REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS R O Perform TEST TC-162A Before Proceeding 1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine U Publication No. 81-699-96103 B TSB 26-06-97 June, 1997 L E C O D E T E S T S

FIG. 1

FIG. 2
581A

TEST TC-162D REPAIRING - NO TEMP RISE SEEN FROM INTAKE HEATERS
Perform TEST TC-162A Before Proceeding
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

START TEST TC-162C.

WITH THE DRB, STOP ALL ACTUATION TESTS.

T R O U B L E C O D E

DISCONNECT THE FUSED IGN SWITCH OUTPUT CKT CONNECTOR FROM #1 HEATER RLY.** FIG. 1

USING A VOLTMETER, MEASURE FUSED IGNITION SWITCH OUTPUT CKT AT RLY CONN. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.*

YES

T E S T S

RECONNECT THE FUSED IGNITION SWITCH OUTPUT CIRCUIT CONNECTOR. FIG. 1

DISCONNECT THE AIT HEATER RELAY #1 CONTROL CIRCUIT AT THE RELAY.** FIG. 1

USING A VOLTMETER, MEASURE THE TERMINAL AT THE RELAY CONNECTOR. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPLACE THE #1 HEATER RELAY.*

YES

TURN IGNITION OFF. DISCONNECT THE PCM BLACK CONNECTOR.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE #1 HEATER CONTROL CIRCUIT AT PCM TO GROUND. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE #1 HEATER RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE #1 HEATER CONTROL CIRCUIT...

FROM THE RELAY TO THE PCM. FIG.2

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN #1 HEATER RELAY CONTROL CIRCUIT.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
581B

T TEST TC-164A REPAIRNG - TRANS TEMP SENSOR, NO RISE AFTER START R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1
582

TEST TC-164A REPAIRNG - TRANS TEMP SENSOR, NO RISE AFTER START
Perform TEST DTC Before Proceeding

START TEST TC-164A.

CHECK FOR A P/N SWITCH, TRANS TEMP SENSOR VOLTAGE TOO LOW OR TOO HIGH FAULT CODE.

WERE ANY OF THE FAULT CODES PRESENT?

YES

REPAIR FAULT CODE(S) FIRST.

T R O U B L E C O D E

NO

T0 TEST THE TRANS TEMP SENSOR, THE ENGINE AND TRANS TEMPERATURE MUST BE LESS THAN 85 DEG F.

IS THE ENGINE AND TRANS LESS THAN 85 DEGREES F?

NO

LET ENGINE AND TRANS COOL DOWN TO LESS THAN 85 DEG. F.

YES

T E S T S

READ ENGINE COOLANT TEMPERATURE SENSOR AND RECORD.

READ TRANSMISSION TEMPERATURE SENSOR TEMPERATURE AND RECORD.

IS THE TRANSMISSION TEMERATURE WITHIN 9 DEGREES OF ENGINE COOLANT TEMPERATURE?

NO

CONTINUE TEST TC-164A ON THE NEXT PAGE.

YES

START ENGINE AND LET IDLE IN DRIVE WITH PARKING BRAKE ON, WHILE MONITORING THE TRANS TEMP SENSOR.

LOOK FOR THE TEMPERATURE TO RAISE 15 DEGREES F OVER A TEN MINUTE PERIOD.

DID TRANS TEMP INCREASE AT A STEADY RATE AND INCREASE 15 DEGREES F OVER A TEN MINUTE PERIOD? YES

NO

CONTINUE TEST TC-164A ON THE NEXT PAGE.

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE THERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
583

T TEST TC-164A R O U B L E C O D E T E S T S

CONTINUED - REPAIRNG - TRANS TEMP SENSOR, NO RISE AFTER START

NOTES

584

TEST TC-164A CONTINUED - REPAIRNG - TRANS TEMP SENSOR, NO RISE AFTER START

T R O U B L E C O D E T E S T S

TEST TC-164A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE TRANSMISSION SOLENOID EIGHT WAY CONNECTOR.** SEE GENERAL INFO 4.2

WERE ALL OF THE CONNECTORS CLEAN AND UNDAMAGED?

NO

CLEAN OR REPAIR AS NECESSARY.*

YES

REPLACE TRANSMISSION TEMPERATURE/GOVERNOR PRESSURE SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
585

T TEST TC-165A REPAIRING - 3-4 SHIFT SOLENOID, NO RPM DROP 3-4 SHIFT R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

586

TEST TC-165A REPAIRING - 3-4 SHIFT SOLENOID, NO RPM DROP 3-4 SHIFT
Perform TEST DTC Before Proceeding

START TEST TC-165A.

WITH THE DRB READ TROUBLE CODES.

IS THE "TRANS 12 VOLT SUPPLY RELAY CONTROL CIRCUIT" TROUBLE CODE PRESENT? NO

YES

PERFORM TEST TC-173A.

T R O U B L E C O D E

IS THE "TORQUE CONVERTER CLUTCH SOLENOID" TROUBLE CODE PRESENT?

YES

PERFORM TEST TC-12A.

NO

T E S T S

IS THE "TRANS 3-4 SHIFT SOLENOID/TRANS RELAY CIRCUIT" TROUBLE CODE PRESENT? NO

YES

PERFORM TEST TC-50A.

IS THE "NO CAM SIGNAL AT PCM" TROUBLE CODE PRESENT?

YES

PERFORM TEST TC-01A.

NO

ARE ANY THROTTLE POSITION SENSOR CODES SET?

YES

PERFORM APPROPRIATE TEST FOR CODE.

NO

IS THE "P/N SWITCH STUCK IN PARK OR IN GEAR" TROUBLE CODE SET?

YES

PERFORM TEST TC-114A.

NO

CONTINUE TEST TC-165A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
587

T TEST TC-165A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 3-4 SHIFT SOLENOID, NO RPM DROP 3-4 SHIFT

FIG. 1

FIG. 2
588

TEST TC-165A CONTINUED - REPAIRING - 3-4 SHIFT SOLENOID, NO RPM DROP 3-4 SHIFT

TEST TC-165A CONTINUED FROM THE PREVIOUS PAGE.

CHECK TRANSMISSION FLUID LEVEL AND FOR ANY DEBRIS.

IS FLUID LEVEL OK AND CLEAR OF CONTAMINATION?

NO

REPAIR AS NECESSARY.*

T R O U B L E C O D E T E S T S

YES

CONNECT A ZERO TO 300 PSI PRESSURE GAUGE TO THE OVERDRIVE CLUTCH TEST PORT...

CONNECT ANOTHER ZERO TO 300 PSI GAUGE TO THE GOVERNOR TEST PORT. FIG. 1

START ENGINE AND ALLOW TRANS TEMP TO RISE TO NORMAL OPERATING TEMP.

WHILE OBSERVING THE PRESSURE GAUGES, SELECT 4TH GEAR FROM GOV AND 3-4 SYSTEM TEST.

THE GOVERNOR PRESSURE SHOULD RISE TO ABOVE 20 PSI. SHORTLY AFTER THIS,...

THE OD PRESSURE SHOULD RISE TO ABOVE 40 PSI.

DID THE PRESSURE ACT AS DESCRIBED?

YES

CONTINUE TEST TC-165A ON THE FOLLOWING PAGE.

NO

REPLACE 3-4 SHIFT SOLENOID. LEAVE GAUGES ATTACHED.

START ENGINE AND ALLOW THE TRANS TEMP TO RISE TO NORMAL OPERATING TEMP.

WHILE OBSERVING THE PRESSURE GAUGES, ACTUATE THE 3-4 SHIFT SOLENOID WITH THE DRB.

THE GOVERNOR PRESSURE SHOULD RISE TO ABOVE 20 PSI. SHORTLY AFTER THIS,...

THE OD PRESSURE SHOULD RISE TO ABOVE 40 PSI.

DID THE PRESSURE ACT AS DESCRIBED?

YES TEST COMPLETE.*

NO

OVERHAUL THE TRANSMISSION PER SERVICE MANUAL PROCEDURES.

PAY EXTRA ATTENTION TO SEALS AND CLUTCHES RELATED TO THE OD CLUTCH.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
589

T TEST TC-165A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 3-4 SHIFT SOLENOID, NO RPM DROP 3-4 SHIFT

NOTES

590

TEST TC-165A CONTINUED - REPAIRING - 3-4 SHIFT SOLENOID, NO RPM DROP 3-4 SHIFT

T R O U B L E C O D E T E S T S

TEST TC-165A CONTINUED FROM THE PREVIOUS PAGE.

REMOVE THE OIL PAN AND CHECK FOR EXCESSIVE DEBRIS AND/OR BURNT OIL.

IS THE OIL BURNT OR DOES THE PAN CONTAIN EXCESSIVE DEBRIS?

YES

REPAIR THE INTERNAL TRANSMISSION PROBLEM.*

NO

AT THIS TIME, THE CONDITIONS REQUIRED TO SET THIS CODE ARE NOT PRESENT.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
591

T TEST TC-166A REPAIRING - LOW OUTPUT SPEED SENSOR RPM, ABOVE 15 MPH R O Perform TEST DTC Before Proceeding U B L E C O D E T E S T S

FIG. 1
592

TEST TC-166A REPAIRING - LOW OUTPUT SPEED SENSOR RPM, ABOVE 15 MPH
Perform TEST DTC Before Proceeding

START TEST TC-166A.

WITH THE DRB, CHECK FOR A P/N SWITCH FAULT CODE.

WAS THERE A P/N SWITCH FAULT CODE?

YES

REPAIR THIS FAULT CODE FIRST.

T R O U B L E C O D E T E S T S

NO

RAISE THE DRIVE WHEELS OFF THE GROUND AND PROPERLY SUPPORT VEHICLE.

WARNING: BE SURE TO KEEP HANDS AND FEET CLEAR OF ROTATING WHEELS.

START ENGINE, WITH THE DRB, READ THE OUTPUT SPEED SENSOR.

PUT TRANSMISSION IN ANY FORWARD GEAR. RELEASE BRAKES TO LET WHEELS ROLL.

DOES THE DRB SHOW ABOVE 60 RPM?

NO

CONTINUE TEST TC-166A ON THE NEXT PAGE.

YES

WHILE STILL MONITORING THE OUTPUT SPEED SENSOR, WIGGLE THE WIRES FROM ...

THE OSS TO THE PCM.

DID THE READING DROP TOWARD ZERO WHILE WIGGLING THE WIRES?

YES

REPAIR INTERMITTENT SHORT OR OPEN CIRCUIT AREA WHERE FLUCTUATION OCCURRED.*

NO

ROAD TEST VEHICLE. WITH THE DRB, CLEAR TROUBLE CODES. WITH THE DRB, READ TROUBLE CODES. DID THE CODE RETURN? NO

THE CONDITIONS REQUIRED TO SET THIS CODE ARE NOT PRESENT AT THIS TIME. FIG. 1

YES

REPLACE OUTPUT SPEED SENSOR. ERASE TROUBLE CODES.

ROAD TEST VEHICLE. WITH THE DRB, READ TROUBLE CODES. DID THE CODE RETURN? NO TEST COMPLETE.*

YES

REPLACE THE PCM.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
593

T TEST TC-166A CONTINUED - REPAIRING - LOW OUTPUT SPEED SENSOR RPM, ABOVE 15 MPH R O U AB AND AN BODIES BR AND ZJ BODIES B L E C O D E T E S T S

FIG. 1
AB, AN AND ZJ BODIES BR BODY

FIG. 2

FIG. 3
594

FIG. 4

TEST TC-166A CONTINUED - REPAIRING - LOW OUTPUT SPEED SENSOR RPM, ABOVE 15 MPH

TEST TC-166A CONTINUED FROM PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

T R O U B L E C O D E

MEASURE THE RESISTANCE BETWEEN THE OSS SIGNAL CIRCUIT AND GROUND. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE OSS SIGNAL CIRCUIT SHORTED TO GROUND.*

NO

T E S T S

MEASURE THE RESISTANCE BETWEEN THE OSS GROUND CIRCUIT AND GROUND. FIG. 1 OR 2

IS THE RESISTANCE ABOVE 5.0 OHMS?

NO

REPAIR THE OSS GROUND CIRCUIT SHORTED TO GROUND.*

YES

MEASURE THE RESISTANCE BETWEEN THE OSS SIGNAL CIRCUIT AND...

THE OSS GROUND CIRCUIT AT THE PCM CONNECTOR. FIG. 1 OR 2

IS THE RESISTANCE BETWEEN 300.0 AND 1200.0 OHMS?

YES REPLACE THE PCM.*

NO

DISCONNECT THE OUTPUT SPEED SENSOR.** SEE GENERAL INFO 4.4

MEASURE THE RESISTANCE ACROSS BOTH TERMINALS OF THE OUTPUT SPEED SENSOR.

IS THE RESISTANCE BETWEEN 300.0 AND 1200.0 OHMS?

NO

REPLACE THE OUTPUT SPEED SENSOR.*

YES

MEASURE THE RESISTANCE OF THE OSS SIGNAL CIRCUIT FROM THE OSS CONNECTOR...

TO THE PCM CONNECTOR. FIG. 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN OSS SIGNAL CIRCUIT.*

NO

REPAIR THE OPEN OSS GROUND CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
595

T TEST TC-167A REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO LOW R O Perform TEST DTC Before Proceeding U AB BODY B L E C O D E T E S T S
FIG. 1
AN BODY BR BODY

FIG. 2
ZJ BODY

FIG. 3

FIG. 4
596

FIG. 5

TEST TC-167A REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO LOW
Perform TEST DTC Before Proceeding

START TEST TC-167A.

KEY OFF. DISCONNECT THE TRANS SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E

KEY ON, MEASURE THE VOLTAGE AT THE 5-VOLT SUPPLY CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE BETWEEN 4.5 AND 5.5 VOLTS?

NO

REPAIR THE OPEN 5-VOLT SUPPLY CIRCUIT.

YES

T E S T S

CONNECT SOLENOID CONNECTOR.

KEY ON, WITH THE DRB, MONITOR THE GOVERNOR PRESSURE VOLTAGE.

IS VOLTAGE ABOVE 4.65 VOLTS?

YES

PERFORM TEST TC-168A.

NO

IS THE VOLTAGE BELOW 0.12 VOLTS?

YES

CONTINUE TEST TC-167A ON THE NEXT PAGE.

NO

IS THE VOLTAGE BETWEEN 0.12 AND 0.80 VOLTS?

NO

PERFORM TEST 168B.

YES

WHILE MONITORING GOVERNOR PRESSURE VOLTAGE WITH DRB, WIGGLE THE WIRING AND CONNECTORS...

BETWEEN THE GOVERNOR PRESSURE SENSOR AND THE PCM.

DID THE VOLTAGE FLUCTUATE WHILE WIGGLING THE HARNESS?

YES

REPAIR WIRING WHERE WIGGLING CAUSED THE FLUCTUATION.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 5

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
597

T TEST TC-167A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO LOW
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
598

FIG. 4

TEST TC-167A CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO LOW

TEST TC-167A CONTINUED FROM PREVIOUS PAGE.

DISCONNECT THE TRANSMISSION SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

KEY OFF. DISCONNECT ALL OF THE PCM CONNECTORS.**

T R O U B L E C O D E T E S T S

MEASURE THE RESISTANCE BETWEEN THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT...

AND THE SENSOR GROUND CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO SENSOR GROUND CIRCUIT.*

NO

MEASURE THE RESISTANCE BETWEEN THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT...

AND GROUND. IS THE RESISTANCE BELOW 5.0 OHMS? FIG. 1, 2, 3 OR 4 NO YES

REPAIR THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND.*

REMOVE THE TRANS OIL PAN. DISCONNECT THE PRESSURE/TEMP SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

CONNECT THE TRANS SOLENOID CONNECTOR.

MEASURE THE RESISTANCE BETWEEN THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT...

AND THE SENSOR GROUND CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE TRANSMISSION HARNESS/SOLENOID ASSEMBLY.*

NO

MEASURE THE RESISTANCE BETWEEN THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT...

AND GROUND. IS THE RESISTANCE BELOW 5.0 OHMS? FIG. 1, 2, 3 OR 4 NO YES

REPLACE THE TRANSMISSION HARNESS/SOLENOID ASSEMBLY.*

RECONNECT ALL COMPONENTS EXCEPT THE PRESSURE/TEMP SENSOR.

KEY ON. WITH A DRB, MONITOR GOVERNOR PRESSURE SENSOR VOLTAGE.

IS THE VOLTAGE ABOVE 4.8 VOLTS?

NO REPLACE THE PCM.*

YES

REPLACE THE PRESSURE/TEMP SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
599

T TEST TC-168A REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH R O Perform TEST DTC Before Proceeding U AB BODY B L E C O D E T E S T S
FIG. 1
AN BODY BR BODY

FIG. 2
ZJ BODY

FIG. 3

FIG. 4
600

FIG. 5

TEST TC-168A REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH
Perform TEST DTC Before Proceeding

START TEST TC-168A.

KEY OFF. DISCONNECT THE TRANS SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E

KEY ON, MEASURE THE VOLTAGE AT THE 5-VOLT SUPPLY CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE BETWEEN 4.5 AND 5.5 VOLTS?

NO

REPAIR THE OPEN 5-VOLT SUPPLY CIRCUIT.*

YES

T E S T S

CONNECT SOLENOID CONNECTOR.

KEY ON, WITH THE DRB, MONITOR THE GOVERNOR PRESSURE VOLTAGE.

IS THE VOLTAGE ABOVE 4.65 VOLTS?

YES

CONTINUE TEST TC-168A ON THE NEXT PAGE.

NO

IS THE VOLTAGE BELOW 0.12 VOLTS?

YES

PERFORM TEST TC-167A.

NO

IS THE VOLTAGE BETWEEN 0.12 AND 0.80 VOLTS?

NO

PERFORM TEST 168B.

YES

WHILE MONITORING GOVERNOR PRESSURE VOLTAGE WITH DRB, WIGGLE THE WIRING AND CONNECTORS...

BETWEEN THE GOVERNOR PRESSURE SENSOR AND THE PCM.

DID THE VOLTAGE FLUCTUATE WHILE WIGGLING THE HARNESS?

YES

REPAIR WIRING WHERE WIGGLING CAUSED THE FLUCTUATION.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 5

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
601

T TEST TC-168A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
602

FIG. 4

TEST TC-168A CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH

T R O U B L E C O D E T E S T S

TEST TC-168A CONTINUED FROM PREVIOUS PAGE.

KEY OFF. DISCONNECT THE TRANSMISSION SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

DISCONNECT ALL OF THE PCM CONNECTORS.** SEE GENERAL INFO 4.1

MEASURE THE RESISTANCE OF THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT FROM...

THE PCM CONNECTOR TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT.*

NO

MEASURE THE RESISTANCE OF THE SENSOR GROUND CIRCUIT FROM...

THE PCM CONNECTOR TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

NO

CONTINUE TEST TC-168A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
603

T TEST TC-168A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
604

FIG. 4

TEST TC-168A CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH

T R O U B L E C O D E T E S T S

TEST TC-168A CONTINUED FROM PREVIOUS PAGE.

CONNECT A JUMPER WIRE FROM THE FUSED B(+) CIRCUIT TO THE TRANS CONTROL...

RELAY OUTPUT CIRCUIT IN THE RELAY CONNECTOR. FIG. 1, 2, 3 OR 4

KEY ON. MEASURE THE VOLTAGE AT THE GOVERNOR PRESSURE SIGNAL CIRCUIT...

AT THE PCM CONNECTOR. FIG. 1, 2, 3 OR 4 ON THE PRECEEDING PAGE

IS THE VOLTAGE ABOVE 1.0 VOLT?

YES

REPAIR THE GOVERNOR PRESSURE SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE.*

NO

REMOVE THE TRANS OIL PAN. DISCONNECT THE PRESSURE/TEMP SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

CONTINUE TEST TC-168A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
605

T TEST TC-168A R O U ALL BODIES B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH

FIG. 1
AB BODY AN BODY

FIG. 2
BR BODY ZJ BODY

FIG. 3

FIG. 4
606

FIG. 5

TEST TC-168A CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH

TEST TC-168A CONTINUED FROM THE PREVIOUS PAGE.

CONNECT THE SOLENOID CONNECTOR.

T R O U B L E C O D E

KEY ON. MEASURE THE VOLTAGE AT THE GOVERNOR PRESSURE SIGNAL CIRCUIT. FIG. 1

IS THE VOLTAGE ABOVE 1.0 VOLT?

YES

REPLACE THE TRANSMISSION HARNESS/SOLENOID ASSEMBLY.*

NO

T E S T S

KEY OFF. MEASURE THE RESISTANCE OF THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT FROM THE...

PCM CONNECTOR TO THE GOVERNOR PRESSURE SENSOR CONNECTOR. FIG. 2, 3, 4 OR 5

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPLACE THE TRANSMISSION HARNESS/SOLENOID ASSEMBLY.*

NO

MEASURE THE RESISTANCE OF THE SENSOR GROUND CIRCUIT FROM THE PCM...

CONNECTOR TO THE GOVERNOR PRESSURE SENSOR CONNECTOR. FIG. 2, 3, 4 OR 5

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPLACE THE TRANSMISSION HARNESS/SOLENOID ASSEMBLY.*

NO

RECONNECT ALL CONNECTORS EXCEPT THE GOVERNOR PRESSURE SENSOR CONNECTOR.

CAREFULLY INSERT A JUMPER WIRE BETWEEN THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT...

AND THE SENSOR GROUND CIRCUIT IN THE SENSOR CONNECTOR. FIG. 1

KEY ON. MONITOR THE GOVERNOR PRESSURE SENSOR VOLTAGE WITH THE DRB.

IS THE VOLTAGE ABOVE 0.1 VOLTS?

NO

REPLACE THE PRESSURE/TEMP SENSOR.*

YES

REPLACE THE PCM.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
607

T TEST TC-168B REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH R O Perform TEST TC-168A Before Proceeding U AB BODY AN BODY B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
608

FIG. 4

TEST TC-168B REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH
Perform TEST TC-168A Before Proceeding

START TEST TC-168B.

DISCONNECT THE WHITE PCM CONNECTOR.** SEE GENERAL INFO 4.1

T R O U B L E C O D E

START ENGINE.

WITH THE DRB, MONITOR GOVERNOR PRESSURE SENSOR VOLTAGE.

IS VOLTAGE ABOVE 4.65 VOLTS?

NO REPLACE THE PCM.*

YES

T E S T S

KEY OFF. DISCONNECT THE REMAINING PCM CONNECTORS.**

DISCONNECT THE TRANS SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

MEASURE THE RESISTANCE OF THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT FROM...

THE PCM CONNECTOR TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT.*

NO

MEASURE THE RESISTANCE OF THE SENSOR GROUND CIRCUIT FROM...

THE PCM CONNECTOR TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

NO

KEY ON. MEASURE THE VOLTAGE AT THE GOVERNOR PRESSURE SIGNAL CIRCUIT...

AT THE PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 1.0 VOLT?

YES

REPAIR THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE.*

NO

CONTINUE TEST TC-168B ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
609

T TEST TC-168B R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
610

FIG. 4

TEST TC-168B CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH

T R O U B L E C O D E T E S T S

TEST TC-168B CONTINUED FROM PREVIOUS PAGE.

REMOVE THE TRANS OIL PAN. DISCONNECT THE PRESSURE/TEMP SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

RECONNECT THE SOLENOID CONNECTOR.

KEY ON. MEASURE THE VOLTAGE AT THE GOVERNOR PRESSURE SIGNAL CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 1.0 VOLT?

YES

REPLACE THE TRANSMISSION HARNESS/SOLENOID ASSEMBLY.*

NO

CONTINUE TEST TC-168B ON THE FOLLOWING PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
611

T TEST TC-168B R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
612

FIG. 4

TEST TC-168B CONTINUED - REPAIRING - GOVERNOR PRESSURE SENSOR VOLTS TOO HIGH

T R O U B L E C O D E T E S T S

TEST TC-168B CONTINUED FROM PREVIOUS PAGE.

REMOVE THE TRANS OIL PAN. DISCONNECT THE PRESSURE/TEMP SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

MEASURE THE RESISTANCE OF THE GOVERNOR PRESSURE SENSOR SIGNAL CIRCUIT FROM THE...

PCM CONNECTOR TO THE GOVERNOR PRESSURE SENSOR CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPLACE THE TRANSMISSION HARNESS/SOLENOID ASSEMBLY.*

NO

MEASURE THE RESISTANCE OF THE SENSOR GROUND CIRCUIT FROM THE PCM...

CONNECTOR TO THE GOVERNOR PRESSURE SENSOR CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPLACE THE TRANSMISSION HARNESS/SOLENOID ASSEMBLY.*

NO

REPLACE THE PRESSURE/TEMP SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
613

T TEST TC-169A REPAIRING - GOVERNOR PRESSURE SENSOR OFFSET VOLTS TOO LOW OR HIGH R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1
614

TEST TC-169A REPAIRING - GOVERNOR PRESSURE SENSOR OFFSET VOLTS TOO LOW OR HIGH
Perform DTC TEST Before Proceeding

START TEST TC-169A

START ENGINE, ALLOW TO WARM UP AND CHECK FLUID LEVEL AND CONDITION OF FLUID.

WAS FLUID CONDITION AND LEVEL OK?

NO

REPAIR FLUID LEVEL AND/OR CONDITION OF BAD FLUID AND RETEST.*

T R O U B L E C O D E T E S T S

YES

CHECK PARK/NEUTRAL SWITCH FOR PROPER OPERATION.

WAS THE PARK/NEUTRAL SWITCH OPERATION OK?

NO

REPAIR PARK/NEUTRAL SWITCH AS NECESSARY.*

YES

PLACE VEHICLE IN NEUTRAL, WITH THE DRB, READ THE GOVERNOR PRESSURE SENSOR VOLTAGE.

WAS THE VOLTAGE BETWEEN 0.3 AND 0.76 VOLTS?

NO

CONTINUE TEST TC-169A ON NEXT PAGE.

YES

WHILE MONITORING GOVERNOR PRESSURE VOLTAGE WITH DRB, WIGGLE THE WIRING AND CONNECTORS...

BETWEEN THE GOVERNOR PRESSURE SENSOR AND THE PCM.

DID THE VOLTAGE FLUCTUATE WHILE WIGGLING THE HARNESS?

YES

REPAIR WIRING WHERE WIGGLING CAUSED THE FLUCTUATION.*

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
615

T TEST TC-169A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING GOVERNOR PRESSURE SENSOR OFFSET VOLTS TOO LOW OR HIGH
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
616

FIG. 4

- REPAIRING GOVERNOR PRESSURE SENSOR OFFSET VOLTS TOO TEST TC-169A CONTINUED LOW OR HIGH

TEST TC-169A CONTINUED FROM PREVIOUS PAGE

KEY ON, ENGINE OFF. DISCONNECT THE TRANS SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E

MEASURE VOLTAGE AT THE 5-VOLT SUPPLY CIRCUIT IN TRANS SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

WAS THE VOLTAGE ABOVE 4.5 VOLTS?

NO

REPAIR THE OPEN 5-VOLT SUPPLY CIRCUIT.*

YES

T E S T S

TURN KEY OFF. DISCONNECT THE PCM CONNECTOR.** SEE GENERAL INFO 4.1

MEASURE THE RESISTANCE OF THE SENSOR GROUND CIRCUIT FROM THE PCM CONNECTOR...

TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4 ON THE FOLLOWING PAGE.

WAS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

YES

RECONNECT ALL CONNECTORS. START ENGINE.

WHILE STILL MONITORING GOVERNOR PRESSURE SENSOR VOLTAGE,...

WIGGLE THE WIRES BETWEEN THE PCM AND THE SOLENOID CONNECTOR.

DID THE GOVERNOR PRESSURE SENSOR VOLTAGE FLUCTUATE WHILE WIGGLING THE WIRES? NO

YES

REPAIR WIRING WHERE WIGGLING CAUSED THE FLUCTUATION.*

CONTINUE TEST 169A ON FOLLOWING PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
617

T TEST TC-169A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING GOVERNOR PRESSURE SENSOR OFFSET VOLTS TOO LOW OR HIGH

FIG. 1

FIG. 2
618

- REPAIRING GOVERNOR PRESSURE SENSOR OFFSET VOLTS TOO TEST TC-169A CONTINUED LOW OR HIGH

T R O U B L E C O D E T E S T S

TEST 169A CONTINUED FROM THE PREVIOUS PAGE.

WITH THE DRB, CLEAR TROUBLE CODES.

START ENGINE. LET ENGINE IDLE IN PARK OR NEUTRAL FOR 3 MINUTES.

DID CODE COME BACK AFTER 3 MINUTES OF ENGINE IDLING?

NO

THE CONDITIONS REQUIRED TO SET THIS CODE ARE NOT PRESENT AT THIS TIME. FIG. 1 AND 2

YES

REPLACE THE GOVERNOR PRESSURE SENSOR.*

CHECK PAN AND/OR FILTER FOR EXCESSIVE DEBRIS WHILE CHANGING SENSOR.

DOES THE PAN AND/OR FILTER CONTAIN EXCESSIVE DEBRIS?

YES

REPAIR CAUSE OF EXCESSIVE DEBRIS.*

NO

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
619

T TEST TC-171A REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1
620

TEST TC-171A REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS
Perform DTC TEST Before Proceeding

START TEST TC-171A

IS THE TRANS 12-VOLT SUPPLY RELAY CONTROL CIRCUIT CODE SET?

T R O U B L E C O D E T E S T S

YES

PERFORM TEST TC-173.

NO

WITH THE DRB, PERFORM A GOV AND 3-4 SHIFT VALVE SYSTEM TEST.

SELECT 1ST GEAR. READ GOVERNOR PRESSURE VOLTAGE. IS THE GOVERNOR PRESSURE VOLTAGE BELOW 1.0 VOLTS? NO CONTINUE TEST TC-171A ON THE NEXT PAGE.

YES

AT THIS TIME, THE CONDITION REQUIRED TO SET THIS CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH THE DRB, CLEAR CODES. START THE ENGINE.

WHILE READING DTC’S WITH THE DRB, WIGGLE THE WIRING HARNESS FROM THE SOLENOID TO THE PCM.

DOES THE GOVERNOR PRESSURE SOLENOID CONTROL CIRCUIT FAULT CODE APPEAR?

YES

REPAIR WIRING AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
621

T TEST TC-171A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS

AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
622

FIG. 4

TEST TC-171A CONTINUED - REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS T

R O U B L E C O D E

TEST TC-171A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE TRANS SOLENOID PACK CONNECTOR.** SEE GENERAL INFO 4.2

T E S T S

KEY ON. WITH THE DRB, ACTUATE THE TRANS CONTROL RELAY.

MEASURE THE VOLTAGE AT THE TRANS RELAY OUTPUT CIRCUIT. FIG. 1, 2, 3 OR 4

DOES THE VOLTAGE FLUCTUATE FROM 0 VOLTS TO OVER 10.0 VOLTS?

NO

PERFORM TEST TC-171B.

YES

CONTINUE TEST TC-171A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
623

T TEST TC-171A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS

AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
624

FIG. 4

TEST TC-171A CONTINUED - REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS T

TEST TC-171A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE WHITE CONNECTOR.** SEE GENERAL INFO 4.1

R O U B L E C O D E T E S T S

KEY ON. MEASURE THE VOLTAGE AT THE GOV. PRESSURE SOLENOID CONTROL CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

PERFORM TEST TC-171D.

NO

RECONNECT THE SOLENOID PACK CONNECTOR.

KEY OFF. MEASURE THE RESISTANCE BETWEEN THE GOVERNOR PRESSURE SOLENOID CONTROL CIRCUIT...

AT THE PCM CONNECTOR AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

NO

REPAIR THE GOVERNOR PRESSURE SOLENOID CONTROL CIRCUIT SHORTED TO GROUND.*

YES

CONTINUE TEST TC-171A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
625

T TEST TC-171A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS

AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
626

FIG. 4

TEST TC-171A CONTINUED - REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS T

R O U B L E C O D E T E S T S

TEST TC-171A CONTINUED FROM THE PREVIOUS PAGE.

REMOVE THE TRANS CONTROL RELAY.** SEE GENERAL INFO 4.6

MEASURE THE RESISTANCE BETWEEN THE TRANS CONTROL RELAY OUTPUT CIRCUIT AT THE RELAY...

AND THE GOVERNOR PRESSURE SOLENOID CONTROL CIRCUIT AT THE PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BETWEEN 2.5 AND 5.0 OHMS?

YES REPLACE THE PCM.*

NO

IS THE RESISTANCE ABOVE 5.0 OHMS?

NO

PERFORM TEST TC-171C.

YES

CONTINUE TEST TC-171A ON THE FOLLOWING PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
627

T TEST TC-171A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS

AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
628

FIG. 4

TEST TC-171A CONTINUED - REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS T

R O U B L E C O D E T E S T S

TEST TC-171A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE TRANS SOLENOID PACK CONNECTOR.** SEE GENERAL INFO 4.2

MEASURE THE RESISTANCE OF THE GOVERNOR PRESSURE SOLENOID CONTROL CIRCUIT...

FROM THE PCM CONNECTOR TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN GOVERNOR PRESSURE SOLENOID CONTROL CIRCUIT.*

NO

DRAIN AND REMOVE OIL PAN. DISCONNECT THE GOVERNOR PRESSURE SOLENOID.** SEE GENERAL INFO 4.2

MEASURE THE RESISTANCE ACROSS THE GOVERNOR PRESSURE SOLENOID.

IS THE RESISTANCE ABOVE 5.0 OHMS?

NO

REPLACE THE SOLENOID AND HARNESS ASSEMBLY.*

YES

REPLACE THE GOVERNOR PRESSURE SOLENOID.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
629

T TEST TC-171B REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS R O Perform TEST TC-171A Before Proceeding U AB BODY AN BODY B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
630

FIG. 4

TEST TC-171B REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS
Perform TEST TC-171A Before Proceeding

START TEST TC-171B.

REMOVE THE TRANS CONTROL RELAY.** SEE GENERAL INFO 4.6

T R O U B L E C O D E T E S T S

KEY OFF. MEASURE THE RESISTANCE BETWEEN THE TRANS RELAY OUTPUT CIRCUIT...

AND GROUND AT THE RELAY CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE TRANS RELAY OUTPUT CIRCUIT SHORTED TO GROUND.*

NO

MEASURE THE RESISTANCE OF THE TRANS RELAY OUTPUT CIRCUIT...

FROM THE RELAY CONNECTOR TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN TRANS RELAY OUTPUT CIRCUIT.*

NO

KEY ON, MEASURE THE VOLTAGE AT THE FUSED B(+) CIRCUIT IN THE RELAY CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS ?

NO

REPAIR THE OPEN FUSED B(+) FEED TO THE TRANS CONTROL RELAY.

YES

REPLACE THE TRANS CONTROL RELAY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
631

T TEST TC-171C REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS R O Perform TEST TC-171A Before Proceeding U AB BODY AN BODY B L E C O D E T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
632

FIG. 4

TEST TC-171C REPAIRING - GOVERNOR PRESSURE SOLENOID/TRANS RELAY CKTS
Perform TEST TC-171A Before Proceeding

START TEST TC-171C.

DISCONNECT THE TRANS SOLENOID CONNECTOR.** SEE GENERAL INFO 4.2

T R O U B L E C O D E

MEASURE AND RECORD THE RESISTANCES BETWEEN THE GOVERNOR PRESSURE SOLENOID CONTROL CIRCUIT...

AND ALL OTHER CIRCUITS IN THE SOLENOID CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 2.5 OHMS BETWEEN ANY TWO CIRCUITS?

YES

REPAIR GOVERNOR PRESSURE SOLENOID CONTROL CKT SHORTED TO CIRCUIT(S) THAT WERE BELOW 2.5 OHMS.

NO

T E S T S

REMOVE THE TRANS OIL PAN. DISCONNECT THE GOVERNOR PRESSURE SOLENOID.**

MEASURE THE RESISTANCE ACROSS BOTH TERMINALS OF THE GOVERNOR PRESSURE SOLENOID.

IS THE RESISTANCE BELOW 2.5 OHMS?

YES

REPLACE THE GOVERNOR PRESSURE SOLENOID.*

NO

REPLACE THE TRANS HARNESS/SOLENOID ASSEMBLY.*

RECONNECT ALL DISCONNECTED CONNECTORS.

WITH THE DRB, PERFORM THE GOV AND 3-4 SHIFT VALVE SYSTEM TEST.

SELECT 1ST GEAR. READ THE GOVERNOR PRESSURE VOLTAGE. IS THE GOVERNOR PRESSURE VOLTAGE BELOW 1.0 VOLT? NO REPLACE THE PCM.*

YES

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
633

T TEST TC-171D REPAIRING - TRANS 3-4 SOLENOID/TRANS RELAY CKT R O Perform TEST TC-171A Before Proceeding U NOTES B L E C O D E T E S T S

634

TEST TC-171D REPAIRING - TRANS 3-4 SOLENOID/TRANS RELAY CKT
Perform TEST TC-171A Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-171D.

REPAIR GOVERNOR PRESSURE SOLENOID CONTROL CIRCUIT SHORTED TO VOLTAGE.*

RECONNECT ALL DISCONNECTED CONNECTORS.

WITH THE DRB, PERFORM THE GOV AND 3-4 SHIFT VALVE SYSTEM TEST.

SELECT 1ST GEAR. READ THE GOVERNOR PRESSURE VOLTAGE. IS THE GOVERNOR PRESSURE VOLTAGE BELOW 1.0 VOLT? NO REPLACE THE PCM.*

YES

TEST COMPLETE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
635

T TEST TC-173A REPAIRING - TRANS 12 VOLT SUPPLY RELAY CNTRL CIRCUIT R O Perform DTC TEST Before Proceeding U AB BODY AN BODY B L E C O D E T E S T S

BR BODY

ZJ BODY

FIG. 1
636

FIG. 2

TEST TC-173A REPAIRING - TRANS 12 VOLT SUPPLY RELAY CNTRL CIRCUIT
Perform DTC TEST Before Proceeding

START TEST TC-173A.

WITH THE DRB, ACTUATE THE TRANSMISSION CONTROL RELAY.

IS THE TRANSMISSION CONTROL RELAY CLICKING?

T R O U B L E
CONTINUE TEST TC-173A ON THE NEXT PAGE.

NO

YES

C O D E T E S T S

THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WIGGLE THE WIRING HARNESS FROM THE RELAY TO THE POWERTRAIN CONTROL MODULE.

NOTE: THE DRB MUST STILL BE ACTUATING THE TRANS CONTROL RELAY.

DID THE WIGGLING INTERRUPT THE CLICKING?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED THE CLICKING TO BE INTERRUPTED.*

NO

REFER TO FIG. 2 FOR INACTIVE TROUBLE CODE CONDITION INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
637

T TEST TC-173A R O U AB BODY B L E C O D E T E S T S

CONTINUED - REPAIRING - TRANS 12 VOLT SUPPLY RELAY CNTRL CIRCUIT
AN BODY

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3

FIG. 4

FIG. 5
638

FIG. 6

TEST TC-173A CONTINUED - REPAIRING - TRANS 12 VOLT SUPPLY RELAY CNTRL CIRCUIT

TEST TC-173A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE TRANSMISSION CONTROL RELAY.** SEE GENERAL INFO 4.6

T R O U B L E C O D E

MEASURE THE VOLTAGE AT THE FUSED IGN SW OUTPUT CIRCUIT IN THE RELAY CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.*

YES

T E S T S

MEASURE THE RESISTANCE BETWEEN TERMINALS 85 AND 86...

OF THE TRANS CONTROL RELAY. FIG. 5 OR 6

IS THE RESISTANCE BELOW 100.0 OHMS?

NO

REPLACE THE TRANSMISSION CONTROL RELAY.*

YES

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE WHITE CONNECTOR.** SEE GENERAL INFO 4.1

MEASURE THE RESISTANCE BETWEEN THE TRANS RELAY CONTROL CIRCUIT...

AND GROUND. IS THE RESISTANCE BELOW 5.0 OHMS? FIG. 1, 2, 3 OR 4 NO YES

REPAIR THE TRANSMISSION RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND.*

MEASURE THE RESISTANCE OF THE TRANS RELAY CONTROL CIRCUIT...

FROM THE RELAY TO THE PCM. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR OPEN TRANSMISSION RELAY CONTROL CIRCUIT.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
639

T TEST TC-181A REPAIRING - 2/1 O2 SENSOR SHORTED TO GROUND R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

640

TEST TC-181A REPAIRING - 2/1 O2 SENSOR SHORTED TO GROUND
Perform DTC TEST Before Proceeding

START TEST TC-181A.

REFER TO THE FIGURE FOR POSSIBLE TROUBLE CODE CAUSES. FIG. 1

T R O U B L E C O D E T E S T S

IF ENGINE IS WARM, TURN THE ENGINE OFF FOR 15 MINUTES TO ALLOW O2 SENSOR TO COOL DOWN.

TURN INGITION ON. (ENGINE OFF)

WITH THE DRB, MONITOR THE 2/1 O2 SENSOR VOLTAGE.

IS THE 2/1 O2 SENSOR VOLTAGE BELOW 0.16V?

YES

CONTINUE TEST TC-181A ON THE NEXT PAGE.

NO

NOTE: A SHORTED LOW CONDITION DUE TO WATER IN THE SENSOR CONNECTOR, MAY BE TEMPORARY.

WIGGLE THE 2/1 O2 SENSOR HARNESS AND MONITOR THE VOLTAGE.

DID THE 2/1 O2 SENSOR VOLTAGE CHANGE WHILE WIGGLING THE HARNESS? YES

NO

THE CONDITION REQUIRED TO SET THIS TROUBLE CODE IS NOT PRESENT AT THIS TIME.*

REPAIR THE HARNESS OR WIRING THAT HAS THE INTERMITTENT SHORT TO GROUND.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
641

T TEST TC-181A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 2/1 O2 SENSOR SHORTED TO GROUND

FIG. 1

642

TEST TC-181A CONTINUED - REPAIRING - 2/1 O2 SENSOR SHORTED TO GROUND

CONTINUE TEST TC-181A FROM THE PREVIOUS PAGE.

DISCONNECT THE 2/1 O2 SENSOR.** SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

T R O U B L E C O D E

NO

WITH THE DRB, READ THE 2/1 O2 SENSOR VOLTAGE.

IS THE VOLTAGE BELOW 0.16 VOLTS?

NO

REPLACE THE 2/1 O2 SENSOR.*

YES

T E S T S

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTORS.** SEE GENERAL INFO 4.1

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

USING AN OHMMETER, IN THE FOLLOWING STEP.

MEASURE THE 2/1 02 SENSOR SIGNAL CIRCUIT FROM THE PCM CONNECTOR TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE 2/1 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

NO

WIGGLE THE O2 SENSOR HARNESS WHILE CHECKING RESISTANCE OF O2 SENSOR SIGNAL CIRCUIT.

DID THE RESISTANCE CHANGE WHILE WIGGLING THE HARNESS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE 2/1 O2 SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
643

T TEST TC-183A REPAIRING - LEAK DETECTION PUMP SOLENOID CIRCUIT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG.1

FIG. 2
644

TEST TC-183A REPAIRING - LEAK DETECTION PUMP SOLENOID CIRCUIT
Perform DTC TEST Before Proceeding

START TEST TC-183A.

START ENGINE AND LET IDLE.

WITH THE DRB, READ THE LDP PRESSURE SWITCH STATE AND NOTE POSITION.

T R O U B L E C O D E

WITH THE DRB, ACTUATE THE LDP PUMP SOLENOID.

WITH THE DRB, READ THE LDP PRESSURE SWITCH STATE.

DID THE DRB SHOW THE LEAK DETECTION PRESSURE SWITCH CHANGE FROM DOWN TO UP? YES

NO

CONTINUE TEST TC-183A ON THE NEXT PAGE.

T E S T S

WITH THE DRB, STOP ACTUATION OF THE LDP PUMP SOLENOID.

WITH THE DRB, READ THE LDP PRESSURE SWITCH STATE.

DID THE DRB SHOW THE LEAK DETECTION PRESSURE SWITCH CHANGE FROM UP TO DOWN? YES

NO

CONTINUE TEST TC-183A ON THE NEXT PAGE.

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH THE DRB, ACTUATE THE LDP SOLENOID.

WHILE MONITORING THE LDP SWITCH STATE, WIGGLE WIRING HARNESS FROM THE LDP SOLENOID TO PCM.

DID THE LDP SWITCH STATE EVER CHANGE FROM UP TO DOWN WHEN WIGGLED?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED PROBLEM TO APPEAR.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
645

T TEST TC-183A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - LEAK DETECTION PUMP SOLENOID CIRCUIT

FIG. 1

FIG. 2
646

TEST TC-183A CONTINUED - REPAIRING - LEAK DETECTION PUMP SOLENOID CIRCUIT

TEST TC-183A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE LEAK DETECTION PUMP SOLENOID.** SEE GENERAL INFO 4.0

T R O U B L E C O D E

KEY ON, USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE FUSED IGNITION SWITCH OUTPUT CKT AT SOLENOID CONN. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CKT.*

YES

T E S T S

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

USING AN OHMMETER, MEASURE THE LDP SOLENOID CONTROL CIRCUIT...

FROM THE PCM CONNECTOR TO THE LDP CONNECTOR. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN LEAK DETECTION PUMP SOLENOID CONTROL CIRCUIT.*

YES

USING AN OHMMETER, MEASURE THE LEAK DETECTION PUMP SOLENOID CONTROL CIRCUIT...

AT THE POWERTRAIN CONTROL MODULE. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE LEAK DETECTION PUMP SOLENOID CIRCUIT FOR A SHORT TO GROUND.*

NO

RECONNECT THE LEAK DETECTION PUMP CONNECTOR. KEY ON, WITH A VOLTMETER, MEASURE...

THE LEAK DETECTION PUMP SOLENOID CONTROL CIRCUIT AT THE PCM CONNECTOR. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPLACE THE LEAK DETECTION PUMP.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
647

T TEST TC-184A REPAIRING - LEAK DETECTION PUMP SW OR MECHANICAL FAULT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

FIG. 2
648

TEST TC-184A REPAIRING - LEAK DETECTION PUMP SW OR MECHANICAL FAULT
Perform DTC TEST Before Proceeding

START TEST TC-184A.

START ENGINE AND LET IDLE.

WITH THE DRB, READ THE LDP PRESSURE SWITCH STATE.

T R O U B L E C O D E

WITH THE DRB, ACTUATE THE LDP PUMP SOLENOID.

WITH THE DRB, READ THE LDP PRESSURE SWITCH STATE.

DID THE DRB SHOW THE LEAK DETECTION PRESSURE SWITCH CHANGE FROM UP TO DOWN? YES

NO

CONTINUE TEST TC-184A ON THE NEXT PAGE.

T E S T S

WITH THE DRB, STOP ACTUATION OF THE LDP PUMP SOLENOID.

WITH THE DRB, READ THE LDP PRESSURE SWITCH STATE.

DID THE DRB SHOW THE LEAK DETECTION PRESSURE SWITCH CHANGE FROM DOWN TO UP? YES

NO

CONTINUE TEST TC-184A ON THE NEXT PAGE.

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 1

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

WITH THE DRB, ACTUATE THE LDP SOLENOID.

WHILE MONITORING THE LDP SWITCH STATE, WIGGLE WIRING HARNESS FROM THE LDP SOLENOID TO PCM.

DID THE LDP SWITCH STATE EVER CHANGE FROM UP TO DOWN WHEN WIGGLED?

YES

REPAIR AS NECESSARY WHERE WIGGLING CAUSED PROBLEM TO APPEAR.*

NO

REFER TO FIGURE 2 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
649

T TEST TC-184A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - LEAK DETECTION PUMP SW OR MECHANICAL FAULT

FIG. 1

FIG. 2
650

TEST TC-184A CONTINUED - REPAIRING - LEAK DETECTION PUMP SW OR MECHANICAL FAULT

TEST TC-184A CONTINUED FROM THE PREVIOUS PAGE.

CONNECT A VACUUM GAUGE INTO THE VACUUM TEE TO THE LDP. SEE GENERAL INFO 4.0

T R O U B L E C O D E

START THE ENGINE AND READ THE VACUUM GAUGE.

DOES THE VACUUM GAUGE READ WITHIN 1 INCH OF ENGINE VACUUM.

NO

REPAIR THE LEAK OR OBSTRUCTION IN THE VACUUM HOSE.*

YES

T E S T S

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

KEY ON. USING A VOLTMETER, MEASURE THE LDP PRESSURE SWITCH CIRCUIT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

REPLACE THE LEAK DETECTION PUMP.*

NO

DISCONNECT THE LEAK DETECTION PUMP CONNECTOR.** SEE GENERAL INFO 4.0

MEASURE THE FUSED IGNITION SWITCH OUTPUT CIRCUIT. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CKT.*

YES

USING AN OHMMETER, MEASURE THE LDP PRESSURE SWITCH CIRCUIT...

FROM THE PCM CONNECTOR TO THE LDP CONNECTOR. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR OPEN LEAK DETECTION PUMP SWITCH SENSE CIRCUIT.*

YES

REPLACE THE LEAK DETECTION PUMP.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
651

T TEST TC-186A REPAIRING - MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

AB, AN, BR, AND XJ BODIES

ZJ BODY

652

TEST TC-186A REPAIRING - MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT
Perform DTC TEST Before Proceeding

START TEST TC-186A.

DISCONNECT THE CRANKSHAFT POSITION CONNECTOR.** INSPECT ALL TERMINALS. SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

T R O U B L E C O D E

NO

INSPECT THE CRANKSHAFT POSITION SENSOR FOR PROPER INSTALLATION. SEE GENERAL INFO 4.4

IS THE CRANKSHAFT POSITION SENSOR PROPERLY INSTALLED?

NO

PROPERLY INSTALL CRANKSHAFT POSITION SENSOR.*

YES

T E S T S

NO

IS THE VEHICLE EQUIPPED WITH AN 8.0L ENGINE?

YES

INSPECT THE CRANKSHAFT NOTCHES FOR DAMAGE OR MISALIGNMENT.

IS THE CRANKSHAFT OKAY?

NO

REPAIR AS NECESSARY.*

YES

REPLACE THE CRANKSHAFT POSITION SENSOR.*

INSPECT THE FLYWHEEL FOR DAMAGE OR MISALIGNMENT.

IS THE FLYWHEEL DAMAGED?

YES

REPAIR AS NECESSARY.*

NO

REPLACE THE CRANKSHAFT POSITION SENSOR.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
653

T TEST TC-187A REPAIRING - EVAP LEAK MONITOR PINCHED HOSE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1
654

FIG. 2

TEST TC-187A REPAIRING - EVAP LEAK MONITOR PINCHED HOSE
Perform DTC TEST Before Proceeding

START TEST TC-187A.

TO PERFORM THIS TEST YOU WILL NEED MILLER TOOL KIT #6872A. FIG. 1

T R O U B L E C O D E T E S T S

CAUTION: REFER TO FIGURE 2 FOR SAFETY INFORMATION.

PERFORM EVAPORATIVE SYSTEM PRESSURE PUMP SELF TEST THAT IS SPECIFIED ON THE TESTER COVER.

CONNECT THE EVAP PRESSURE PUMP SUPPLY HOSE TO VEHICLE PRESSURE TEST PORT. SEE GENERAL INFO 4.2

USING AN AUXIILIARY CONSTANT VACUUM SUPPLY, WITH THE DRB, GO TO LDP SYSTEM TEST,...

FOLLOW THE INSTRUCTIONS ON THE SCREEN.

USING PRESSURE TOOL #6872A SET PRESSURE HOLD TO OPEN, AND SET VENT CLOSED. TURN PUMP TIMER ON.

DISCONNECT THE PURGE SOLENOID CONNECTOR.**

ALLOW PRESSURE PUMP TO BUILD PRESSURE UP TO AT LEAST 14IN H20.

REMOVE GAS CAP.

DID PRESSURE DROP WHEN GAS CAP WAS REMOVED?

NO

CONTINUE TEST TC-187A ON THE NEXT PAGE.

YES

REINSTALL GAS CAP, BUILD PRESSURE BACK UP TO AT LEAST 14IN H20.

DISCONNECT LDP PRESSURE HOSE FROM THE LDP.

DID PRESSURE DROP WHEN HOSE WAS DISCONNECTED?

YES REPLACE LDP.*

NO

REPLACE EVAPORATIVE CANISTER.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
655

T TEST TC-187A R O U B L E C O D E T E S T S

CONTINUED REPAIRING EVAP LEAK MONITOR PINCHED HOSE

FIG. 1

656

TEST TC-187A CONTINUED - REPAIRING - EVAP LEAK MONITOR PINCHED HOSE

T R O U B L E C O D E T E S T S

TEST TC-187A CONTINUED FROM THE PREVIOUS PAGE.

REINSTALL THE GAS CAP.

MAKE SURE THE PRESSURE IS STILL AT LEAST 14IN H20.

REMOVE THE GAS TANK ROLLOVER HOSE FROM THE EVAP CANISTER.

DID THE PRESSURE DROP WHEN THE HOSE WAS DISCONNECTED? NO

YES

REPAIR THE PINCHED HOSE FROM THE GAS TANK TO THE EVAP CANISTER.*

DISCONNECT THE EVAP PURGE LINE AT THE CANISTER.

DID THE PRESSURE DROP WHEN THE HOSE WAS DISCONNECTED?

YES

REPLACE THE EVAPORATIVE CANISTER.*

NO

REPAIR THE OBSTRUCTION IN THE EVAP PURGE LINE TO THE CANISTER.*

*Perform Verification TEST VER-5A.

**Check connectors - Clean / repair as necessary.
657

T TEST TC-188A REPAIRING - O/D SWITCH PRESSED (LO) MORE THAN 5 MIN. R O Perform DTC TEST Before Proceeding U AB, AN, AND BR BODIES ZJ BODY B L E C O D E T E S T S

ZJ BODY

ALL OTHER BODIES

FIG. 1

FIG. 2

FIG. 3
658

FIG. 4

TEST TC-188A REPAIRING - O/D SWITCH PRESSED (LO) MORE THAN 5 MIN.
Perform DTC TEST Before Proceeding

T R O U B L E C O D E T E S T S

START TEST TC-188A

KEY OFF. DISCONNECT THE PCM.** SEE GENERAL INFO 4.1

MEASURE THE RESISTANCE BETWEEN THE OVERDRIVE OFF SWITCH SENSE..

CIRCUIT AND GROUND. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.O OHMS?

YES

CONTINUE TEST TC-188A ON THE FOLLOWING PAGE

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE CODE IS NOT PRESENT. FIG. 3

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY. *

NO

REFER TO FIGURE 4 FOR ADDITIONAL INFORMATION.

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
659

T TEST TC-188A CONTINUED - REPAIRING - O/D SWITCH PRESSED (LO) MORE THAN 5 MIN. R O U AB, AN, AND BR BODIES B L E C O D E T E S T S

FIG. 1
ZJ BODY

FIG. 2
660

TEST TC-188A CONTINUED - REPAIRING - O/D SWITCH PRESSED (LO) MORE THAN 5 MIN.

TEST TC-188A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE OVERDRIVE OFF SWITCH.*

T R O U B L E C O D E

MEASURE THE RESISTANCE BETWEEN THE OVERDRIVE OFF SWITCH SENSE...

CIRCUIT AND GROUND. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.O OHMS?

YES

REPAIR THE OVERDRIVE OFF SWITCH SENSE CIRCUIT SHORTED TO GROUND.*

NO

T E S T S

REPLACE THE OVERDRIVE OFF SWITCH.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
661

T TEST TC-189A REPAIRING - 1/3 O2 SENSOR HEATER FAILURE R O Perform DTC TEST Before Proceeding U B L E C O D E T E S T S

FIG. 1

662

TEST TC-189A REPAIRING - 1/3 O2 SENSOR HEATER FAILURE
Perform DTC TEST Before Proceeding

START TEST TC-189A.

WITH THE DRB, READ ALL TROUBLE CODES.

ARE THERE ANY OTHER "1/3 O2 SENSOR" RELATED TROUBLE CODES?

YES

REFER TO "DTC TEST" TO PERFORM THE APPROPRIATE OXYGEN SENSOR TEST.

T R O U B L E C O D E T E S T S

NO

TURN IGNITION ON (ENGINE OFF).

WAIT 3 MINUTES.

WITH THE DRB IN SENSORS, MONITOR THE 1/3 O2 SENSOR VOLTAGE.

WAIT FOR THE VOLTAGE READING TO STABILIZE ABOVE 4.5 VOLTS.

WITH THE DRB IN ACTUATOR TESTS, PERFORM THE O2 SENSOR HEATER TEST.

MONITOR THE 1/3 O2 SENSOR VOLTAGE FOR THREE MINUTES.

IS THE 1/3 O2 SENSOR VOLTAGE STILL ABOVE 1.0 VOLT?

YES

CONTINUE TEST TC-189A ON THE NEXT PAGE.

NO

AT THIS TIME, THE CONDITION REQUIRED TO SET THE TROUBLE CODE IS NOT PRESENT. FIG. 1

STOP ALL ACTUATOR TESTS. TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
663

T TEST TC-189A R O U B L E C O D E T E S T S

CONTINUED - REPAIRING - 1/3 O2 SENSOR HEATER FAILURE

FIG. 1

FIG. 2
664

TEST TC-189A CONTINUED - REPAIRING - 1/3 O2 SENSOR HEATER FAILURE

TEST TC-189A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE 1/3 O2 SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

T R O U B L E C O D E T E S T S

YES

REPAIR OR REPLACE AS NECESSARY.*

NO

NOTE: THE DRB IS STILL ACTUATING THE O2 SENSOR HEATER TEST.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT.*

YES

STOP ALL ACTUATOR TESTS.

USING AN OHMMETER, MEASURE THE O2 SENSOR HEATER ELEMENT. FIG. 2

IS THE RESISTANCE BETWEEN 4.0 AND 7.0 OHMS?

NO

REPLACE THE 1/3 O2 SENSOR.*

YES

USING AN OHMMETER, MEASURE FROM THE HEATER GROUND...

CIRCUIT TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN 1/3 O2 SENSOR GROUND CIRCUIT.*

YES

REPLACE THE 1/3 O2 SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
665

N TEST NTC-1A O T R O U B L E C O D E T E S T S

NO TROUBLE CODE TEST MENU

Perform DTC Test Before Proceeding. For Diesel Vehicles Perform NTC-1B.

First, check all Technical Service Bulletins and Hotline Newsletters that relate to this driveability problem. Perform corrective actions if indicated, otherwise continue. 1. NO TROUBLE CODE COMPLETE TEST (non-monitored & monitored circuits) Perform TESTS NTC-2A through NTC-18 in sequence until the driveability problem is found. NO TROUBLE CODE MENU CHECKING SECONDARY IGNITION AND TIMING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-2A CHECKING THE FUEL PRESSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-3A CHECKING COOLANT SENSOR CALIBRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-4A CHECKING THROTTLE POSITION SENSOR CALIBRATION. . . . . . . . . . . . . . . . . . . . . . . .NTC-5A CHECKING MAP SENSOR CALIBRATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-6A CHECKING FOR OXYGEN SENSOR SWITCHING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-7A CHECKING THE OXYGEN SENSOR HEATER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-8A CHECKING THE IDLE AIR CONTROL MOTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-9A CHECKING THE PARK/NEUTRAL SWITCH (AUTO ONLY) . . . . . . . . . . . . . . . . . . . . . . . .NTC-10A CHECKING THE PCM POWER AND GROUND CIRCUITS . . . . . . . . . . . . . . . . . . . . . . . .NTC-11A CHECKING THE EVAP SYSTEM (GASOLINE ENGINE). . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-12A CHECKING THE EGR SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-13A CHECKING THE ENGINE VACUUM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-14A CHECKING THE INTAKE AIR TEMP SENSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-15A CHECKING THE MINIMUM IDLE AIR FLOW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-16A CHECKING THE ENGINE MECHANICAL SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-22A 2. NO TROUBLE CODE QUICK INDIVIDUAL TEST (individual test only) If you suspect any of the above items to be the cause of the vehicle’s driveability problem, perform the associated test(s) individually. Return No Trouble Code Menu if driveability problem still exists, or perform No Trouble Code Complete Test. 3. NO TROUBLE CODE QUICK SYMPTOM TEST (symptom test only) Symptom checks cannot be used properly unless the driveability problem characteristic actually happens while the vehicle is being tested. To reduce diagnostic time, ensure that the DTC-Test and appropriate General Information sections have been reviewed before attempting to diagnose a symptom. Select the symptom that most accurately describes the vehicle’s driveability problem and then perform the test routine that pertains to this symptom. Perform each routine test in sequence until the problem is found. For definitions, see Section 12.0 in the General Information section in this manual.
SYMPTOM HARD START START AND STALL HESITATION/SAG/STUMBLE SURGE LACK OF POWER/SLUGGISH SPARK KNOCK/DETONATION CUTS OUT/MISSES BACKFIRE/POPBACK RUNS ROUGH/UNSTABLE/ERRATIC IDLE POOR FUEL ECONOMY DIAGNOSTIC TEST ROUTINE NTC-2A, 3A, 4A, 5A, 6A, 7A, 9A, 11A, 16A, 22A NTC-2A, 3A, 4A, 5A, 6A, 9A, 11A, 22A NO TROUBLE CODE COMPLETE TEST (STEP 1) NTC-2A, 3A, 4A, 5A, 6A, 7A, 9A, 11A, 12A, 13A, 22A NTC-2A, 3A, 4A, 5A, 6A, 7A, 9A, 11A, 12A, 14A, 22A NTC-2A, 3A, 4A, 5A, 6A, 7A, 9A, 11A, 13A, 22A NTC-2A, 3A, 7A, 11A, 14A, 22A NTC-2A, 3A, 6A, 7A, 11A, 14A, 22A NO TROUBLE CODE COMPLETE TEST (STEP 1) NO TROUBLE CODE COMPLETE TEST (STEP 1)

666

TEST NTC-1B NO TROUBLE CODE TEST MENU (DIESEL)
Perform DTC-Test Before Proceeding

N O T R O U B L E C O D E T E S T S

First, check all Technical Service Bulletins and Hotline Newsletters that relate to this driveability problem. Perform corrective actions indicated; otherwise continue. 1. NO TROUBLE CODE COMPLETE TEST (non-monitored & monitored circuits) Perform TESTS NTC-17A through NTC-22A in sequence until the driveability problem is found. NO TROUBLE CODE MENU CHECKING AIR INTAKE HEATER #1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-17A CHECKING AIR INTAKE HEATER #2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-18A CHECKING FUEL HEATER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-19A CHECKING THE WAIT-TO-START LAMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-20A CHECKING THE WATER-IN-FUEL LAMP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-21A CHECKING THE ENGINE MECHANICAL SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NTC-22A 2. NO TROUBLE CODE QUICK INDIVIDUAL TEST (individual test only) If you suspect any of the above items to be the cause of the vehicle’s driveability problem, perform the associated test(s) individually. Return No Trouble Code Menu if driveability problem still exists, or perform No Trouble Code Complete Test.

667

N TEST NTC-2A O T R O U B L E C O D E T E S T S

CHECKING SECONDARY IGNITION AND TIMING

Perform TEST NTC-1A Before Proceeding

FIG. 1

FIG. 2

FIG. 3
668

FIG. 4

TEST NTC-2A CHECKING SECONDARY IGNITION AND TIMING
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-2A.

ENGINE OFF.

CONNECT A SUITABLE ENGINE ANALYZER TO THE ENGINE.

ALLOW THE ENGINE TO IDLE.

NOTE: IF ENGINE WILL NOT IDLE, MAINTAIN A CONSTANT RPM ABOVE IDLE.

NOTE: SET THE SCOPE TO READ DISPLAY OR PARADE PATTERN.

FOLLOW THE EQUIPMENT MANUFACTURER’S PROCEDURE FOR PATTERN ANALYSIS. FIG. 1, 2, 3 OR 4

IS THE SECONDARY IGNITION PATTERN OK?

NO

REPAIR THE INDICATED COMPONENT IN THE SECONDARY IGNITION SYSTEM.*

YES

REMOVE ANY SPARK PLUG WIRE.

OBSERVE THE SECONDARY KV LINE.

IS THE OPEN CIRCUIT SECONDARY VOLTAGE AT LEAST 25KV?

NO

REPLACE THE ELECTRONIC IGNITION COIL.*

YES

REINSTALL THE SPARK PLUG WIRE.

NOTE: THE ENGINE TEMPERATURE MUST BE ABOVE 180F FOR THE FOLLOWING TEST.

WITH THE DRB, READ THE TOTAL TIMING ADVANCE.

RAISE THE ENGINE SPEED TO 2000 RPM.

DID THE TIMING ADVANCE CHANGE WITH RPM?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

SECONDARY IGNITION AND TIMING ADV NORMAL. TEST PASSED.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
669

N TEST NTC-3A O T R O U B L E C O D E T E S T S

CHECKING FUEL PRESSURE

Perform TEST NTC-1A Before Proceeding

FIG.1

670

TEST NTC-3A CHECKING FUEL PRESSURE
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-3A.

INSPECT ALL OF THE FUEL LINES FOR LEAKS, KINKS OR RESTRICTIONS.

ARE THERE ANY LEAKS, KINKS OR RESTRICTED LINES?

YES

WARNING: THE FUEL SYSTEM MUST BE OPENED AND MAY BE UNDER HIGH PRESSURE.

NO

WARNING: THE FUEL SYSTEM MUST BE OPENED AND MAY BE UNDER HIGH PRESSURE.

RELIEVE FUEL PRESSURE. SEE GENERAL INFO 9.0

RELIEVE FUEL PRESSURE AND REPAIR AS NECESSARY.* SEE GENERAL INFO 9.0

RECONNECT FUEL PRESSURE GAUGE TO THE FUEL SYSTEM. TURN IGNITION ON.

WITH THE DRB, ACTUATE THE FUEL SYSTEM TEST.

IS THE FUEL PRESSURE BETWEEN 44.2 AND 54.2 PSI?

YES

WITH THE DRB, STOP THE FUEL SYSTEM ACTUATION TEST.

NO

STOP ACTUATION TEST. FUEL PRESSURE IS OK AT THIS TIME. TEST PASSED.

WITH THE DRB, STOP THE FUEL SYSTEM ACTUATION TEST.

RELIEVE FUEL PRESSURE AND REPLACE FUEL PUMP MODULE.* SEE GENERAL INFO 9.0

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
671

N TEST NTC-3B O T R O U B L E C O D E T E S T S

CHECKING THE FUEL PRESSURE (CNG)

Perform TEST NTC-1A Before Proceeding

FIG. 1

FIG. 2
672

TEST NTC-3B CHECKING THE FUEL PRESSURE (CNG)
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E
YES CONTINUE TEST NTC-3B ON THE NEXT PAGE.

START TEST NTC-3B.

NOTE: THE FUEL TANK MUST BE AT LEAST 1/4 FULL TO PERFORM THE FOLLOWING TEST.

TURN IGNITION OFF. INSTALL A PRESSURE GAUGE (0-300 PSI) AT SERVICE PORT. FIG. 1

START THE ENGINE.

IS THE PRESSURE GAUGE READING BETWEEN 90 PSI AND 140 PSI?

NO

T E S T S

IS THE FUEL PRESSURE ABOVE 140 PSI?

YES

FOLLOW STEPS IN THE SERVICE MANUAL TO REPLACE DAMAGED FUEL PRESSURE REGULATOR.*

NO

REFER TO FIGURE 2 FOR POSSIBLE FUEL DELIVERY MECHANICAL PROBLEMS.

WERE ANY FUEL DELIVERY MECHANICAL PROBLEMS FOUND?

YES

REPAIR FUEL DELIVERY SYSTEM AS NECESSARY.*

NO

UNABLE TO LOCATE FUEL PROBLEM AT THIS TIME, RETURN TO NTC-1A.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
673

N TEST NTC-3B O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING THE FUEL PRESSURE (CNG)

NOTES

674

TEST NTC-3B CONTINUED - CHECKING THE FUEL PRESSURE (CNG)

N O T R O U B L E C O D E T E S T S

TEST NTC-3B CONTINUED FROM THE PREVIOUS PAGE.

WITH THE DRB, READ THE FUEL PRESSURE, AND COMPARE THE READING TO THE MECHANICAL GAUGE.

IS THE CNG FUEL PRESSURE WITHIN 5 PSI OF THE MECHANICAL FUEL PRESSURE GAUGE? NO

YES

FUEL PRESSURE IS NORMAL. TEST PASSED.

RELEASE FUEL PRESSURE. SEE GENERAL INFO 9.1

REPLACE THE CNG LOW FUEL PRESSURE SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
675

N TEST NTC-4A O T R O U B L E C O D E T E S T S

CHECKING COOLANT SENSOR CALIBRATION

Perform TEST NTC-1A Before Proceeding

676

TEST NTC-4A CHECKING COOLANT SENSOR CALIBRATION
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S
NOTE: INSPECT FOR A MECHANICAL COOLING PROBLEM BEFORE REPLACING SENSOR.

START TEST NTC-4A.

TURN IGNITION ON.

WITH THE DRB, READ THE ENGINE COOLANT TEMPERATURE SENSOR VALUE.

NOTE: IF VEHICLE TEMP IS ABOVE 180F, ALLOW ENGINE TO COOL UNTIL 150F IS REACHED.

START THE ENGINE.

WHILE MONITORING THE DRB, ALLOW ENGINE TO REACH NORMAL OPERATING TEMP. (ABOVE 180F)

WAS THE COOLANT TEMPERATURE VALUE INCREASE A SMOOTH TRANSITION?

NO

REPLACE THE COOLANT SENSOR.*

YES

DID THE COOLANT TEMPERATURE REACH 180F OR ABOVE?

NO

REPLACE THE COOLANT SENSOR.*

YES

NOTE: INSPECT FOR A MECHANICAL COOLING PROBLEM BEFORE REPLACING SENSOR.

COOLANT SENSOR OPERATING NORMALLY TEST PASSED.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
677

N TEST NTC-5A O T R O U B L E C O D E T E S T S

CHECKING THROTTLE POSITION SENSOR

Perform TEST NTC-1A Before Proceeding
ALL OTHER BODIES

ZJ BODY

678

TEST NTC-5A CHECKING THROTTLE POSITION SENSOR
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-5A.

KEY ON. WITH THE DRB, READ THE TP SENSOR VOLTAGE. THROTTLE MUST BE AGAINST STOP.

IS THE VOLTAGE 1.5 VOLT OR GREATER WITH THE THROTTLE CLOSED?

YES

IF A DIESEL CHECK ADJUSTMENT OF IDLE SPEED AND THROTTLE LINKAGE ROD PER...

NO

SERVICE MANUAL SECTION 14 BEFORE REPLACING THE THROTTLE POSITION SENSOR.*

WHILE MONITORING THE DRB, SLOWLY OPEN AND CLOSE THE THROTTLE.

IS THE VOLTAGE CHANGE SMOOTH?

NO

REPLACE THE THROTTLE POSITION SENSOR.*

YES

STOP MOVING LINKAGE. WIGGLE THE THROTTLE POSITION SENSOR CONNECTORS AND HARNESS.

MONITOR THE DRB DISPLAY.

WAS THERE ANY CHANGE IN THROTTLE POSITION SENSOR VOLTAGE WHEN WIGGLED? NO

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE VOLTAGE CHANGE.*

START THE ENGINE. WIGGLE THE THROTTLE POSITION SENSOR CONNECTORS AND HARNESS.

MONITOR THE ENGINE RPM.

WAS THERE ANY CHANGE IN ENGINE RPM WHEN WIGGLED?

YES

REPAIR THE HARNESS OR CONNECTOR THAT CAUSED THE ENGINE RPM TO CHANGE.*

NO

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TP SENSOR OPERATING NORMALLY. TEST PASSED.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
679

N TEST NTC-6A O T R O U B L E C O D E T E S T S
ZJ BODY

CHECKING MAP SENSOR

Perform TEST NTC-1A Before Proceeding

ALL OTHERS

680

TEST NTC-6A CHECKING MAP SENSOR
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E

START TEST NTC-6A.

TURN THE ENGINE OFF.

TEE IN A VACUUM GAUGE TO A MANIFOLD VACUUM SOURCE.

START THE ENGINE.

T E S T S

ALLOW THE ENGINE TO IDLE.

NOTE: IF THE ENGINE WILL NOT IDLE, MAINTAIN A CONSTANT RPM ABOVE IDLE.

USING THE DRB, READ THE MAP SENSOR VACUUM.

IS THE READING WITHIN 1" OF THE TEED-IN VACUUM GAUGE?

YES

MAP SENSOR OPERATING NORMALLY. TEST PASSED.

NO

REPLACE THE MAP SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
681

N TEST NTC-7A O T R O U B L E C O D E T E S T S
ALL CNG

CHECKING OXYGEN SENSOR SWITCHING

Perform TEST NTC-1A Before Proceeding
5.9L HD, 8.0L HD AND 8.0L CAL/MD

ALL OTHERS

682

TEST NTC-7A CHECKING OXYGEN SENSOR SWITCHING
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-7A.

NOTE: ENGINE MUST BE RUNNING AND AT NORMAL OPERATING TEMPERATURE.

NOTE: THE 1/2 AND 1/3 O2 SENSORS SHOULD SWITCH SLOWER THAN THE 1/1 OR 2/1 O2 SENSORS.

WITH THE DRB, READ THE O2 SENSOR VOLTAGES.

ARE THE O2 SENSOR VOLTAGES SWITCHING NORMALLY?

YES TEST PASSED.

NO

ARE ANY OF THE O2 SENSORS LOCKED "LEAN"?

YES

PERFORM TEST NTC-7B.

NO

TURN THE ENGINE OFF.

INSTALL A FUEL PRESSURE GAUGE TO THE FUEL LINE. USE SPECIAL TOOLS IF NECESSARY.

TURN IGNITION ON.

WITH THE DRB ACTUATE THE ASD FUEL SYSTEM TEST.

ALLOW FUEL PRESSURE TO STABILIZE.

WITH THE DRB, STOP FUEL SYSTEM TEST. MONITOR THE PRESSURE GAUGE FOR 1 MINUTE.

IS THE FUEL PRESSURE BELOW 10 PSI?

YES

IF FUEL PUMP AND LINES ARE OK, REPLACE LEAKING INJECTOR(S) AS NECESSARY.*

NO

INSPECT THE AIR FILTER AND INLET DUCTS FOR RESTRICTION(S). SEE GENERAL INFO 4.4

WERE THERE ANY RESTRICTIONS?

YES

REPAIR OR REPLACE THE AIR INLET SYSTEM AS NECESSARY.*

NO

PERFORM TEST NTC-22A.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
683

N TEST NTC-7B O T R O U B L E C O D E T E S T S

CHECKING OXYGEN SENSOR SWITCHING

Perform TEST NTC-7A Before Proceeding

FIG. 1

FIG. 2
684

TEST NTC-7B CHECKING OXYGEN SENSOR SWITCHING
Perform TEST NTC-7A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-7B.

ALLOW THE ENGINE TO IDLE.

INSPECT THE ENGINE FOR ANY ABNORMAL VACUUM CONDITIONS.

NOTE: REFER TO FIGURE 1 FOR INDICATORS OF POSSIBLE ENGINE MECHANICAL PROBLEMS.

ARE THERE ANY ABNORMAL VACUUM CONDITIONS?

YES

REPAIR ABNORMAL ENGINE VACUUM CONDITION AS REQUIRED.*

NO

WITH THE DRB, READ THE O2 SENSOR VOLTAGES.

IS THE VOLTAGE BELOW 0.10 VOLTS FOR ANY OF THE 02 SENSORS?

NO

CONTINUE TEST NTC-7B ON THE NEXT PAGE.

YES

TURN IGNITION OFF.

DISCONNECT THE O2 SENSOR CONNECTOR THAT THE VOLTAGE IS BELOW 0.10 VOLT.

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE O2 SENSOR...

SIGNAL CIRCUIT AND A GOOD GROUND. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE O2 SENSOR SIGNAL CKT FOR A SHORT TO GROUND.*

NO

REPLACE THE O2 SENSOR THAT WAS BELOW 0.10 VOLTS.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
685

N TEST NTC-7B O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING OXYGEN SENSOR SWITCHING

NOTES

686

TEST NTC-7B CONTINUED - CHECKING OXYGEN SENSOR SWITCHING

N O T R O U B L E

TEST NTC-7B CONTINUED FROM THE PREVIOUS PAGE.

TURN ENGINE OFF, IGNITION ON.

C O D E T E S T S

WITH THE DRB IN MISCELLANEOUS, RESET THE ADAPTIVE FUEL MEMORY.

START ENGINE AND LET IDLE FOR AT LEAST THREE MINUTES.

NOTE: ENGINE MUST BE RUNNING AND AT NORMAL OPERATING TEMPERATURE.

NOTE: THE 1/2 AND 1/3 O2 SENSOR SHOULD SWITCH SLOWER THAN THE 1/1 OR 2/1 O2 SENSOR.

WITH THE DRB, READ THE O2 SENSOR VOLTAGES.

ARE THE O2 SENSOR VOLTAGES SWITCHING NORMALLY?

YES TEST PASSED.

NO

PERFORM TEST NTC-22A.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
687

N TEST NTC-8A O T R O U B L E C O D E T E S T S

CHECKING THE OXYGEN SENSOR HEATER

Perform TEST NTC-1A Before Proceeding
TYPICAL CONNECTOR

FIG. 1
5.9L HD,8.0L HD AND 8.0L CAL/MD ALL OTHERS

688

TEST NTC-8A CHECKING THE OXYGEN SENSOR HEATER
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-8A.

TURN IGNITION ON. WITH THE DRB, ACTUATE THE O2 SENSOR HEATER TEST.

NOTE:USE APPROPRIATE O2 SENSOR CONNECTOR WHEN PERFORMING THIS TEST. FIG. 1

WAIT TWO MINUTES FOR THE O2 SENSOR VOLTAGES TO STABILIZE.

WITH THE DRB, READ THE O2 SENSOR VOLTAGES.

ARE ANY OF THE VOLTAGES FOR THE O2 SENSORS ABOVE 1.0 VOLT?

NO

WITH THE DRB, STOP THE ACTUATION TEST. TEST PASSED.

YES

NOTE: THE O2 SENSOR VOLTAGE STAYING ABOVE 1.0 VOLT INDICATES A PROBLEM WITH THAT SENSOR.

NOTE: THE DRB IS STILL ACTUATING THE O2 SENSOR HEATER TEST.

DISCONNECT THE O2 SENSOR CONNECTOR THAT HAS VOLTAGE ABOVE 1.0 VOLT.** SEE GENERAL INFO 4.4

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CIRCUIT AT SENSOR CONNECTOR. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT TO THE O2 SENSOR CONNECTOR.*

YES

WITH THE DRB, STOP THE ACTUATOR TEST.

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE HEATER GROUND...

CIRCUIT AND A GOOD GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN HEATER GROUND CIRCUIT TO THE O2 SENSOR.*

YES

REPLACE THE O2 SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
689

N TEST NTC-9A O T R O U B L E C O D E T E S T S

CHECKING IDLE AIR CONTROL MOTOR

Perform TEST NTC-1A Before Proceeding
AB, AN, BR, AND XJ BODIES

ZJ BODY

690

TEST NTC-9A CHECKING IDLE AIR CONTROL MOTOR
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-9A.

WITH THE ENGINE RUNNING AND AT NORMAL OPERATING TEMPERATURE,...

USING THE DRB IN ACTUATOR TESTS, SET ENGINE SPEED TO 1400 RPM.

IS THE ENGINE SPEED 1400 RPM 100 RPM?

YES

WITH THE DRB, STOP ALL TESTS. IAC MOTOR IS OPERATING OK. TEST PASSED.

NO

WITH THE DRB, STOP ALL TESTS.

INSPECT THE ENGINE FOR ANY VACUUM LEAK(S).

IS THERE ANY VACUUM LEAKS?

YES

REPAIR VACUUM LEAK(S) AS NECESSARY.*

NO

TURN ENGINE OFF.

DISCONNECT THE IDLE AIR CONTROL MOTOR CONNECTOR.** SEE GENERAL INFO 4.0

INSPECT ALL TERMINALS.

ARE ANY TERMINALS CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

CONTINUE TEST NTC-9A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
691

N TEST NTC-9A O T R O U B L E C O D E T E S T S
AB BODY

CONTINUED - CHECKING IDLE AIR CONTROL MOTOR
AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
692

FIG. 4

TEST NTC-9A CONTINUED - CHECKING IDLE AIR CONTROL MOTOR

N O T R O U B L E C O D E T E S T S
YES REPAIR THE IAC #2 DRIVER CIRCUIT SHORTED TO GROUND.*

TEST NTC-9A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE IAC MOTOR CONNECTOR.** SEE GENERAL INFO 4.0

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

USING AN OHMMETER, MEASURE BETWEEN...

IAC DRIVER #1 AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IAC #1 DRIVER CIRCUIT SHORTED TO GROUND.*

NO

USING AN OHMMETER, MEASURE BETWEEN...

IAC DRIVER #2 AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

USING AN OHMMETER, MEASURE BETWEEN...

IAC DRIVER #3 AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IAC #3 DRIVER CIRCUIT SHORTED TO GROUND.*

NO

USING AN OHMMETER, MEASURE BETWEEN...

IAC DRIVER #4 AND GROUND. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IAC #4 DRIVER CIRCUIT SHORTED TO GROUND.*

NO

CONTINUE TEST NTC-9A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
693

N TEST NTC-9A O T R O U B L E C O D E T E S T S
AB BODY

CONTINUED - CHECKING IDLE AIR CONTROL MOTOR
AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
694

FIG. 4

TEST NTC-9A CONTINUED - CHECKING IDLE AIR CONTROL MOTOR

N O T R O U B L E C O D E T E S T S

TEST NTC-9A CONTINUED FROM PREVIOUS PAGE.

TURN IGNITION ON. WITH THE DRB IN ACTUATOR TESTS, ACTUATE THE IAC STEPPER MOTOR.

NOTE: THE VOLTAGE MAY SWITCH OR REMAIN CONSTANT DURING THIS TEST.

USING A VOLTMETER, MEASURE THE IAC DRIVER #1 CIRCUIT. FIG. 1, 2, 3 OR 4

WAS THE VOLTAGE OVER 5.0 VOLTS AT ANY TIME?

NO

PERFORM TEST TC-25B.

YES

USING A VOLTMETER, MEASURE THE IAC DRIVER #2 CIRCUIT. FIG. 1, 2, 3 OR 4

WAS THE VOLTAGE OVER 5.0 VOLTS AT ANY TIME?

NO

PERFORM TEST TC-25C.

YES

USING A VOLTMETER, MEASURE THE IAC DRIVER #3 CIRCUIT. FIG. 1, 2, 3 OR 4

WAS THE VOLTAGE OVER 5.0 VOLTS AT ANY TIME?

NO

PERFORM TEST TC-25D.

YES

USING A VOLTMETER, MEASURE THE IAC DRIVER #4 CIRCUIT. FIG. 1, 2, 3 OR 4

WAS THE VOLTAGE OVER 5.0 VOLTS AT ANY TIME?

NO

PERFORM TEST TC-25E.

YES

PERFORM TEST NTC-9B.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
695

N TEST NTC-9B O T R O U B L E C O D E T E S T S
AB BODY

CHECKING IDLE AIR CONTROL MOTOR
AN AND BR BODIES

Perform TEST NTC-9A Before Proceeding

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
696

FIG. 4

TEST NTC-9B CHECKING IDLE AIR CONTROL MOTOR
Perform TEST NTC-9A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-9B.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

IS ANY TERMINAL CORRODED, DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

THE FOLLOWING STEPS ARE CHECKING FOR A SHORT BETWEEN THE DRIVER CIRCUITS.

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE ...

IAC #1 DRIVER AND #2, #3, #4 DRIVERS. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS ON ANY OF THE DRIVERS?

YES

REPAIR THE IAC DRIVER CIRCUITS, SHORTED TOGETHER.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE ...

IAC #2 DRIVER AND #3, #4 DRIVERS. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS ON ANY OF THE DRIVERS?

YES

REPAIR THE IAC DRIVER CIRCUITS, SHORTED TOGETHER.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE ...

IAC #3 DRIVER AND #4 DRIVER. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IAC DRIVER CIRCUITS, SHORTED TOGETHER.*

NO

REPLACE THE IAC MOTOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
697

N TEST NTC-10A O T R O U B L E C O D E T E S T S

CHECKING THE PARK/NEUTRAL POSITION SWITCH
AB BODY

Perform TEST NTC-1A Before Proceeding

FIG. 1
AN AND XJ BODIES BR AND ZJ BODIES

FIG. 2
698

FIG. 3

TEST NTC-10A CHECKING THE PARK/NEUTRAL POSITION SWITCH
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-10A.

WITH THE DRB, READ THE PARK/NEUTRAL SWITCH INPUT STATE.

WHILE MOVING GEAR SELECTOR FROM PARK TO 1 AND BACK TO PARK, WATCH DRB DISPLAY.

DID THE DISPLAY SHOW "P/N" AND "D/R" IN THE CORRECT POSITIONS?

YES

PARK/NEUTRAL POSITION SWITCH NORMAL. TEST PASSED.

NO

PUT THE GEAR SELECTOR IN PARK.

TURN IGNITION KEY OFF.

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

MEASURE THE RESISTANCE BETWEEN THE P/N SWITCH SENSE CKT AND GROUND. FIG. 1, 2 OR 3

OBSERVE THE OHMMETER DISPLAY WHILE MOVING GEAR SELECTOR FROM PARK TO 1 AND BACK TO PARK.

DID THE DISPLAY SWITCH FROM BELOW 10.0 OHMS TO ABOVE 10.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

DID THE DISPLAY STAY BELOW 10.0 OHMS AT ALL TIMES?

YES

REPAIR THE P/N SWITCH SENSE CKT FOR A SHORT TO GROUND.*

NO

CONTINUE TEST NTC-10A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
699

N TEST NTC-10A O T R O U B L E C O D E T E S T S
AN BODY AB BODY

CONTINUED - CHECKING THE PARK/NEUTRAL POSITION SWITCH

Perform TEST NTC-1A Before Proceeding

FIG. 1
BR BODY

FIG. 2
XJ BODY ZJ BODY

FIG. 3

FIG. 4
700

FIG. 5

TEST NTC-10A CONTINUED - CHECKING THE PARK/NEUTRAL POSITION SWITCH
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S

TEST NTC-10A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE PARK/NEUTRAL POSITION SWITCH CONNECTOR.** SEE GENERAL INFO 4.4

MEASURE THE RESISTANCE OF THE PARK/NEUTRAL SWITCH SENSE CIRCUIT...

FROM THE PCM CONNECTOR TO THE P/N SWITCH CONN. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE PARK/NEUTRAL POSITION SWITCH.*

NO

REPAIR THE OPEN P/N SWITCH SENSE CIRCUIT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
701

N TEST NTC-11A O T R O U B L E C O D E T E S T S
AN BODY

CHECKING THE PCM POWER AND GROUND CIRCUITS
AB AND BR BODIES

Perform TEST NTC-1A Before Proceeding

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
702

FIG. 4

TEST NTC-11A CHECKING THE PCM POWER AND GROUND CIRCUITS
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S
NO REPAIR THE OPEN GROUND CIRCUIT.*

START TEST NTC-11A.

KEY OFF. DISCONNECT THE BLACK POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE CAVITY A31 IN THE BLACK PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

YES

USING AN OHMMETER, MEASURE CAVITY A32 IN THE BLACK PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

USING A VOLTMETER, MEASURE CAVITY A22 IN THE BLACK PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+) CIRCUIT.*

YES

TURN THE IGNITION SWITCH ON.

USING A VOLTMETER, MEASURE CAVITY A2 IN THE BLACK PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.*

YES

RECONNECT THE BLACK POWERTRAIN CONTROL MODULE CONNECTOR.

PCM POWER AND GROUND CIRCUITS ARE NORMAL. TEST PASSED.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
703

N TEST NTC-12A O T R O U B L E C O D E T E S T S
BR BODY AB BODY

CHECKING THE EVAP SYSTEM
AN BODY
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June,1997

Perform TEST NTC-1A Before Proceeding

XJ BODY

ZJ 4.0L

ZJ 5.2L

704

TEST NTC-12A CHECKING THE EVAP SYSTEM
Perform TEST NTC-1A Before Proceeding
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

N O T R O U B L E C O D E T E S T S

START TEST NTC-12A.

NOTE: CAREFULLY INSPECT ALL VACUUM HOSES FOR PROPER ROUTING AND FOR PINCHED OR...

PLUGGED HOSES FROM THE ENGINE TO THE EVAP SOLENOID TO THE GAS TANK.

ARE ALL THE VACUUM HOSES OK?

NO

REPAIR THE VACUUM HOSES AS NECESSARY.*

YES

START THE ENGINE AND ALLOW IT TO REACH NORMAL OPERATING TEMPERATURE (170 DEG F).

TURN ENGINE OFF (IGN. OFF).

DISCONNECT THE PURGE VACUUM HOSE AT THE SOLENOID THAT GOES TO THE CANISTER.

START THE ENGINE. THERE SHOULD BE NO FLOW THE THROUGH SOLENOID FROM 1 TO 2 MINUTES.

IS THE PURGE SOLENOID ALLOWING VACUUM THROUGH THE SOLENOID WITHIN 1 MINUTE? NO

YES

CONTINUE TEST NTC-12A ON THE NEXT PAGE.

AFTER 90 SECONDS, THE PURGE SOLENOID WILL ALLOW VACUUM TO...

CYCLE INTERMITTENTLY AT A STEADY RATE.

IS THE EVAP SOLENOID ALLOWING VACUUM TO CYCLE THROUGH INTERMITTENTLY AT A STEADY RATE? YES

NO

REPLACE THE PURGE SOLENOID.*

NOTE: IN THE NEXT STEPS, DO NOT USE MORE THAN FIVE PSI.

KEY OFF, ATTEMPT TO BLOW AIR THROUGH THE VACUUM LINE THAT GOES TO THE CANISTER.

DOES THE CANISTER AND VACUUM LINE ALLOW AIR TO PASS?

YES

PURGE SOLENOID AND HOSES ARE OK. TEST PASSED.

NO

PERFORM TEST NTC-12B.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
705

N TEST NTC-12A O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING THE EVAP SYSTEM
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

TEST NTC-12A CONTINUED FROM THE PREVIOUS PAGE.

REMOVE THE PURGE SOLENOID AND TAP THE PORTS AGAINST A CLEAN, SOLID SURFACE.

DID ANY FOREIGN MATERIAL FALL OUT?

NO

REPLACE THE EVAP PURGE SOLENOID.*

YES

INSPECT LINE FROM THE PURGE SOLENOID TO THE CANISTER.

IS THE LINE DISCONNECTED, RIPPED OR CUT? YES

NO

CLEAN OUT THE LINE AND REPLACE THE EVAP PURGE SOLENOID AND CANISTER.*

REPAIR THE LINE AND REPLACE THE PURGE SOLENOID.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
706

TEST NTC-12B CONTINUED - CHECKING THE EVAP SYSTEM
1996 2.5/4.0/5.2/5.9/8.0L Jeep and Truck Engine Publication No. 81-699-96103 TSB 26-06-97 June, 1997

N O T R O U B L E C O D E T E S T S
REPAIR OR REPLACE THE VACUUM LINE.*

START TEST NTC-12B.

DISCONNECT THE VACUUM LINE AT THE CANISTER THAT GOES TO THE EVAP SOLENOID.

ATTEMPT TO BLOW AIR THROUGH THE VACUUM LINE THAT GOES TO THE CANISTER.

DOES THE VACUUM LINE ALLOW AIR TO PASS?

YES

REPLACE THE EVAPORATIVE CANISTER.*

NO

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
707

N TEST NTC-13A O T R O U B L E C O D E T E S T S

CHECKING EGR SYSTEM

Perform TEST NTC-1B Before Proceeding

TYPICAL CONFIGURATION

FIG. 1
708

TEST NTC-13A CHECKING EGR SYSTEM
Perform TEST NTC-1B Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-13A.

INSPECT THE CONDITION OF ALL EGR HOSES AND ROUTING. FIG. 1

ARE THERE ANY MISROUTED OR DAMAGED HOSES?

YES

REPAIR HOSES AS NECESSARY.*

NO

IS THIS VEHICLE EQUIPPED WITH A DIESEL ENGINE?

NO

PERFORM TEST NTC-13B.

YES

START ENGINE AND LET IDLE.

WITH THE DRB IN EGR SYSTEM TEST PRESS #2 TO BLOCK EGR FLOW.

MONITOR IAT TEMPERATURE UNTIL TEMPERATURE STABILIZES.

ACTUATE THE EGR SOLENOID AND ALLOW EGR TO FLOW. MONITOR INTAKE AIR TEMPERATURE.

DID THE INTAKE AIR TEMPERATURE RISE AFTER THE EGR WAS ACTUATED?

NO

CONTINUE TEST NTC-13A ON THE NEXT PAGE.

YES

USING THE SCHEMATIC AS A GUIDE, INSPECT THE WIRING AND CONNECTORS.

WERE ANY PROBLEMS FOUND?

YES

REPAIR AS NECESSARY.*

NO

TEST COMPLETE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
709

N TEST NTC-13A O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING EGR SYSTEM

TYPICAL CONFIGURATION

FIG. 1

710

TEST NTC-13A CONTINUED - CHECKING EGR SYSTEM

N O T R O U B L E C O D E T E S T S

TEST NTC-13A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE EGR SOLENOID VACUUM SUPPLY AT THE EGR SOLENOID. FIG. 1

IS VACUUM PRESENT AT THE SOLENOID?

NO

REPAIR THE VACUUM SUPPLY TO THE EGR SOLENOID.*

YES

RECONNECT THE EGR SOLENOID VACUUM SUPPLY AT THE EGR SOLENOID. FIG. 1

DISCONNECT THE EGR VACUUM LINE AT THE EGR SOLENOID THAT GOES TO THE EGR.

EGR STATUS SHOULD STILL DISPLAY FLOW.

IS THE EGR SOLENOID ALLOWING VACUUM TO PASS THROUGH?

NO

REPLACE THE EGR SOLENOID.*

YES

RECONNECT THE EGR VACUUM LINE AT THE EGR SOLENOID THAT GOES TO THE EGR.

DISCONNECT THE VACUUM LINE AT THE EGR. FIG. 1

IS VACUUM PRESENT AT THE EGR?

NO

REPAIR VACUUM HOSE OR CHECK VALVE AS NECESSARY.*

YES

STOP EGR SYSTEMS TESTS AND TURN ENGINE OFF.

REMOVE EGR VALVE AND CONNECT A HAND OPERATED VACUUM PUMP TO FITTING. FIG. 1

SLOWLY APPLY 10 INCHES OF VACUUM TO EGR VALVE AND MONITOR POPPET VALVE.

DID POPPET VALVE START TO OPEN AT 10 INCHES OF VACUUM?

NO

REPLACE THE EGR VALVE.*

YES

ENSURE THERE IS NO CARBON BUILD UP IN EGR TUBE, INTAKE AND EXHAUST MANIFOLDS AND RETEST EGR.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
711

N TEST NTC-13B O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING EGR SYSTEM

Perform TEST NTC-13A Before Proceeding
TYPICAL CONFIGURATION

FIG. 1

712

TEST NTC-13B CONTINUED - CHECKING EGR SYSTEM
Perform TEST NTC-13A Before Proceeding

N O T R O U B L E C O D E

START TEST NTC-13B.

DISCONNECT THE VACUUM LINE TO THE EGR VALVE. FIG. 1

CONNECT A HAND HELD VACUUM SUPPLY TO THE EGR VALVE.

T E S T S
WHILE SLOWLY APPLYING VACUUM TO THE EGR VALVE, LISTEN FOR AN ENGINE SPEED CHANGE. DID THE ENGINE SPEED STAY THE SAME? YES INSPECT PASSAGES, IF OK, REPLACE THE EGR VALVE ASSEMBLY.*

START ENGINE AND LET IDLE.

NO

IGNITION KEY OFF.

APPLY 10" OF VACUUM AND HOLD FOR 30 SECONDS.

DID THE VACUUM HOLD FOR 30 SECONDS?

NO

REPLACE THE EGR VALVE ASSEMBLY.*

YES

EGR SYSTEM NORMAL. TEST PASSED.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
713

N TEST NTC-14A O T R O U B L E C O D E T E S T S

CHECKING THE ENGINE VACUUM

Perform TEST NTC-1A Before Proceeding

FIG. 1

FIG. 2
714

TEST NTC-14A CHECKING THE ENGINE VACUUM
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E

START TEST NTC-14A.

CONNECT A VACUUM GAUGE TO THE ENGINE.

C O D E T E S T S

ALLOW THE ENGINE TO IDLE.

NOTE: A NORMAL VACUUM READING WILL VARY ACCORDING TO THE ALTITUDE. FIG. 1

WHILE MONITORING THE VACUUM GAUGE, SNAP THE THROTTLE OPEN A FEW TIMES.

OBSERVE THE VACUUM GAUGE READINGS. FIG. 2

ARE THE VACUUM GAUGE READINGS NORMAL?

NO

PERFORM TEST NTC-22A.

YES

ENGINE VACUUM NORMAL. TEST PASSED.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
715

N TEST NTC-15A O T R O U B L E C O D E T E S T S

CHECKING THE INTAKE AIR TEMP SENSOR

Perform TEST TC-118A, NTC-1A OR NTC-14A Before Proceeding
AB AND AN 3.9L, BR 5.2L AND 5.9L

FIG. 1
AN 2.5L, XJ, AND 4.0L ZJ AN 5.2L

FIG. 2
BR 8.0L ZJ 5.2L

FIG. 3

FIG. 4
716

FIG. 5

TEST NTC-15A CHECKING THE INTAKE AIR TEMP SENSOR
Perform TEST TC-118A, NTC-1A OR NTC-14A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-15A

NOTE: MAKE SURE THE IGNITION KEY IS ON AT THIS TIME (ENGINE OFF).

CAUTION: DO NOT ALLOW MORE THAN 5 MINUTES DELAY BETWEEN NEXT STEPS.

WITH THE DRB, READ THE INTAKE AIR TEMPERATURE (IAT) SENSOR AND RECORD THE READING.

KEY OFF. REMOVE THE MAP SENSOR. FIG. 1, 2, 3, 4 OR 5

USING A TEMP PROBE, MEASURE THE IAT INSIDE MAP SENSOR OPENING. FIG. 1, 2, 3, 4 OR 5

IS THE IAT RECORDING WITHIN 10 DEGREES OF THE PROBE READING?

NO

REPLACE THE IAT SENSOR.*

YES

RECONNECT THE MAP SENSOR. IAT SENSOR TEST PASSED.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
717

N TEST NTC-16A O T R O U B L E C O D E T E S T S

CHECKING MINIMUM AIR FLOW

Perform TEST NTC-1A Before Proceeding

FIG. 1

718

TEST NTC-16A CHECKING MINIMUM AIR FLOW
Perform TEST NTC-1A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-16A.

IS THIS VEHICLE A 2.5L OR 4.0L ENGINE?

YES

2.5L AND 4.0L ENGINES DO NOT HAVE A MINIMUM IDLE AIR FLOW TEST.

NO

REMOVE THE AIR CLEANER.

REMOVE THE VACUUM LINE FROM THE PCV VALVE...

AND INSTALL THE 0.185 ORIFICE INTO THE VACUUM LINE. FIG. 1

DISCONNECT THE 3/16" EVAPORATIVE EMISSION HOSE ON THE SIDE OF THE THROTTLE BODY...

AND CAP THE THROTTLE BODY NIPPLE.

START ENGINE. ALLOW ENGINE TO REACH NORMAL OPERATING TEMPERATURE. (ABOVE 180F)

WITH THE DRB, ACTUATE MINIMUM IDLE AIR FLOW.

WAIT FOR THE SYSTEM TO STABILIZE.

IS THE ENGINE RPM BETWEEN 500 AND 900 RPM?

YES

MINIMUM IDLE AIR FLOW NORMAL. TEST PASSED.

NO

STOP ACTUATION TEST. TURN ENGINE OFF. USING AN APPROVED CLEANER, CLEAN THE THROTTLE BODY.

START THE ENGINE. WITH THE DRB, ACTUATE THE MINIMUM AIR FLOW.

IS THE ENGINE RPM BETWEEN 500 AND 900?

YES REPAIR COMPLETE.*

NO

NOTE: A VACUUM LEAK MAY CAUSE THE IAC MOTOR NOT TO PERFORM CORRECTLY.

REPLACE THE THROTTLE BODY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
719

N TEST NTC-17A O T R O U B L E C O D E T E S T S

CHECKING THE AIR INTAKE HEATER #1

Perform TEST NTC-1B Before Proceeding

FIG. 1
720

TEST NTC-17A CHECKING THE AIR INTAKE HEATER #1
Perform TEST NTC-1B Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-17A.

CAUTION: AIR INTAKE HEATER ACTUATION TIME MUST BE KEPT AT A MINIMUM DUE TO HIGH CURRENT DRAW.

USING A VOLTMETER, MEASURE THE BATTERY B(+) TERMINAL AND RECORD THE RESULT.

WITH THE DRB, ACTUATE #1 AIR INTAKE HEATER.

WHILE ACTUATING, USE A VOLTMETER AND MEASURE THE BATTERY B(+) TERMINAL.

STOP ACTUATION TEST.

DID THE BATTERY VOLTAGE DROP 0.5 VOLT OR MORE DURING ACTUATION TEST? NO

YES

AIR INTAKE HEATER #1 OPERATION IS NORMAL. TEST PASSED.

DID THE AIR INTAKE HEATER RELAY CLICK WHEN ACTUATED?

YES

PERFORM TEST NTC-17B.

NO

DISCONNECT THE FUSED IGNITION SWITCH OUTPUT CIRCUIT AT HEATER RLY #1 CAV.2 FIG. 1

USING A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CIRCUIT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT TO RELAY.*

YES

RECONNECT THE FUSED IGNITION SWITCH OUTPUT CIRCUIT.

DISCONNECT THE AIR INTAKE HEATER RELAY #1 CONTROL CIRCUIT, CAVITY 1 FIG. 1

CONNECT ONE END OF A JUMPER WIRE TO THE OPEN RELAY TERMINAL AND BRIEFLY TAP...

THE OTHER END OF THE JUMPER WIRE TO GROUND.

DID THE AIR INTAKE HEATER RELAY CLICK?

NO

REPLACE THE AIR INTAKE HEATER RELAY #1.*

YES

CONTINUE TEST NTC-17A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
721

N TEST NTC-17A O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING THE AIR INTAKE HEATER #1

FIG. 1

722

TEST NTC-17A CONTINUED - CHECKING THE AIR INTAKE HEATER #1

N O T R O U B L E

TEST NTC-17A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE BLACK CONNECTOR.** SEE GENERAL INFO 4.1

C O D E T E S T S

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE AIR INTAKE HEATER RELAY #1...

CONTROL CIRCUIT FROM THE PCM TO THE RELAY. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN AIR INTAKE HEATER RELAY #1 CONTROL CIRCUIT.*

YES

USING AN OHMMETER, MEASURE AIR INTAKE HEATER RLY #1 CONTROL CKT AT PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE AIR INTAKE HEATER RELAY #1 CONTROL CIRCUIT FOR A SHORT TO GROUND.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
723

N TEST NTC-17B O T R O U B L E C O D E T E S T S

CHECKING THE AIR INTAKE HEATER #1

Perform TEST NTC-17A Before Proceeding

FIG. 1

FIG. 2
724

TEST NTC-17B CHECKING THE AIR INTAKE HEATER #1
Perform TEST NTC-17A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-17B.

USING A VOLTMETER, MEASURE THE B(+) CIRCUIT FOR AIR INTAKE HEATER #1. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN B(+) CIRCUIT BETWEEN THE BATTERY AND INTAKE HEATER RELAY #1.*

YES

WITH THE DRB, ACTUATE THE AIR INTAKE HEATER RELAY #1.

USING A VOLTMETER, MEASURE THE AIR INTAKE HEATER RELAY #1 OUTPUT CIRCUIT. FIG. 2

IS THE VOLTAGE ABOVE 9.0 VOLTS?

NO

REPAIR THE OPEN AIR INTAKE HEATER RELAY #1 OUTPUT CIRCUIT.*

YES

REPLACE THE AIR INTAKE HEATER ELEMENT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
725

N TEST NTC-18A O T R O U B L E C O D E T E S T S

CHECKING THE AIR INTAKE HEATER #2

Perform TEST NTC-1B Before Proceeding

FIG. 1
726

TEST NTC-18A CHECKING THE AIR INTAKE HEATER #2
Perform TEST NTC-1B Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-18A.

CAUTION: AIR INTAKE HEATER ACTUATION TIME MUST BE KEPT AT A MINIMUM DUE TO HIGH CURRENT DRAW.

USING A VOLTMETER, MEASURE THE BATTERY B(+) TERMINAL AND RECORD THE RESULT.

WITH THE DRB, ACTUATE #2 AIR INTAKE HEATER.

WHILE ACTUATING, MEASURE THE BATTERY B(+) TERMINAL.

STOP ACTUATION TEST.

DID THE BATTERY VOLTAGE DROP 0.5 VOLT OR MORE DURING ACTUATION TEST? NO

YES

AIR INTAKE HEATER #2 OPERATION IS NORMAL. TEST PASSED.

DID THE AIR INTAKE HEATER RELAY CLICK WHEN ACTUATED?

YES

PERFORM TEST NTC-18B.

NO

DISCONNECT THE FUSED IGNITION SWITCH OUTPUT CIRCUIT AT HEATER RLY #2 CAV.4 FIG.1

USING A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CIRCUIT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT TO RELAY.*

YES

RECONNECT THE FUSED IGNITION SWITCH OUTPUT CIRCUIT.

DISCONNECT THE AIR INTAKE HEATER RELAY #2 CONTROL CIRCUIT, CAVITY 3. FIG. 1

CONNECT ONE END OF A JUMPER WIRE TO THE OPEN RELAY TERMINAL AND BRIEFLY TAP...

THE OTHER END OF THE JUMPER WIRE TO GROUND.

DID THE AIR INTAKE HEATER RELAY CLICK?

NO

REPLACE THE AIR INTAKE HEATER RELAY #2.*

YES

CONTINUE TEST NTC-18A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
727

N TEST NTC-18A O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING THE AIR INTAKE HEATER #2

FIG. 1

728

TEST NTC-18A CONTINUED - CHECKING THE AIR INTAKE HEATER #2

N O T R O U B L E

TEST NTC-18A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE BLACK CONNECTOR.** SEE GENERAL INFO 4.1

C O D E T E S T S

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE AIR INTAKE HEATER RELAY #2...

CONTROL CIRCUIT FROM THE PCM TO THE RELAY. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN AIR INTAKE HEATER RELAY #2 CONTROL CIRCUIT.*

YES

USING AN OHMMETER, MEASURE AIR INTAKE HEATER RLY #2 CONTROL CKT AT PCM TO GROUND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE AIR INTAKE HEATER RELAY #2 CONTROL CIRCUIT FOR A SHORT TO GROUND.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
729

N TEST NTC-18B O T R O U B L E C O D E T E S T S

CHECKING THE AIR INTAKE HEATER #2

Perform TEST NTC-18A Before Proceeding

FIG. 1

FIG. 2
730

TEST NTC-18B CHECKING THE AIR INTAKE HEATER #2
Perform TEST NTC-18A Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-18B.

USING A VOLTMETER, MEASURE THE B(+) CIRCUIT FOR AIR INTAKE HEATER #2. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN B(+) CIRCUIT BETWEEN THE BATTERY AND INTAKE HEATER RELAY #2.*

YES

WITH THE DRB, ACTUATE THE AIR INTAKE HEATER RELAY #2.

USING A VOLTMETER, MEASURE THE AIR INTAKE HEATER RELAY #2 OUTPUT CIRCUIT. FIG. 2

WAS THE VOLTAGE ABOVE 9.0 VOLTS?

NO

REPAIR THE OPEN AIR INTAKE HEATER RELAY #2 OUTPUT CIRCUIT.*

YES

REPLACE THE AIR INTAKE HEATER ELEMENT.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
731

N TEST NTC-19A O T R O U B L E C O D E T E S T S

CHECKING THE FUEL HEATER

Perform TEST NTC-1B Before Proceeding

FIG. 1

FIG. 2
732

TEST NTC-19A CHECKING THE FUEL HEATER
Perform TEST NTC-1B Before Proceeding

N O T R O U B L E C O D E
DID THE RELAY CLICK? YES CONTINUE TEST NTC-19A ON THE NEXT PAGE.

START TEST NTC-19A.

TURN IGNITION ON.

NOTE: TO HEAR CLICK IN THE NEXT STEP. IT MAY BE NECESSARY TO DISCONNECT THE RELAY MORE THAN ONCE.

WHILE LISTENING FOR THE RELAY TO CLICK, DISCONNECT THE FUEL HEATER RLY.** FIG. 1

NO

T E S T S

WITH A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CIRCUIT. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT.*

YES

TURN IGNITION OFF.

WITH AN OHMMETER, MEASURE THE FUEL HEATER RELAY GROUND CIRCUIT. FIG. 2

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN FUEL HEATER RELAY GROUND CIRCUIT.*

NO

REPLACE THE FUEL HEATER RELAY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
733

N TEST NTC-19A O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING THE FUEL HEATER RELAY

FIG. 1

FIG. 2

FIG. 3

FIG. 4
734

FIG. 5

TEST NTC-19A CONTINUED - CHECKING THE FUEL HEATER RELAY

N O T R O U B L E C O D E T E S T S

TEST NTC-19A CONTINUED FROM THE PREVIOUS PAGE.

WITH A VOLTMETER, MEASURE THE FUSED B(+) IN HEATER RELAY CONNECTOR. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+) CIRCUIT.*

YES

IGNITION OFF. DISCONNECT THE FUEL HEATER ELECTRICAL CONNECTOR.** FIG. 2

WITH AN OHMMETER, MEASURE THE FUEL HEATER GROUND CIRCUIT. FIG. 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN FUEL HEATER GROUND CIRCUIT.*

YES

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE FUEL HEATER RELAY OUTPUT CIRCUIT...

FROM THE RELAY TO THE HEATER CONNECTOR. FIG. 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN FUEL HEATER RELAY OUTPUT CIRCUIT.*

NO

DISCONNECT FUEL HEATER ELEMENT CONNECTOR.** INSPECT ALL TERMINALS. FIG. 2

IS ANY TERMINAL DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR THE TERMINAL(S) FOR DAMAGE, PUSHOUT, OR MISWIRING.*

NO

NOTE: THE FUEL HEATER TEMPERATURE MUST BE BELOW 40F FOR THE NEXT STEP.

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE FUEL HEATER. FIG. 2 AND 5

IS THE RESISTANCE ABOVE 10.0 OHMS?

NO

THE NO START CONDITION IS DUE TO A MECHANICAL PROBLEM. SEE SERVICE MANUAL FOR REPAIRS.

YES

REPLACE THE FUEL HEATER.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
735

N TEST NTC-20A O T R O U B L E C O D E T E S T S

CHECKING THE WAIT-TO-START LAMP

Perform TEST NTC-1B Before Proceeding

736

TEST NTC-20A CHECKING THE WAIT-TO-START LAMP
Perform TEST NTC-1B Before Proceeding

N O T R O U B L E C O D E T E S T S

START TEST NTC-20A.

IS THE VEHICLE SYMPTOM PROBLEM WITH WAIT-TO-START LAMP?

NO TEST PASSED.

YES

WHILE WATCHING THE WAIT-TO-START LAMP TURN IGNITION KEY ON.

DID THE WAIT-TO-START LAMP LIGHT?

NO

CONTINUE TEST NTC-20A ON THE NEXT PAGE.

YES

DID THE WAIT-TO-START LAMP STAY ON ALL THE TIME?

NO

WAIT-TO-START LAMP OPERATING NORMALLY. TEST PASSED.

YES

KEY OFF, DISCONNECT POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL INFO 4.1

WHILE WATCHING THE WAIT-TO-START LAMP, TURN IGNITION KEY ON.

DID WAIT-TO-START LAMP LIGHT?

YES

REPAIR DIESEL WAIT-TO-START LAMP DRIVER CIRCUIT FOR A SHORT TO GROUND.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
737

N TEST NTC-20A O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING THE WAIT-TO-START LAMP

FIG. 1

FIG. 2
738

TEST NTC-20A CONTINUED - CHECKING THE WAIT-TO-START LAMP

N O T R O U B L E C O D E T E S T S

TEST NTC-20A CONTINUED FROM THE PREVIOUS PAGE.

TURN IGNITION OFF.

DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL INFO 4.1

TURN IGNITION ON.

USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE WAIT-TO-START LAMP DRIVER AT THE PCM. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

DISCONNECT THE WAIT-TO-START LAMP CONNECTOR.** SEE GENERAL INFO 4.8

VERIFY THE LAMP CONDITION.

NO IS THE LAMP OK?

REPLACE THE WAIT-TO-START LAMP.*

YES

REINSTALL THE WAIT-TO-START LAMP. KEY ON.

BACKPROBE THE FUSED IGNITION SWITCH OUTPUT CKT AT THE MESSAGE CENTER CONN. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.* TO MESSAGE CENTER.

YES

CONNECT A JUMPER BETWEEN MESSAGE CENTER CONNECTOR AND A GOOD GROUND. FIG. 2

DID THE WAIT-TO-START LAMP ILLUMINATE?

YES

REPAIR THE OPEN WAIT-TO-START LAMP DRIVER CIRCUIT.* PCM TO MESSAGE CENTER.

NO

REPLACE THE MESSAGE CENTER PRINTED CIRCUIT ASSEMBLY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
739

N TEST NTC-21A O T R O U B L E C O D E T E S T S

CHECKING THE WATER-IN-FUEL LAMP & SENSOR

Perform TEST NTC-1B Before Proceeding

FIG. 1
740

TEST NTC-21A CHECKING THE WATER-IN-FUEL LAMP & SENSOR
Perform TEST NTC-1B Before Proceeding

N O T R O U B L E

START TEST NTC-21A.

IS THE VEHICLE SYMPTOM PROBLEM WITH WATER-IN-FUEL LAMP?

NO TEST PASSED.

YES

C O D E T E S T S

DISCONNECT THE WATER-IN-FUEL SENSOR CONNECTOR.** SEE GENERAL INFO 4.4

GROUND THE WATER-IN-FUEL SENSOR SIGNAL CIRCUIT. FIG. 1

IGNITION KEY OFF, THEN IGNITION KEY ON, TO RECYCLE LAMP.

IS THE WATER-IN-FUEL LAMP ILLUMINATED?

YES

PERFORM TEST NTC-21B.

NO

IGNITION KEY OFF.

DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL INFO 4.1

CONTINUE TEST NTC-21A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
741

N TEST NTC-21A O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING THE WATER-IN-FUEL LAMP & SENSOR

FIG. 1

FIG. 2
742

TEST NTC-21A CONTINUED - CHECKING THE WATER-IN-FUEL LAMP & SENSOR

N O T R O U B L E C O D E

TEST NTC-21A CONTINUED FROM THE PREVIOUS PAGE.

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE ACROSS THE WATER-IN-FUEL SENSE CKT FROM THE PCM TO THE WIF CONNECTOR. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN WATER-IN-FUEL SENSE CIRCUIT.*

YES

T E S T S

TURN IGNITION ON.

USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE WATER-IN-FUEL LAMP DRIVER CIRCUIT, AT THE PCM. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

CONTINUE TEST NTC-21A ON THE NEXT PAGE.

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
743

N TEST NTC-21A O T R O U B L E C O D E T E S T S

CONTINUED - CHECKING THE WATER-IN-FUEL LAMP & SENSOR

FIG. 1

744

TEST NTC-21A CONTINUED - CHECKING THE WATER-IN-FUEL LAMP & SENSOR

N O T R O U B L E C O D E

TEST NTC-21A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE WATER-IN-FUEL LAMP.** SEE GENERAL INFO 4.8

VERIFY LAMP CONDITION.

NO IS THE LAMP OK?

REPLACE THE WATER-IN-FUEL LAMP.*

YES

T E S T S

RE-INSTALL THE LAMP.

BACKPROBE THE FUSED IGN. SWITCH OUTPUT CKT. AT MESSAGE CTR CONN. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT CIRCUIT.*

YES

CONNECT A JUMPER WIRE FROM THE LAMP DRIVER TO GROUND. FIG. 1

DID THE WATER-IN-FUEL LAMP ILLUMINATE?

NO

REPAIR THE OPEN WATER-IN-FUEL DRIVER CIRCUIT.*

YES

REPLACE THE MESSAGE CENTER PRINTED CIRCUIT ASSEMBLY.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
745

N TEST NTC-21B O T R O U B L E C O D E T E S T S

CHECKING THE WATER-IN-FUEL LAMP & SENSOR

Perform TEST NTC-21A Before Proceeding

FIG. 1
746

TEST NTC-21B CHECKING THE WATER-IN-FUEL LAMP & SENSOR
Perform TEST NTC-21A Before Proceeding

N O T R O U B L E C O D E

START TEST NTC-21B.

TURN IGNITION OFF. DISCONNECT THE JUMPER WIRE.

T E S T S
IS THE RESISTANCE ABOVE 5.0 OHMS? YES REPAIR THE OPEN SENSOR GROUND CIRCUIT.*

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE SENSOR GROUND CIRCUIT AT WATER-IN-FUEL CONNECTOR. FIG. 1

NO

REPLACE THE WATER-IN-FUEL SENSOR.*

*Perform Verification TEST VER-2A.

**Check connectors - Clean / repair as necessary.
747

N TEST NTC-22A O T R O U B L E C O D E T E S T S

CHECKING THE ENGINE MECHANICAL SYSTEMS

Perform TEST NTC-1A or NTC-21A Before Proceeding

The components and systems that you have checked before this are operating properly. Here are additional non-monitored components or systems to check, that could cause a driveability problem. 1. DISTRIBUTOR POSITION − must be within specifications 2. ENGINE VACUUM − must be at least 13 inches in neutral (see below) † 3. ENGINE VALVE TIMING − must be within specifications 4. ENGINE COMPRESSION − must be within specifications 5. ENGINE EXHAUST SYSTEM − must be free of any restrictions 6. ENGINE PCV SYSTEM − must flow freely 7. ENGINE DRIVE SPROCKET − must be properly positioned 8. TORQUE CONVERTER STALL SPEED − must be within specifications (auto only) 9. POWER BRAKE BOOSTER − no internal vacuum leaks 10. FUEL − must be free of contamination 11. FUEL INJECTOR − plugged or restricted injector; control wire not connected to correct injector NOTE: If you came to this test from the oxygen sensor, and the rich or lean condition is not caused by one of the first items above, replace the powertrain control module and perform TEST VER-2A (Road Test Verification). Checking Distributor Position With DRB Connect the DRB to the data link connector and select SET SYNC from the menu. WARNING: The following test will be performed with the engine running: avoid contact with rotating components. Start the engine and observe the DRB display. When the distributor is correctly positioned, the IN RANGE message should appear along with 0°. If the distributor needs to be adjusted, loosen the distributor hold-down clamp bolt. Rotate the distributor until reading is as close as to 0° as possible and the IN RANGE message displayed. Tighten the clamp bolt to 22.5 N⅐m (200 in. lbs.) torque. NOTE: Setting the distributor position does not adjust the ignition timing. Ignition timing values are determined by the powertrain control module. † The readings below are only indicators of possible mechanical engine problems.

748

TEST NTC-22B CHECKING THE ENGINE MECHANICAL SYSTEMS (Diesel)
Perform TEST NTC-22A Before Proceeding

N O T R O U B L E C O D E T E S T S

The components and systems that you have checked before this are operating properly. Here are additional non-monitored components or systems to check, that could cause a driveability problem. 1. FUEL INJECTION PUMP − malfunction, or not adjusted properly or incorrect pump timing. 2. AIR IN FUEL SYSTEM 3. RESTRICTED OR DAMAGED INJECTOR NOZZLE 4. IMPROPER FUEL 5. CLOGGED FUEL FILTER 6. RESTRICTED OR BLOCKED FUEL INJECTION LINES 7. LEAKING INJECTION LINES, DAMAGED LINES OR LOOSE CONNECTIONS 8. EMPTY FUEL TANK OR FUEL TANK VENT BLOCKED 9. CLOGGED OR RESTRICTED AIR FILTER 10. INTERCOOLER INTERNALLY BLOCKED OR LEAKING 11. LOW OR UNEVEN ENGINE COMPRESSION 12. LOW IDLE MISADJUSTED 13. CONTROL LEVER NOT GOING TO FULL THROTTLE POSITION

749

S TEST SC-1A CHECKING THE SPEED CONTROL OPERATION P E Perform DTC TEST Before Proceeding E AB, AN AND XJ BODIES D C O N T R O L T E S T S
BR BODY

ZJ BODY

750

TEST SC-1A

CHECKING THE SPEED CONTROL OPERATION

Perform DTC TEST Before Proceeding

S P E E D C O N T R O L

START TEST SC-1A.

START ENGINE.

KEY ON, WITH THE DRB, MONITOR THE SPEED CONTROL SWITCH INPUTS.

WHILE OBSERVING DISPLAY, PRESS THE SPEED CONTROL "ON" SWITCH.

DOES THE DRB SHOW SPEED CONTROL SWITCH "ON"?

NO

PERFORM TEST SC-2A.

YES

T E S T S

WHILE OBSERVING THE DISPLAY, PRESS THE BRAKE PEDAL SEVERAL TIMES.

DOES THE DRB SHOW BRAKE SWITCH "PRESSED" AND "RELEASED"?

NO

PERFORM TEST SC-3A.

YES

WHILE OBSERVING THE DISPLAY, MOVE THE GEAR SELECTOR TO DRIVE.

DOES THE DRB SHOW THE PARK/NEUTRAL SWITCH IN "DRIVE/REVERSE"?

NO

PERFORM TEST SC-4A.

YES

CONTINUE TEST SC-1A ON THE NEXT PAGE.

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
751

S TEST SC-1A P E E D C O N T R O L T E S T S

CONTINUED - CHECKING THE SPEED CONTROL OPERATION

NOTES

752

TEST SC-1A

CONTINUED - CHECKING THE SPEED CONTROL OPERATION

S P E E D C O N T R O L T E S T S

TEST SC-1A CONTINUED FROM THE PREVIOUS PAGE.

WHILE OBSERVING THE DISPLAY, PRESS THE SET SWITCH SEVERAL TIMES.

DOES THE DRB SHOW THE SET SWITCH "PRESSED" AND "RELEASED"?

NO

REPLACE THE SPEED CONTROL SWITCH.*

YES

WHILE OBSERVING THE DISPLAY, PRESS THE RESUME SWITCH SEVERAL TIMES.

DOES THE DRB SHOW THE RESUME SWITCH "PRESSED" AND "RELEASED"? YES

NO

REPLACE THE SPEED CONTROL SWITCH.*

WHILE OBSERVING THE DISPLAY, PRESS THE CANCEL SWITCH SEVERAL TIMES. (ZJ BODY ONLY)

DOES THE DRB SHOW THE CANCEL SWITCH "PRESSED" AND "RELEASED"? YES

NO

REPLACE THE SPEED CONTROL SWITCH.*

CONTINUE TEST SC-1A ON THE NEXT PAGE.

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
753

S TEST SC-1A P E E D C O N T R O L T E S T S

CONTINUED - CHECKING THE SPEED CONTROL OPERATION

FIG. 1

754

TEST SC-1A

CONTINUED - CHECKING THE SPEED CONTROL OPERATION

S P E E D
REPAIR AS NECESSARY.*

TEST SC-1A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE SPEED CONTROL SERVO CONNECTOR.** SEE GENERAL INFO 4.2

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED?

YES

NO

WITH AN OHMMETER, MEASURE THE GROUND CIRCUIT FOR RESISTANCE. FIG. 1

C O N T R O L T E S T S

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN GROUND CIRCUIT.*

YES

KEY ON. WITH THE DRB, ACTUATE THE SPEED CONTROL VENT SOLENOID.

WITH A VOLTMETER, MEASURE THE SWITCHED SC POWER SUPPLY CIRCUIT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

PERFORM TEST SC-1B

YES

RECONNECT THE SPEED CONTROL SERVO CONNECTOR. START ENGINE, ALLOW TO IDLE 1 MINUTE.

TURN ENGINE OFF, (IGNITION ON) WITH THE DRB, ACTUATE THE SPEED CONTROL SERVO SOLENOIDS.

DOES THE THROTTLE OPEN AND CLOSE?

YES

PERFORM TEST SC-5A.

NO

KEY OFF, DISCONNECT THE VACUUM SUPPLY TO THE SPEED CONTROL SERVO.

ATTACH A VACUUM GAUGE TO THE DISCONNECTED HOSE. START ENGINE.

DOES THE VACUUM GAUGE READ MANIFOLD VACUUM?

NO

REPAIR THE VACUUM SUPPLY FOR A LEAK OR RESTRICTION.*

YES

TURN ENGINE OFF, OBSERVE VACUUM GAUGE FOR 10 SECONDS.

DOES THE VACUUM HOLD FOR AT LEAST 10 SECONDS?

NO

REPLACE THE VACUUM RESERVOIR.*

YES

CONTINUE TEST SC-1A ON THE NEXT PAGE.

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
755

S TEST SC-1A CONTINUED - CHECKING THE SPEED CONTROL OPERATION P E E AB, AN AND XJ BODIES BR BODY D C O N T R O L T E S T S
ZJ BODY AB, AN AND XJ BODIES

FIG. 1
BR BODY ZJ BODY

FIG. 2
756

FIG. 3

TEST SC-1A

CONTINUED - CHECKING THE SPEED CONTROL OPERATION

S P E E D
REPAIR AS NECESSARY.*

TEST SC-1A CONTINUED FROM THE PREVIOUS PAGE.

INSPECT THE THROTTLE CABLE.

IS THE CABLE DISCONNECTED OR DAMAGED?

YES

NO

C O N T R O L T E S T S

KEY OFF. DISCONNECT THE SPEED CONTROL SERVO 4 WAY CONNECTOR.** SEE GENERAL INFO 4.2

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

WITH AN OHMMETER, MEASURE THE RESISTANCE OF THE...

SPEED CONTROL VACUUM SOLENOID CONTROL CIRCUIT TO THE PCM CONNECTOR. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR SPEED VACUUM CONTROL

THE OPEN CONTROL SOLENOID CIRCUIT.*

YES

WITH AN OHMMETER, MEASURE THE RESISTANCE OF THE...

SPEED CONTROL VENT SOLENOID CONTROL CIRCUIT TO THE PCM CONNECTOR. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN SPEED CONTROL VENT SOLENOID CONTROL CIRCUIT.*

YES

REPLACE THE SPEED CONTROL SERVO.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
757

S TEST SC-1B CHECKING THE SPEED CONTROL OPERATION P E Perform TEST SC-1A Before Proceeding E D C O N T R O L T E S T S
FIG. 1
AB BODY AN AND XJ BODIES

FIG. 2
BR BODY ZJ BODY

FIG. 3

FIG. 4
758

FIG. 5

TEST SC-1B

CHECKING THE SPEED CONTROL OPERATION

Perform TEST SC-1A Before Proceeding

S P E E D
YES REPAIR THE SWITCHED S/C POWER SUPPLY OUTPUT CICUIT SHORTED TO GROUND.*

START TEST SC-1B.

USING AN OHMMETER, MEASURE THE SWITCHED S/C POWER SUPPLY CKT AT S/C SERVO TO GND. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

C O N T R O L T E S T S

DISCONNECT THE BRAKE SWITCH CONNECTOR.** SEE GENERAL INFO 4.7

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

WITH THE VENT SOLENOID STILL IN ACTUATION MODE.

MEASURE THE S/C BRAKE SWITCH OUTPUT CIRCUIT. FIG. 2, 3, 4 OR 5

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

CONTINUE TEST SC-1B ON THE NEXT PAGE.

YES

KEY OFF, USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE SWITCHED S/C BRAKE SWITCH OUTPUT CIRCUIT FOR RESISTANCE....

FROM BRAKE SWITCH CONNECTOR TO SPEED CONTROL SERVO. FIG. 1 AND 2 THRU 5

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN SWITCHED S/C POWER SUPPLY CIRCUIT.*

YES

REPLACE THE BRAKE SWITCH.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
759

S TEST SC-1B P E E AB BODY D C O N T R O L T E S T S

CONTINUED CHECKING THE SPEED CONTROL OPERATION
AN AND XJ BODIES

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
760

FIG. 4

TEST SC-1B

CONTINUED - CHECKING THE SPEED CONTROL OPERATION

S P E E D C O N T R O L

TEST SC-1B CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE PCM.** SEE GENERAL INFO 4.1

T E S T S

USE AN OHMMETER IN THE FOLLOWING STEP. MEASURE RESISTANCE OF THE SWITCHED...

S/C POWER SUPPLY OUTPUT CKT, PCM TO BRAKE SWITCH. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.O OHMS?

NO

REPAIR THE OPEN S/C POWER SUPPLY CIRCUIT, PCM TO BRAKE SWITCH.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
761

S TEST SC-2A CHECKING THE SPEED CONTROL OPERATION P E Perform TEST SC-1A Before Proceeding E AB, AN, BR AND XJ BODIES 1996 2.5/3.9/4.0/5.2/5.9/8.0L AB/AN/BR/XJ/ZJ Publication No. 81-699-96103 D TSB 26-03-98 March, 1998 C O N T R O L T E S T S
FIG. 1
ZJ BODY AB, AN AND XJ BODIES

FIG. 2
BR BODY ZJ BODY

FIG. 3

FIG. 4
762

FIG. 5

TEST SC-2A

CHECKING THE SPEED CONTROL OPERATION

Perform TEST SC-1A Before Proceeding

S P E E D
YES REPAIR AS NECESSARY.*

START TEST SC-2A.

KEY OFF, DISCONNECT THE SPEED CONTROL SWITCH(S).** SEE GENERAL INFO 4.7

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED?

NO

WITH AN OHMMETER, MEASURE THE SPEED CONTROL SWITCH SIGNAL TO GROUND. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE SPEED CONTROL SWITCH SIGNAL CIRCUIT, FOR A SHORT TO GROUND.*

C O N T R O L T E S T S

NO

WITH AN OHMMETER, MEASURE...

THE SPEED CONTROL SENSOR GROUND CIRCUIT AT THE SWITCH TO GROUND. FIG. 1 OR 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN SENSOR GROUND CIRCUIT TO SWITCH.*

YES

CONNECT A JUMPER ACROSS SIGNAL CKT AND GROUND CKT AT SWITCH CONNECTOR. FIG. 1 OR 2

WITH THE DRB, READ THE SPEED CONTROL SWITCH VOLTAGE.

DOES THE DRB SHOW "0.00V"?

YES

REPLACE THE SPEED CONTROL SWITCH.*

NO

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE S/C SWITCH SIGNAL CKT, SWITCH TO PCM. FIG. 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

DISCONNECT THE CLOCKSPRING 4-WAY TO I/P HARNESS.** SEE GENERAL INFO 4.7

USING AN OHMMETER, MEASURE THE S/C SWITCH SIGNAL CKT CLOCKSPRING TO PCM. FIG. 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE CLOCKSPRING.*

NO

REPAIR THE OPEN SPEED CONTROL SWITCH SIGNAL CIRCUIT.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
763

S TEST SC-3A CHECKING THE SPEED CONTROL OPERATION P E Perform TEST SC-1A Before Proceeding E AB BODY AN AND XJ BODY D C O N T R O L T E S T S

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
764

FIG. 4

TEST SC-3A

CHECKING THE SPEED CONTROL OPERATION

Perform TEST SC-1A Before Proceeding

S P E E D C O N T R O L T E S T S

START TEST SC-3A.

DISCONNECT THE BRAKE SWITCH CONNECTOR.** SEE GENERAL INFO 4.7

KEY ON, WITH A VOLTMETER, MEASURE THE BRAKE SWITCH SENSE CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

CONTINUE TEST SC-3A ON THE NEXT PAGE.

YES

CONNECT A JUMPER BETWEEN THE BRAKE SWITCH SENSE AND GROUND. FIG. 1, 2, 3 OR 4

WITH THE DRB, READ THE BRAKE SWITCH INPUT STATUS.

DOES THE DRB SHOW BRAKE SW "RELEASED"?

YES

REPLACE THE BRAKE SWITCH.*

NO

REPAIR THE OPEN GROUND CIRCUIT.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
765

S TEST SC-3A CONTINUED - CHECKING THE SPEED CONTROL OPERATION P E E AB, AN AND XJ BODIES D C O N T R O L T E S T S
FIG. 1
BR BODY

FIG. 2
ZJ BODY

FIG. 3
766

TEST SC-3A

CONTINUED - CHECKING THE SPEED CONTROL OPERATION

S P E E D C O N T R O L

TEST SC-3A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

IS ANY TERMINAL DAMAGED, PUSHED OUT OR MISWIRED?

YES

REPAIR AS NECESSARY.*

NO

T E S T S

USING AN OHMMETER IN THE FOLLOWING STEPS, MEASURE THE BRAKE SWITCH...

SENSE CIRCUIT AT PCM TO GROUND. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE BRAKE SWITCH SENSE CIRCUIT, SHORTED TO GROUND.*

NO

CONTINUE TEST SC-3A ON THE NEXT PAGE.

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
767

S TEST SC-3A P E E AB BODY D C O N T R O L T E S T S

CONTINUED - CHECKING THE SPEED CONTROL OPERATION
AB AND XJ BODIES

FIG. 1
BR BODY ZJ BODY

FIG. 2

FIG. 3
768

FIG. 4

TEST SC-3A

CONTINUED - CHECKING THE SPEED CONTROL OPERATION

S P E E D C O N T R O L T E S T S

TEST SC-3A CONTINUED FROM THE PREVIOUS PAGE.

MEASURE THE BRAKE SWITCH SENSE CKT FROM PCM TO BRAKE SWITCH CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN BRAKE SWITCH SENSE CIRCUIT.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
769

S TEST SC-4A CHECKING THE SPEED CONTROL OPERATION P E Perform TEST SC-1A Before Proceeding E AB BODY D C O N T R O L T E S T S
FIG. 1
AN BODY BR BODY

FIG. 2
XJ BODY ZJ BODY

FIG. 3

FIG. 4
770

FIG. 5

TEST SC-4A

CHECKING THE SPEED CONTROL OPERATION

Perform TEST SC-1A Before Proceeding

S P E E D C O N T R O L T E S T S

START TEST SC-4A.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

NOTE: THE GEAR SELECTOR SHOULD STILL BE IN DRIVE.

WITH AN OHMMETER, MEASURE THE P/N POSITION SWITCH SENSE CIRCUIT. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

DISCONNECT THE PARK/NEUTRAL SWITCH.** SEE GENERAL INFO 4.7

WITH AN OHMMETER, MEASURE THE P/N POSITION SWITCH SENSE CKT AT PCM. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPLACE THE PARK/NEUTRAL SWITCH.*

YES

REPAIR THE PARK/NEUTRAL POSITION SENSE CIRCUIT, SHORTED TO GROUND.*

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
771

S TEST SC-5A CHECKING THE SPEED CONTROL OPERATION P E Perform TEST SC-1A Before Proceeding E NOTES D C O N T R O L T E S T S

772

TEST SC-5A

CHECKING THE SPEED CONTROL OPERATION

Perform TEST SC-1A Before Proceeding

At this time the speed control switch and servo functions appear to operate properly. Using the DRB, monitor the speed control ‘‘cutout’’ status. Road test the vehicle at speeds over 35 mph and attempt to set the speed control. The following items will not allow the speed control to set. The last or most recent cause for speed control not to set is indicated by the ‘‘Denied’’ status. Denied Message ON/OFF SPEED RPM BRAKE The powertrain control module does not see an ‘‘ON’’ signal from the switch. The vehicle speed as seen by the powertrain control module is not greater than 36 mph. The engine rpm is excessively high. The brake switch sense circuit is open indicating to the powertrain control module that the brakes are applied. The sense circuit is grounded through the brake pedal switch when the brakes are released. The park/neutral switch sense circuit is grounded indicating to the powertrain control module that the transmission is not in gear. The sense circuit is grounded through the park/neutral switch when the transmission is in park or neutral. The PCM senses excessive engine rpm for a given vehicle speed. The powertrain control module senses a servo solenoid circuit trouble code that is maturing or set in memory.

S P E E D C O N T R O L T E S T S

P/N

RPM/SPD SOL FLT

*Perform Verification TEST VER-4A.

**Check connectors - Clean / repair as necessary.
773

C TEST CH-1A CHARGING SYSTEM NO CODE TEST H A Perform DTC TEST Before Proceeding R AB BODY AN AND BR BODIES G I N G T E S T S

ZJ BODY

XJ BODY

FIG. 1
774

TEST CH-1A

CHARGING SYSTEM NO CODE TEST

Perform DTC TEST Before Proceeding

START TEST CH-1A.

BATTERY CONDITION MUST BE VERIFIED PRIOR TO THIS TEST.

C H A R G I N G T E S T S

INSPECT THE GENERATOR BELT TENSION AND CONDITION.

IS THE GENERATOR BELT OK?

NO

REPAIR AS NECESSARY.*

YES

START ENGINE, TURN ON ALL ACCESSORIES AND RAISE THE ENGINE SPEED TO 2000 RPM FOR 30 SECONDS.

RETURN THE ENGINE TO IDLE SPEED AND READ CODES.

ARE THERE ANY CHARGING SYSTEM TROUBLE CODES?

YES

PERFORM DTC TEST.

NO

TURN ENGINE OFF (IGNITION ON).

WITH THE DRB, ACTUATE THE GENERATOR FIELD.

USING A VOLTMETER BACKPROBE THE GENERATOR FIELD...

DRIVER TERMINAL AT THE BACK OF THE GENERATOR. FIG. 1

NOTE: THE VOLTAGE SHOULD CYCLE FROM 0 TO BATTERY VOLTAGE EVERY 1.4 SECONDS.

WHILE MONITORING THE VOLTMETER, WIGGLE THE FIELD TERMINALS BACK TO THE PCM AND ASD RELAY.

WAS THERE ANY INTERRUPTION IN THE NORMAL CYCLE BETWEEN 0 AND BATTERY VOLTAGE? NO

YES

REPAIR THE WIRE WHERE WIGGLING INTERRUPTED THE VOLTAGE CYCLE.*

STOP ACTUATION.

WITH THE DRB, READ TROUBLE CODES.

ARE THERE ANY CHARGING SYSTEM TROUBLE CODES?

YES

PERFORM DTC TEST.

NO

CONTINUE TEST CH-1A ON THE NEXT PAGE.

*Perform Verification TEST VER-3A.

**Check connectors - Clean / repair as necessary.
775

C TEST CH-1A H A R AB BODY G I N G T E S T S

CONTINUED - CHARGING SYSTEM NO CODE TEST
AN AND BR BODIES

ZJ BODY

XJ BODY

FIG. 1
776

TEST CH-1A

CONTINUED - CHARGING SYSTEM NO CODE TEST

TEST CH-1A CONTINUED FROM THE PREVIOUS PAGE.

USE A VOLTMETER IN THE FOLLOWING STEP.

TEST BETWEEN THE GENERATOR (12V) B(+) TERMINAL AND THE BATTERY (+) SIDE. FIG. 1

C H A R G I N G T E S T S

CAUTION: ENSURE ALL WIRES ARE CLEAR OF THE ENGINE’S MOVING PARTS.

START THE ENGINE.

IS THE VOLTAGE ABOVE 0.4 VOLT?

YES

REPAIR THE B(+) CIRCUIT FOR HIGH RESISTANCE BETWEEN THE GENERATOR AND THE BATTERY.*

NO

IGNITION KEY OFF. USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE BETWEEN THE GENERATOR CASE AND BATTERY (-) SIDE.

CAUTION: ENSURE ALL WIRES ARE CLEAR OF THE ENGINE’S MOVING PARTS.

START THE ENGINE.

IS THE VOLTAGE ABOVE 0.1 VOLT?

YES

REPAIR GENERATOR GROUND HIGH RESISTANCE GENERATOR CASE TO BATTERY (-) SIDE.*

NO

WITH THE DRB, READ THE BATTERY VOLTAGE AND RECORD.

USING A VOLTMETER, READ BATTERY VOLTAGE B(+) TO B(-) TERMINAL.

RECORD SECOND VOLTAGE READING. COMPARE THE TWO VOLTAGE READINGS.

IS THE VOLTAGE DIFFERENCE LESS THAN ONE VOLT?

YES TEST COMPLETE.*

NO

CONTINUE TEST CH-1A ON THE NEXT PAGE.

*Perform Verification TEST VER-3A.

**Check connectors - Clean / repair as necessary.
777

C TEST CH-1A H A R G I N G T E S T S

CONTINUED - CHARGING SYSTEM NO CODE TEST

FIG. 1

778

TEST CH-1A

CONTINUED - CHARGING SYSTEM NO CODE TEST

C H A R G I N G T E S T S

TEST CH-1A CONTINUED FROM THE PREVIOUS PAGE.

TURN IGNITION OFF.

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

TURN IGNITION ON, USING A VOLTMETER, MEASURE THE FUSED B(+) AT THE PCM. FIG. 1

IS THE VOLTAGE WITHIN ONE VOLT OF THE DRB RECORDED READING?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE B(+) CIRCUIT FOR HIGH RESISTANCE BETWEEN THE PCM FUSED B(+) AND THE BATTERY.*

*Perform Verification TEST VER-3A.

**Check connectors - Clean / repair as necessary.
779

N TEST NS-SEL O S T A R T T E S T S
CONDITION

NO START SELECTION MENU

Perform DTC TEST Before Proceeding

TEST

Engine will not crank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NS-9 Engine starts and the DRB displays ‘‘No Response’’ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NS-6B Engine does not start and the DRB displays ‘‘No Response’’ . . . . . . . . . . . . . . . . . . . . . . . . .NS-6A All gasoline engine except 8.0L no-start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NS-1 Compressed natural gas no-start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NS-11 8.0L engine no-start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NS-10 Diesel engine no-start only when engine temp is 40°F or below . . . . . . . . . . . . . . . . . . . . . . .NS-14 Diesel engine no-start independent of temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NS-15

780

TEST NS-SEL NO START SELECTION MENU
Perform DTC TEST Before Proceeding

N O S T A R T T E S T S

NOTES

781

N TEST NS-1A O S T A R T T E S T S

QUALIFYING A NO START CONDITION

Perform TEST NS-SEL Before Proceeding

FIG. 1

782

TEST NS-1A

QUALIFYING A NO START CONDITION

Perform TEST NS-SEL Before Proceeding

N O S T A R T T E S T S

START TEST NS-1A.

KEY OFF. DISCONNECT THE SPARK PLUG CABLE AT SPARK PLUG #1. SEE GENERAL INFO 4.2

CONNECT THE CABLE TO A SPARK TESTER.

CONNECT THE SPARK TESTER TO A GOOD GROUND. FIG. 1

WHILE CRANKING THE ENGINE FOR 10 SECONDS, WATCH FOR SPARK.

NO

IS THERE GOOD SPARK?

YES

DOES THE VEHICLE START AND STALL?

YES

PERFORM TEST NS-7A.

NO

TURN IGNITION OFF.

REMOVE THE COIL SECONDARY CABLE FROM THE DISTRIBUTOR.

PERFORM TEST NS-2A.

CONNECT THE CABLE TO A SPARK TESTER. FIG. 1

CONNECT THE SPARK TESTER TO A GOOD GROUND. FIG. 1

WHILE CRANKING THE ENGINE FOR 10 SECONDS, WATCH FOR SPARK.

CONTINUE TEST NS-1A ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
783

N TEST NS-1A O S T A R T T E S T S

CONTINUED - QUALIFYING A NO START CONDITION

FIG. 1

FIG. 2
784

TEST NS-1A

CONTINUED - QUALIFYING A NO START CONDITION

N O S T A R T T E S T S

TEST NS-1A CONTINUED FROM THE PREVIOUS PAGE.

IS THERE GOOD SPARK?

YES

REPAIR THE SECONDARY IGNITION: DISTRIBUTOR CAP, ROTOR, CABLES.*

NO

TURN IGNITION OFF.

REMOVE THE COIL SECONDARY CABLE.

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE RESISTANCE OF THE COIL SECONDARY CABLE. FIG. 1

IS THE RESISTANCE ABOVE 15K OHMS?

YES

REPLACE THE COIL SECONDARY CABLE.*

NO

REMOVE THE DISTRIBUTOR CAP. FIG. 2

WHILE CRANKING THE ENGINE, WATCH FOR THE ROTOR TO TURN.

DID THE ROTOR TURN WHEN THE ENGINE WAS CRANKED?

NO

REPAIR THE DISTRIBUTOR DRIVE SYSTEM.*

YES

REINSTALL THE DISTRIBUTOR CAP AND IGNITION COIL CABLE.

DISCONNECT THE IGNITION COIL CONNECTOR.**

IS ANY TERMINAL DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR TERMINAL(S) FOR DAMAGE, PUSHOUT, OR MISWIRING.*

NO

TURN IGNITION ON.

WITH THE DRB, ACTUATE THE GENERATOR FIELD.

WITH GENERATOR FIELD STILL ACTUATING, USE A VOLTMETER IN THE NEXT STEP.

CONTINUE TEST NS-1A ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
785

N TEST NS-1A O S T A R T T E S T S

CONTINUED - QUALIFYING A NO START CONDITION

AB, AN AND XJ BODIES

FIG. 1
BR BODY

FIG. 2
ZJ BODY

FIG. 3
786

TEST NS-1A

CONTINUED - QUALIFYING A NO START CONDITION

N O S T A R T T E S T S

TEST NS-1A CONTINUED FROM THE PREVIOUS PAGE.

MEASURE THE ASD RELAY OUTPUT CIRCUI IN THE COIL CONNECTOR. FIG. 1, 2, OR 3

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CKT FROM COIL CONNECTOR TO SPLICE.*

YES

CONTINUE TEST NS-1A ON THE NEXT PAGE

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
787

N TEST NS-1A O S T A R T T E S T S

CONTINUED - QUALIFYING A NO START CONDITION

FIG. 1

FIG. 2
788

TEST NS-1A

CONTINUED - QUALIFYING A NO START CONDITION

N O S T A R T T E S T S

TURN IGNITION OFF. TEST NS-1A CONTINUED FROM PREVIOUS PAGE USE AN OHMMETER IN THE FOLLOWING STEPS.

MEASURE THE RESISTANCE BETWEEN THE PRIMARY TERMINALS OF THE IGNITION COIL.FIG. 1

IS THE PRIMARY RESISTANCE BETWEEN 0.60 AND 1.40 OHMS?

NO

REPLACE THE IGNITION COIL.*

YES

MEASURE THE RESISTANCE BETWEEN THE PRIMARY AND SECONDARY TERMINALS OF THE COIL. FIG. 2

IS THE SECONDARY RESISTANCE BETWEEN 11,300 - 15,300 OHMS?

NO

REPLACE THE IGNITION COIL.*

YES

CONTINUE TEST NS-1A ON THE NEXT PAGE

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
789

N TEST NS-1A O S T A R T T E S T S

CONTINUED - QUALIFYING A NO START CONDITION

AB, AN AND XJ BODIES

FIG. 1
BR BODY

FIG. 2
ZJ BODY

FIG. 3
790

TEST NS-1A

CONTINUED - QUALIFYING A NO START CONDITION

N O S T A R T T E S T S

TEST NS-1A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE POWERTRAIN CONTROL MODULE BLACK CONNECTOR.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE THE IGNITION COIL DRIVER CKT AT THE PCM...

FOR RESISTANCE TO GROUND. FIG. 1, 2, OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IGNITION COIL DRIVER CIRCUIT FOR SHORT TO GROUND.*

NO

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE COIL DRIVER CIRCUIT...

FROM THE IGNITION COIL TO THE PCM CONNECTOR. FIG. 1, 2, OR 3

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR OPEN IGNITION COIL DRIVER FROM PCM TO COIL CONNECTOR.*

NO

CHECK VALVE TIMING PER SERVICE MANUAL INSTRUCTIONS.

IS VALVE TIMING WITHIN SPECIFICATIONS?

NO

REPAIR THE ENGINE VALVE TIMING AS NECESSARY.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
791

N TEST NS-2A O S T A R T T E S T S

CHECKING FUEL SYSTEM

Perform TEST NS-SEL Before Proceeding

START TEST NS-2A.

ENSURE THE THROTTLE CABLE IS NOT HOLDING THE THROTTLE OPEN. SEE GENERAL INFO 4.0

IS THE THROTTLE BEING HELD OPEN BY THE CABLE?

YES

REPAIR THE CONDITION THAT IS HOLDING THE THROTTLE BODIES OPEN.*

NO

WITH THE DRB, GO INTO THEFT ALARM AND SELECT MONITORED DISPLAY.

DOES THE DRB SHOW "ENGINE CONTROLLER OK TO RUN ENGINE"?

YES

CONTINUE TEST NS-2A ON THE NEXT PAGE.

NO

PERFORM THE THEFT ALARM TEST IN THE BODY DIAGNOSTIC PROCEDURES MANUAL.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
792

TEST NS-2A

CONTINUED - CHECKING FUEL SYSTEM

Perform TEST NS-SEL Before Proceeding

N O S T A R T T E S T S

TEST NS-2A CONTINUED FROM THE PREVIOUS PAGE.

WITH THE DRB, ACTUATE THE FUEL SYSTEM.

NOTE: IT MAY BE NECESSARY TO USE A MECHANICS STETHOSCOPE IN THE NEXT STEP.

LISTEN FOR FUEL PUMP OPERATION AT THE FUEL TANK.

CAN THE FUEL PUMP OPERTION BE HEARD?

NO

PERFORM TEST NS-5A.

YES

WARNING: THE FUEL SYSTEM MUST BE OPENED AND MAY BE UNDER HIGH PRESSURE. SEE GENERAL INFO 9.0

KEY OFF. INSTALL A FUEL PRESSURE GAUGE TO FUEL SYSTEM.

NOTE: THE FUEL TANK MUST BE AT LEAST 1/4 FULL FOR THE FOLLOWING TESTS.

TURN IGNITION ON. WITH THE DRB, ACTUATE THE FUEL SYSTEM. READ THE FUEL PRESSURE GAUGE. IS THE FUEL PRESSURE ABOVE 54.2 PSI? YES

REPLACE THE FUEL FILTER/REGULATOR AND PRIMARY FILTER.*

NO

IS THE FUEL PRESSURE BELOW 44.2 PSI?

YES

PERFORM TEST NS-4A.

NO

DID THE VEHICLE INITIALLY START & STALL REPEATEDLY?

YES

PERFORM TEST NS-7A.

NO

PERFORM TEST NS-3A.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
793

N TEST NS-3A O S T A R T T E S T S
8.0L

CHECKING THE MECHANICAL SYSTEM

FIG. 1
AB, AN AND BR 3.9L AB, AN, BR AND ZJ 5.2L AND 5.9L

FIG. 2
XJ 2.5L XJ AND ZJ 4.0L

FIG. 3

FIG. 4
794

FIG. 5

TEST NS-3A

CHECKING THE MECHANICAL SYSTEM

N O S T A R T T E S T S

START TEST NS-3A.

REMOVE ALL SPARK PLUGS & INSPECT THE TIPS FOR WET FUEL.

ARE THE SPARK PLUG TIPS WET?

YES

CLEAN THE SPARK PLUGS.

NO

REINSTALL THE SPARK PLUGS.

INSPECT SPARK PLUG CABLES FOR CORRECT PLACEMENT. FIG. 1, 2, 3, 4 OR 5

ARE ALL SPARK PLUG CABLES POSITIONED CORRECTLY? YES

NO

REINSTALL SPARK PLUG CABLES AS NECESSARY.*

TURN IGNITION OFF.

USING SERVICE MANUAL PROCEDURES, CHECK VALVE TIMING.

IS VALVE TIMING WITHIN SPECIFICATIONS?

NO

REPAIR THE ENGINE VALVE TIMING AS NECESSARY.*

YES

CHECK EXHAUST SYSTEM FOR ANY RESTRICTIONS.

IS THE EXHAUST FREE OF RESTRICTIONS?

NO

REPAIR AS NECESSARY.*

YES

USING SERVICE MANUAL PROCEDURES, CHECK ENGINE COMPRESSION.

IS ENGINE COMPRESSION WITHIN SPECIFICATIONS?

NO

REPAIR AS NECESSARY.*

YES

REPLACE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
795

N TEST NS-4A O S T A R T T E S T S

REPAIRING LOW FUEL PRESSURE

Perform TEST NS-SEL Before Proceeding

NOTES

796

TEST NS-4A

REPAIRING LOW FUEL PRESSURE

Perform TEST NS-SEL Before Proceeding

N O S T A R T T E S T S

START TEST NS-4A.

INSPECT FUEL LINES FROM TANK TO FUEL RAIL FOR RESTRICTION. SEE GENERAL INFO 4.0

IS THERE ANY RESTRICTION?

YES

REPAIR RESTRICTED FUEL LINES.*

NO

REPLACE THE FUEL PUMP MODULE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
797

N TEST NS-5A O S T A R T T E S T S
AB BODY

CHECKING THE FUEL PUMP
AN BODY

Perform TEST NS-2A Before Proceeding

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
798

TEST NS-5A

CHECKING THE FUEL PUMP

Perform TEST NS-2A Before Proceeding

N O S T A R T T E S T S
DOES THE FUEL PUMP RELAY PULSATE WITH ACTUATION? NO PERFORM TEST TC-101A.

START TEST NS-5A.

WITH THE DRB, STOP THE ACTUATION TEST.

WITH THE DRB, ACTUATE THE FUEL PUMP RELAY.

TOUCH THE FUEL PUMP RELAY. FIG. 1, 2, 3, 4 OR 5

YES

DISCONNECT THE FUEL PUMP RELAY.** IGNITION KEY OFF. FIG. 1, 2, 3, 4 OR 5

USING A VOLTMETER, MEASURE THE FUEL PUMP RLY FUSED B(+) CIRCUIT. FIG. 1, 2, 3, 4 OR 5

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE FUEL PUMP RELAY B(+) CIRCUIT FOR AN OPEN TO SPLICE.*

YES

CONTINUE TEST NS-5A ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
799

N TEST NS-5A O S T A R T T E S T S
AB BODY

CONTINUED - CHECKING THE FUEL PUMP
AN BODY

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
800

TEST NS-5A

CONTINUED - CHECKING THE FUEL PUMP

N O S T A R T T E S T S

TEST NS-5A CONTINUED FROM THE PREVIOUS PAGE.

INSTALL A SUBSTITUTE RELAY OF THE SAME PART NUMBER FOR THE FUEL PUMP RELAY.

ATTEMPT TO START THE ENGINE

DOES THE ENGINE START?

YES

REPLACE THE FUEL PUMP RELAY.*

NO

REINSTALL THE ORIGINAL FUEL PUMP RELAY.

DISCONNECT THE FUEL PUMP HARNESS CONNECTOR.** SEE GENERAL INFO 4.5

CAUTION: IT IS CRITICAL THAT THE FUEL PUMP CONNECTOR HAS A CLEAN AND TIGHT CONNECTION.**

IGNITION ON. WITH THE DRB, ACTUATE THE FUEL SYSTEM.

USING A VOLTMETER, MEASURE THE FUEL PUMP RLY OUTPUT CIRCUIT. FIG. 1, 2, 3, 4 OR 5

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUEL PUMP RELAY OUTPUT CIRCUIT.*

YES

WITH THE DRB, STOP THE ACTUATION TEST.

USING AN OHMMETER, MEASURE THE FUEL PUMP GROUND CKT IN THE FUEL PUMP CONN. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN FUEL PUMP GROUND CIRCUIT.*

YES

REPLACE THE FUEL PUMP.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
801

N TEST NS-6A O S T A R T T E S T S

REPAIRING A ؆NO RESPONSE؆ CONDITION
AN BODY

Perform DTC TEST OR NS-SEL Before Proceeding
AB AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
802

FIG. 4

TEST NS-6A

REPAIRING A ؆NO RESPONSE؆ CONDITION

Perform DTC TEST OR NS-SEL Before Proceeding

N O S T A R T T E S T S

START TEST NS-6A.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE BLACK CONNECTOR.** SEE GENERAL INFO 4.1

USING AN OHMMETER, MEASURE BOTH GROUND CIRCUITS AT PCM CONNECTOR. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS AT BOTH TERMINALS?

NO

REPAIR THE OPEN GROUND(S) AT THE POWERTRAIN CONTROL MODULE.*

YES

TURN IGNITION ON.

USING A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CIRCUIT. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGN SWITCH OUTPUT CIRCUIT BETWEEN PCM & IGNITION SWITCH.*

YES

CONTINUE TEST NS-6A ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
803

N TEST NS-6A O S T A R T T E S T S
AB BODY

CONTINUED - REPAIRING A ؆NO RESPONSE؆ CONDITION
AN BODY

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
804

TEST NS-6A

CONTINUED - REPAIRING A ؆NO RESPONSE؆ CONDITION

N O S T A R T T E S T S

TEST NS-6A CONTINUED FROM THE PREVIOUS PAGE.

MEASURE THE FUSED B(+) CKT IN THE PCM CONNECTOR. SEE FIG. 1, 2, 3 OR 4 ON PREVIOUS PAGE

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

PERFORM TEST NS-6D.

NO

REMOVE THE FUSE IN THE PDC THAT SUPPLIES FUSED B(+) TO PCM CAVITY A22. FIG. 1, 2, 3, 4 OR 5

NO INSPECT THE FUSE. IS THE FUSE OK?

CONTINUE TEST NS-6A ON THE NEXT PAGE.

YES

USING A VOLTMETER, MEASURE THE B(+) SIDE OF THE FUSE SOCKET. FIG. 1, 2, 3, 4 OR 5

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN B(+) CIRCUIT FROM FUSE TO THE BATTERY .*

YES

REPAIR THE OPEN FUSED B(+) CIRCUIT FROM FUSE TO PCM.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
805

N TEST NS-6A O S T A R T T E S T S

CONTINUED - REPAIRING A ؆NO RESPONSE؆ CONDITION
AN BODY

AB AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
806

FIG. 4

TEST NS-6A

CONTINUED - REPAIRING A ؆NO RESPONSE؆ CONDITION

N O S T A R T T E S T S

TEST NS-6A CONTINUED FROM THE PREVIOUS PAGE.

TURN IGNITION OFF. DISCONNECT THE AUTO SHUTDOWN RELAY.** SEE GENERAL INFO 4.6

NOTE: THE PREVIOUSLY INSPECTED FUSE SHOULD STILL BE REMOVED.

WITH AN OHMMETER, MEASURE THE FUSED B(+) CIRCUIT IN PCM CONNECTOR TO GND. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE FUSED B(+) CIRCUIT FOR A SHORT TO GROUND. REPLACE FUSE.*

NO

MEASURE THE ASD RELAY OUTPUT CKT IN THE ASD RELAY CONNECTOR...

FIG. 1, 2, 3, 4 OR 5 ON FOLLOWING PAGE.

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

CONTINUE TEST NS-6A ON THE NEXT PAGE.

NO

IS THE VEHICLE EQUIPPED WITH A DIESEL ENGINE?

NO

PERFORM TEST NS-6C.

YES

NOTE: AN INTERMITTENT ASD RELAY OUTPUT CKT SHORT TO GROUND MAY EXIST.

REPLACE FUSE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
807

N TEST NS-6A O S T A R T T E S T S
AB BODY

CONTINUED - REPAIRING A ؆NO RESPONSE؆ CONDITION
AN BODY

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
808

TEST NS-6A

CONTINUED - REPAIRING A ؆NO RESPONSE؆ CONDITION

N O S T A R T T E S T S

TEST NS-6A CONTINUED FROM THE PREVIOUS PAGE.

IS THE VEHICLE EQUIPPED WITH A DIESEL ENGINE?

YES

CONTINUE TEST NS-6A ON THE NEXT PAGE.

NO

DISCONNECT THE CONNECTORS FOR EACH OXYGEN SENSOR.** SEE GENERAL INFO 4.4

WITH AN OHMMETER, MEASURE THE ASD RLY OUTPUT CIRCUIT FOR RESISTANCE TO GND. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE ABOVE 5.0 OHMS?

MEASURE THE ASD YES RELAY OUTPUT CKT IN EACH O2 SENSOR FOR RESISTANCE TO GND. SEE GENERAL INFO 4.4

NO

NOTE: THE OXYGEN SENSORS MUST REMAIN DISCONNECTED FOR THE REMAINDER OF THE TEST.

REPLACE THE OXYGEN SENSOR THAT HAS CONTINUITY TO GROUND. REPLACE FUSE.*

DISCONNECT THE IGNITION COIL CONNECTOR.** SEE GENERAL INFO 4.2

WITH AN OHMMETER, MEASURE THE ASD RLY OUTPUT CIRCUIT FOR RESISTANCE TO GND. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPLACE THE IGNITION COIL. REPLACE FUSE.*

NO

DISCONNECT THE GENERATOR FIELD CONNECTOR.** SEE GENERAL INFO 4.2

WITH AN OHMMETER, MEASURE THE ASD RLY OUTPUT CIRCUIT FOR RESISTANCE TO GND. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR GENERATOR FOR SHORT TO GROUND. REPLACE FUSE.*

NO

CONTINUE TO MONITOR OHMMETER DISPLAY WHILE DISCONNECTING EACH FUEL INJECTOR. SEE GENERAL INFO 4.2

IS THE RESISTANCE ABOVE 5.0 OHMS WHEN ANY OF THE INJECTORS ARE DISCONNECTED? NO

YES

REPLACE THE FUEL INJECTOR THAT CAUSED A CHANGE IN RESISTANCE. REPLACE FUSE.*

REPAIR ASD RELAY OUTPUT CIRCUIT FOR HARNESS SHORT TO GROUND. REPLACE FUSE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
809

N TEST NS-6B O S T A R T T E S T S
AB BODY

REPAIRING A ؆NO RESPONSE؆ CONDITION
AN BODY

Perform DTC TEST OR NS SEL Before Proceeding

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
810

TEST NS-6B

REPAIRING A ؆NO RESPONSE؆ CONDITION
1996 Powertrain 2.5L/3.9L/4.0L/5.2L/5.9L/8.0L SFI/MPI/CNG/DIESEL AB/AN/BR/XJ/ZJ Publication No. 81-699-96103 TSB 26-10-99 October, 1999

Perform DTC TEST OR NS SEL Before Proceeding

N O S T A R T T E S T S

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
811

N TEST NS-6B O S T A R T T E S T S
AB BODY

CONTINUED - REPAIRING A ؆NO RESPONSE؆ CONDITION
AN BODY

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
812

TEST NS-6B

CONTINUED - REPAIRING A ؆NO RESPONSE؆ CONDITION

N O S T A R T T E S T S

TEST NS-6B CONTINUED FROM THE PREVIOUS PAGE.

MEASURE THE RESISTANCE OF THE SCI RECEIVE CKT FROM THE PCM TO THE DLC. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN SCI RECEIVE CIRCUIT.*

YES

CONNECT THE DRB TO A FUNCTIONAL DATA LINK ON ANOTHER VEHICLE.

TURN IGNITION ON.

WITH THE DRB, ATTEMPT TO READ TROUBLE CODES.

DID THE DRB DISPLAY "NO RESPONSE"?

NO

REPLACE THE INITIAL VEHICLE’S POWERTRAIN CONTROL MODULE.*

YES

SUBSTITUTE ANOTHER DRB ADAPTER CABLE.

WITH THE DRB, ATTEMPT TO READ TROUBLE CODES.

DID THE DRB DISPLAY "NO RESPONSE"?

NO

REPLACE THE DRB ADAPTER CABLE.

YES

HAVE THE DRB REPAIRED OR REPLACED.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
813

N TEST NS-6C O S T A R T T E S T S
AB BODY

REPAIRING A ؆NO RESPONSE؆ CONDITION
AN BODY

Perform TEST NS-6A Before Proceeding

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
814

TEST NS-6C

REPAIRING A ؆NO RESPONSE؆ CONDITION

Perform TEST NS-6A Before Proceeding

N O S T A R T T E S T S

START TEST NS-6C.

IS THE VEHICLE EQUIPPED WITH A CNG FUEL SYSTEM?

YES

CONTINUE NS-6C ON THE NEXT PAGE.

NO

DISCONNECT THE FUEL PUMP ELECTRICAL CONNECTOR.** SEE GENERAL INFO 4.5

WITH AN OHMMETER, MEASURE THE FUEL PUMP RLY OUTPUT CKT IN THE RELAY CONN. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE FUEL PUMP RELAY OUTPUT CIRCUIT FOR A SHORT TO GROUND. REPLACE FUSE.*

NO

NOTE: AN INTERMITTENT FUEL PUMP RELAY OUTPUT CIRCUIT SHORT TO GROUND MAY EXIST.

REPLACE THE FUEL PUMP. REPLACE FUSE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
815

N TEST NS-6C O S T A R T T E S T S
AB BODY

CONTINUED REPAIRING A ؆NO RESPONSE؆ CONDITION

Perform TEST NS-6A Before Proceeding

FIG. 1
AN BODY

FIG. 2
BR BODY

FIG. 3
816

TEST NS-6C

CONTINUED REPAIRING A ؆NO RESPONSE؆ CONDITION

Perform TEST NS-6A Before Proceeding

N O S T A R T T E S T S

TEST NS-6C CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE HIGH PRESSURE SHUT-OFF SOLENOID CONNECTOR.** SEE GENERAL INFO 4.5

USING AN OHMMETER, MEASURE THE FUEL SYSTEM RELAY OUTPUT CKT IN THE RELAY CONN. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE FUEL SYSTEM RELAY OUTPUT CIRCUIT FOR A SHORT TO GROUND. REPLACE FUSE.*

NO

REPLACE THE HIGH PRESSURE FUEL SHUT-OFF SOLENOID. REPLACE FUSE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
817

N TEST NS-6D O S T A R T T E S T S

CHECKING A ؆NO RESPONSE؆ CONDITION

Perform TEST NS-6A Before Proceeding
1996 2.5/3.9/4.0/5.2/5.9/8.0L AB/AN/BR/XJ/ZJ Publication No. 81-699-96103 TSB 26-03-98 March, 1998

FIG. 1
AB, AN AND BR BODIES BR DIESEL

FIG. 2
XJ BODY ZJ BODY

FIG. 3

FIG. 4
818

FIG. 5

TEST NS-6D

CHECKING A ؆NO RESPONSE؆ CONDITION
1996 2.5/3.9/4.0/5.2/5.9/8.0L AB/AN/BR/XJ/ZJ Publication No. 81-699-96103 TSB 26-03-98 March, 1998

Perform TEST NS-6A Before Proceeding

N O S T A R T T E S T S

START TEST NS-6D.

RECONNECT ALL DISCONNECTED CONNECTORS. SEE GENERAL INFO 4.0

USE A VOLTMETER IN THE FOLLOWING STEPS.

NOTE: IF THE VEHICLE IS A BR DIESEL, EQUIPPED WITH A MANUAL TRANS,...

BACKPROBE THE CKP SENSOR 5-VOLT SUPPLY AND SKIP THE TPS DISCONNECT STEP. FIG. 1

ALL OTHER VEH’S, BACKPROBE THE TP SENSOR 5-VOLT SUPPLY CIRCUIT. FIG. 2, 3, 4 OR 5

IGNITION KEY ON. RECORD VOLTMETER READING. IS THE VOLTAGE BELOW 4.0 VOLTS? NO PERFORM TEST NS-6E.

YES

DISCONNECT THE TP SENSOR CONNECTOR.** CONNECT A VOLTMETER TO THE...

TP SENSOR 5-VOLT SUPPLY CIRCUIT AND READ VOLTMETER. FIG. 2, 3, 4 OR 5

IS THE VOLTAGE BELOW 4.0 VOLTS?

NO

REPLACE THE THROTTLE POSITION SENSOR.*

YES

DISCONNECT THE CRANKSHAFT SENSOR.** READ VOLTMETER. SEE GENERAL INFO 4.0

IS THE VOLTAGE BELOW 4.0 VOLTS?

NO

REPLACE THE CRANKSHAFT SENSOR.*

YES

CONTINUE TEST NS-6D ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
819

N TEST NS-6D O S T A R T T E S T S

CONTINUED CHECKING A ؆NO RESPONSE؆ CONDITION

Perform TEST NS-6A Before Proceeding

820

TEST NS-6D

CONTINUED CHECKING A ؆NO RESPONSE؆ CONDITION

Perform TEST NS-6A Before Proceeding

N O S T A R T

TEST NS-6D CONTINUED FROM THE PREVIOUS PAGE.

DOES THE VEHICLE HAVE A DIESEL ENGINE?

YES

CONTINUE TEST NS-6D ON THE NEXT PAGE.

T E S T S

NO

DISCONNECT THE CAMSHAFT SENSOR.** READ VOLTMETER. SEE GENERAL INFO 4.0

IS THE VOLTAGE BELOW 4.0 VOLTS?

NO

REPLACE THE CAMSHAFT SENSOR.*

YES

DISCONNECT THE MAP SENSOR.** READ VOLTMETER. SEE GENERAL INFO 4.0

IS THE VOLTAGE BELOW 4.0 VOLTS?

NO

REPLACE THE MAP SENSOR.*

YES

CONTINUE TEST NS-6D ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
821

N TEST NS-6D O S T A R T T E S T S

CONTINUED CHECKING A ؆NO RESPONSE؆ CONDITION

Perform TEST NS-6A Before Proceeding

FIG. 1
822

TEST NS-6D

CONTINUED CHECKING A ؆NO RESPONSE؆ CONDITION

Perform TEST NS-6A Before Proceeding

N O S T A R T T E S T S

TEST NS-6D CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE VEHICLE SPEED SENSOR.** READ THE VOLTMETER. SEE GENERAL INFO 4.4

IS THE VOLTAGE BELOW 4.0 VOLTS?

NO

REPLACE THE VEHICLE SPEED SENSOR.*

YES

DISCONNECT THE TRANSMISSION SOLENOID CONNECTOR IF EQUIPPED.** SEE GENERAL INFO 4.0

READ VOLTMETER.

IS THE VOLTAGE BELOW 4.0 VOLTS?

NO

REPLACE THE GOVERNOR/TEMP PRESSURE SENSOR.*

YES

DISCONNECT THE VOLTMETER.

MEASURE THE VOLTAGE OF THE SENSOR GROUND CIRCUIT.

IS THE VOLTAGE ABOVE 1.0 VOLT?

YES

REPAIR THE SENSOR GROUND CIRCUIT SHORTED TO VOLTAGE.*

NO

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.1

DISCONNECT THE VOLTMETER.

WITH AN OHMMETER, MEASURE THE RESISTANCE OF THE 5-VOLT PRIMARY SUPPLY CIRCUIT...

TO GROUND AT THE POWERTRAIN CONTROL MODULE CONNECTOR. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE SHORTED 5-VOLT PRIMARY SUPPLY SHORTED TO GROUND.*

NO

MEASURE THE RESISTANCE OF THE 5-VOLT SECONDARY SUPPLY CIRCUIT...

TO GROUND AT THE POWERTRAIN CONTROL MODULE. FIG. 1

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE SHORTED 5-VOLT SECONDARY SUPPLY SHORTED TO GROUND.*

NO

PERFORM TEST NS-6B.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
823

N TEST NS-6E O S T A R T T E S T S

CHECKING A ؆NO RESPONSE؆ CONDITION

Perform TEST NS-6A Before Proceeding

AB, AN AND BR BODIES

BR DIESEL

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
824

FIG. 4

TEST NS-6E

CHECKING A ؆NO RESPONSE؆ CONDITION

Perform TEST NS-6A Before Proceeding

N O S T A R T T E S T S

START TEST NS-6E.

DISCONNECT THE TP SENSOR CONNECTOR.** CONNECT A VOLTMETER TO THE...

TP SENSOR 5 VOLT SUPPLY CIRCUIT AND READ VOLTMETER. FIG. 1, 2, 3 OR 4

IS THE VOLTAGE ABOVE 5.5 VOLTS?

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

YES

REPAIR THE 5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
825

N TEST NS-7A O S T A R T T E S T S
AB BODY

CHECKING IDLE AIR CONTROL MOTOR
AN AND BR BODIES

Perform TEST NS-2A Before Proceeding

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
826

FIG. 4

TEST NS-7A

CHECKING IDLE AIR CONTROL MOTOR

Perform TEST NS-2A Before Proceeding

N O S T A R T T E S T S

START TEST NS-7A.

HOLD THE ENGINE THROTTLE 1/4 OF THE WAY DOWN AND ATTEMPT TO START ENGINE.

DOES THE ENGINE START AND STAY RUNNING AND THEN STALL WHEN THROTTLE IS RELEASED? YES

NO

PERFORM TEST NS-8A.

DISCONNECT THE IDLE AIR CONTROL MOTOR CONNECTOR.** SEE GENERAL INFO 4.0

WITH THE DRB, ACTUATE THE IDLE AIR CONTROL MOTOR.

USE A VOLTMETER IN THE FOLLOWING STEP.

MEASURE THE IDLE AIR CONTROL #3 DRIVER CKT. FIG. 1, 2, 3 OR 4

DID THE VOLTAGE STAY BELOW 1.0 VOLT?

YES

PERFORM TEST NS-7B.

NO

MEASURE THE IDLE AIR CONTROL #1 DRIVER CKT. FIG. 1, 2, 3 OR 4

DID THE VOLTAGE STAY BELOW 1.0 VOLT?

YES

PERFORM TEST NS-7C.

NO

MEASURE THE IDLE AIR CONTROL #4 DRIVER CKT. FIG. 1, 2, 3 OR 4

DID THE VOLTAGE STAY BELOW 1.0 VOLT?

YES

PERFORM TEST NS-7D.

NO

MEASURE THE IDLE AIR CONTROL #2 DRIVER CKT. FIG. 1, 2, 3 OR 4

DID THE VOLTAGE STAY BELOW 1.0 VOLT?

YES

PERFORM TEST NS-7E.

NO

CONTINUE TEST NS-7A ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
827

N TEST NS-7A O S T A R T T E S T S

CONTINUED CHECKING IDLE AIR CONTROL MOTOR

FIG. 1

828

TEST NS-7A

CONTINUED CHECKING IDLE AIR CONTROL MOTOR

N O S T A R T

TEST NS-7A CONTINUED FROM THE PREVIOUS PAGE.

TURN IGNITION OFF.

T E S T S
RECONNECT IDLE AIR CONTROL MOTOR ELECTRICAL CONNECTOR.

REMOVE THE IDLE AIR CONTROL MOTOR FROM THE THROTTLE BODY. SEE GENERAL INFO 4.0

WITH THE DRB, ACTUATE THE IDLE AIR CONTROL MOTOR. FIG. 1

IS THE IDLE AIR CONTROL MOTOR TIP MOVING IN AND OUT?

NO

CONTINUE TEST NS-7A ON THE NEXT PAGE.

YES

INSPECT THROTTLE BODY FOR A RESTRICTION OR CARBON BUILD UP.

IS THE THROTTLE BODY FREE OF RESTRICTIONS?

NO

CLEAN OR REPLACE THROTTLE BODY.*

YES

PERFORM TEST NS-8A.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
829

N TEST NS-7A O S T A R T T E S T S
AB BODY

CONTINUED - CHECKING IDLE AIR CONTROL MOTOR
AN AND BR BODIES

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
830

FIG. 4

TEST NS-7A

CONTINUED - CHECKING IDLE AIR CONTROL MOTOR

N O S T A R T T E S T S

TEST NS-7A CONTINUED FROM THE PREVIOUS PAGE.

KEY OFF, DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

THE FOLLOWING STEPS ARE CHECKING FOR A SHORT BETWEEN THE DRIVER CIRCUITS.

USING AN OHMMETER, MEASURE THE RESISTANCE BETWEEN THE ...

IAC #1 DRIVER AND #2, #3, #4 DRIVERS. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS ON ANY OF THE DRIVERS?

YES

REPAIR THE IAC DRIVER CIRCUITS, SHORTED TOGETHER.*

NO

MEASURE THE RESISTANCE BETWEEN THE ...

IAC #2 DRIVER AND #3, #4 DRIVERS. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS ON ANY OF THE DRIVERS?

YES

REPAIR THE IAC DRIVER CIRCUITS, SHORTED TOGETHER.*

NO

MEASURE THE RESISTANCE BETWEEN THE ...

IAC #3 DRIVER AND #4 DRIVER. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPAIR THE IAC DRIVER CIRCUITS, SHORTED TOGETHER.*

NO

REPLACE THE IDLE AIR CONTROL MOTOR.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
831

N TEST NS-7B O S T A R T T E S T S
AB BODY

CHECKING IDLE AIR CONTROL MOTOR
AN AND BR BODIES

Perform TEST NS-7A Before Proceeding

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
832

FIG. 4

TEST NS-7B

CHECKING IDLE AIR CONTROL MOTOR

Perform TEST NS-7A Before Proceeding

N O S T A R T T E S T S

START TEST NS-7B.

KEY OFF. DISCONNECT POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

IS ANY TERMINAL DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR TERMINAL(S) FOR DAMAGE, PUSHOUT, OR MISWIRING.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

TEST THE IDLE AIR CONTROL MOTOR #3 DRIVER CKT FOR RESISTANCE. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN IDLE AIR CONTROL MOTOR #3 DRIVER CIRCUIT.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
833

N TEST NS-7C O S T A R T T E S T S
AB BODY

CHECKING IDLE AIR CONTROL MOTOR
AN AND BR BODIES

Perform TEST NS-7A Before Proceeding

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
834

FIG. 4

TEST NS-7C

CHECKING IDLE AIR CONTROL MOTOR

Perform TEST NS-7A Before Proceeding

N O S T A R T T E S T S

START TEST NS-7C.

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL INFO 4.0

IS ANY TERMINAL DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR TERMINAL(S) FOR DAMAGE, PUSHOUT, OR MISWIRING.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

TEST THE IDLE AIR CONTROL MOTOR #1 DRIVER CKT FOR RESISTANCE. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN IDLE AIR CONTROL MOTOR #1 DRIVER CIRCUIT.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
835

N TEST NS-7D O S T A R T T E S T S
AB BODY

CHECKING IDLE AIR CONTROL MOTOR
AN AND BR BODIES

Perform TEST NS-7A Before Proceeding

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
836

FIG. 4

TEST NS-7D

CHECKING IDLE AIR CONTROL MOTOR

Perform TEST NS-7A Before Proceeding

N O S T A R T T E S T S

START TEST NS-7D.

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL ONFO 4.0

IS ANY TERMINAL DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR TERMINAL(S) FOR DAMAGE, PUSHOUT, OR MISWIRING.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

TEST THE IDLE AIR CONTROL MOTOR #4 DRIVER CKT FOR RESISTANCE. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN IDLE AIR CONTROL MOTOR #4 DRIVER CIRCUIT.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
837

N TEST NS-7E O S T A R T T E S T S
AB BODY

CHECKING IDLE AIR CONTROL MOTOR
AN AND BR BODIES

Perform TEST NS-7A Before Proceeding

FIG. 1
XJ BODY ZJ BODY

FIG. 2

FIG. 3
838

FIG. 4

TEST NS-7E

CHECKING IDLE AIR CONTROL MOTOR

Perform TEST NS-7A Before Proceeding

N O S T A R T T E S T S

START TEST NS-7E.

KEY OFF. DISCONNECT THE POWERTRAIN CONTROL MODULE CONNECTOR.** SEE GENERAL INFO 4.0

IS ANY TERMINAL DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR TERMINAL(S) FOR DAMAGE, PUSHOUT, OR MISWIRING.*

NO

USE AN OHMMETER IN THE FOLLOWING STEP.

TEST THE IDLE AIR CONTROL MOTOR #2 DRIVER CKT FOR RESISTANCE. FIG. 1, 2, 3 OR 4

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

NO

REPAIR THE OPEN IDLE AIR CONTROL MOTOR #2 DRIVER CIRCUIT.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
839

N TEST NS-8A O S T A R T T E S T S

REPAIRING A START AND STALL CONDITION

Perform TEST NS-7A Before Proceeding

NOTES

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
840

TEST NS-8A

REPAIRING A START AND STALL CONDITION

Perform TEST NS-7A Before Proceeding

N O S T A R T T E S T S

At this point in the diagnostic test procedure, you have determined that all of the engine electrical systems are operating as designed; therefore, they are not the cause of the start and stall problem. The following additional items should be checked as possible mechanical causes of the no start condition. Any one or more of these items can produce a no start condition; none can be overlooked as a possible cause. 1. DISTRIBUTOR POSITION − must be within specifications* 2. ENGINE VALVE TIMING − must be within specifications 3. ENGINE COMPRESSION − must be within specifications 4. ENGINE EXHAUST − must be free of any restrictions 5. ENGINE PCV SYSTEM − must flow freely 6. ENGINE DRIVE SPROCKETS − must be properly positioned 7. FUEL − must be free of contamination 8. ENGINE SECONDARY IGNITION CHECK − must exhibit a normal scope pattern Always look for any Technical Service Bulletins that may relate to this condition. Checking Distributor Position With DRB Connect the DRB to the Data Link Connector and select the set SYNC from the menu. WARNING: The following test will be performed with the engine running: avoid contact with rotating components. Start the engine and observe the DRB display. When the distributor is correctly positioned, the IN RANGE message should appear along with 0°. If the distributor needs to be adjusted, loosen the distributor hold-down clamp bolt. Rotate the distributor until reading is as close to 0° as possible and the IN RANGE message is displayed. Tighten the clamp bolt to 22.5 N⅐m (200 in. lbs.) torque. NOTE: Setting the distributor position does not adjust the ignition timing. Ignition timing values are determined by the powertrain control module.

841

N TEST NS-9A O S T A R T T E S T S
AB BODY

REPAIRING A NO CRANK CONDITION
AN BODY

Perform TEST NS SEL Before Proceeding

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
842

TEST NS-9A

REPAIRING A NO CRANK CONDITION

Perform TEST NS SEL Before Proceeding

N O S T A R T T E S T S

START TEST NS-9A.

IS THE VEHICLE EQUIPPED WITH A MANUAL TRANSMISSION?

YES

PERFORM TEST NS-9B.

NO

ENSURE THE TRANSMISSION IS IN PARK.

WITH THE DRB, SELECT INPUTS/OUTPUTS AND READ THE PARK/NEUTRAL POSITION.

DOES THE DRB READ P/N?

NO

NOTE: THE PARK/NEUTRAL SWITCH SENSE CIRCUIT IS OPEN.

YES

PERFORM TEST TC-114A.

DISCONNECT THE STARTER RELAY CONNECTOR.** SEE GENERAL INFO 4.6

WITH A VOLTMETER, MEASURE THE FUSED B(+) CIRCUIT AT THE RELAY CONN. FIG. 1, 2, 3, 4 OR 5

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+) CIRCUIT.*

YES

WITH A VOLTMETER, MESURE THE IGNITION SWITCH OUTPUT CKT AT RELAY CONN. FIG. 1, 2, 3, 4 OR 5

WHILE OBSERVING VOLTMETER, HOLD IGNITION KEY IN THE START POSITION.

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN IGNITION SWITCH OUTPUT CKT.*

YES

WARNING: THE TRANS MUST BE IN PARK AND THE PARKING BRAKE MUST BE ON FOR THE NEXT STEP.

WARNING: THE ENGINE MAY BE CRANKED IN THE NEXT STEP. KEEP AWAY FROM MOVING ENGINE PARTS.

BRIEFLY CONNECT A JUMPER WIRE BETWEEN STARTER RLY FUSED (B+) & OUTPUT CKTS. FIG. 1, 2, 3, 4 OR 5

PERFORM TEST NS-9C.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
843

N TEST NS-9B O S T A R T T E S T S
AB BODY

REPAIRING A NO CRANK CONDITION
AN BODY

Perform TEST NS-9A Before Proceeding

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
844

TEST NS-9B

REPAIRING A NO CRANK CONDITION

Perform TEST NS-9A Before Proceeding

N O S T A R T T E S T S

START TEST NS-9B.

DISCONNECT THE STARTER RELAY.** SEE GENERAL INFO 4.6

WITH AN OHMMETER, MEASURE THE GROUND CIRCUIT. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN STARTER RELAY GROUND CIRCUIT.*

NO

WITH A VOLTMETER, MEASURE THE FUSED B(+) CIRCUIT. FIG. 1, 2, 3, 4 OR 5

IS THE VOLTAGE BELOW 10.0 VOLTS?

YES

REPAIR THE OPEN FUSED B(+) CIRCUIT.*

NO

WITH A VOLTMETER, MEASURE THE IGNITION SWITCH OUTPUT CIRCUIT. FIG. 1, 2, 3, 4 OR 5

WHILE OBSERVING VOLTMETER, HOLD IGNITION KEY IN THE START POSITION AND DEPRESS CLUTCH PEDAL

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

PERFORM TEST NS-9C.

NO

DISCONNECT THE CLUTCH PEDAL POSITION SWITCH LOCATED ON CLUTCH MASTER CYLINDER.

JUMPER ACROSS THE CLUTCH PEDAL POSITION SWITCH WITH A JUMPER WIRE.

HOLD THE IGNITION KEY IN THE START POSITION.

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

REPLACE THE CLUTCH MASTER CYLINDER.*

NO

CONTINUE TEST NS-9B ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
845

N TEST NS-9B O S T A R T T E S T S

CONTINUED REPAIRING A NO CRANK CONDITION

Perform TEST NS-9A Before Proceeding

NOTES

846

TEST NS-9B

CONTINUED REPAIRING A NO CRANK CONDITION

Perform TEST NS-9A Before Proceeding

N O S T A R T T E S T S

TEST NS-9B CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE JUMPER WIRE.

WITH A VOLTMETER, MEASURE THE IGNITION SWITCH OUTPUT AT THE CLUTCH PEDAL POSITION SWITCH.

CHECK FOR VOLTAGE AT THE CONNECTOR, WITH THE IGNITION SWITCH IN THE START POSITION.

IS THE VOLTAGE AT THE CLUTCH SWITCH CONNECTOR ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN IGNITION SWITCH OUTPUT.*

YES

REPAIR THE OPEN IGNITION SWITCH OUTPUT CIRCUIT BETWEEN THE CLUTCH SWITCH AND RELAY.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
847

N TEST NS-9C O S T A R T T E S T S
AB BODY

REPAIRING A NO CRANK CONDITION
AN BODY

Perform TEST NS-9A OR NS-9B Before Proceeding

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
848

TEST NS-9C

REPAIRING A NO CRANK CONDITION

Perform TEST NS-9A OR NS-9B Before Proceeding

N O S T A R T T E S T S

START TEST NS-9C.

DID THE STARTER MOTOR CRANK THE ENGINE?

YES

CONTINUE TEST NS-9C ON THE NEXT PAGE.

NO

NOTE IF THE STARTER SOLENOID CLICKED WHEN THE JUMPER WIRE WAS CONNECTED.

DISCONNECT THE JUMPER WIRE.

DISCONNECT STARTER RELAY OUTPUT WIRE FROM THE STARTER SOLENOID.** SEE GENERAL INFO 4.2

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE RESISTANCE OF THE STARTER RELAY OUTPUT CIRCUIT...

FROM THE RELAY TO THE SOLENOID CONNECTOR. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.O OHMS?

NO

REPAIR THE OPEN STARTER RELAY OUTPUT CKT.*

YES

REINSTALL THE STARTER RELAY.

CHECK THE BATTERY CABLES FOR HIGH RESISTANCE.(USE SERVICE MANUAL PROCECURE)

DID EITHER BATTERY CIRCUIT HAVE A VOLTAGE DROP GREATER THAT 0.2 VOLT? NO

YES

REPAIR THE BATTERY CIRCUIT FOR HIGH RESISTANCE.*

DID THE STARTER SOLENOID CLICK WHEN THE JUMPER WIRE WAS PREVIOUSLY CONNECTED? YES

NO

REPLACE THE STARTER SOLENOID.*

REPAIR MECHANICAL CONDITION PREVENTING THE STARTER MOTOR FROM CRANKING.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
849

N TEST NS-9C O S T A R T T E S T S
AB BODY

CONTINUED - REPAIRING A NO CRANK CONDITION
AN BODY

Perform TEST NS-9A OR NS-9B Before Proceeding

FIG. 1
BR BODY XJ BODY

FIG. 2

FIG. 3
ZJ BODY

FIG. 4

FIG. 5
850

TEST NS-9C

CONTINUED - REPAIRING A NO CRANK CONDITION

Perform TEST NS-9A OR NS-9B Before Proceeding

N O S T A R T T E S T S

TEST NS-9C CONTINUED FROM THE PREVIOUS PAGE.

IS THE VEHICLE EQUIPPED WITH A MANUAL TRANSMISSION?

YES

NO

WITH AN OHMMETER, MEASURE THE P/N POSITION SWITCH SENSE CIRCUIT...

IN THE STARTER RELAY CONNECTOR. FIG. 1, 2, 3, 4 OR 5

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE STARTER RELAY.*

NO

REPAIR THE OPEN PARK/NEUTRAL SWITCH SENSE CIRCUIT BETWEEN STARTER RELAY AND SPLICE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
851

N TEST NS-10A O S T A R T T E S T S

QUALIFYING A NO START CONDITION (8.0 L ONLY)

Perform TEST NS-SEL Before Proceeding

FIG. 1

FIG. 2
852

TEST NS-10A QUALIFYING A NO START CONDITION (8.0 L ONLY)
Perform TEST NS-SEL Before Proceeding

N O S T A R T T E S T S

START TEST NS-10A.

NOTE: REPAIR ANY DIAGNOSTIC TROUBLE CODES BEFORE PROCEEDING.

TURN IGNITION OFF.

DISCONNECT THE SPARK PLUG CABLE AT SPARK PLUG #1. FIG. 1

INSERT A SPARK TESTER IN THE CABLE TERMINAL. FIG. 2

WHILE CRANKING THE ENGINE FOR 10 SECONDS, WATCH FOR SPARK.

NOTE: CONSIDER 1 OR 2 SPARKS AS A NO SPARK CONDITION.

IS THERE GOOD SPARK?

YES

RECONNECT SPARK PLUG CABLE.

NO

PERFORM TEST NS-2A.

RECONNECT SPARK PLUG CABLE.

DISCONNECT THE SPARK PLUG CABLE AT SPARK PLUG #2.

INSERT A SPARK TESTER IN THE CABLE TERMINAL. FIG. 2

CONTINUE TEST NS-1A ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
853

N TEST NS-10A O S T A R T T E S T S

CONTINUED - QUALIFYING A NO START CONDITION (8.0 L ONLY)

FIG. 1

854

TEST NS-10A CONTINUED - QUALIFYING A NO START CONDITION (8.0 L ONLY)

N O S T A R T T E S T S

TEST NS-10A CONTINUED FROM THE PREVIOUS PAGE.

WHILE CRANKING THE ENGINE FOR 10 SECONDS, WATCH FOR SPARK.

NOTE: CONSIDER 1 OR 2 SPARKS AS A NO SPARK CONDITION.

IS THERE GOOD SPARK?

YES

REPLACE SPARK PLUG CABLE #1.

NO

PERFORM TEST NS-2A.

DISCONNECT THE FRONT IGNITION COIL CONNECTOR.** INSPECT ALL TERMINALS. FIG. 1

IS ANY TERMINAL DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR TERMINAL(S) FOR DAMAGE PUSHOUT, OR MISWIRING.*

NO

CONTINUE TEST NS-1A ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
855

N TEST NS-10A O S T A R T T E S T S

CONTINUED - QUALIFYING A NO START CONDITION (8.0 L ONLY)

FIG. 1

856

TEST NS-10A CONTINUED - QUALIFYING A NO START CONDITION (8.0 L ONLY)

N O S T A R T T E S T S

TEST NS-10A CONTINUED FROM THE PREVIOUS PAGE.

ENSURE KEY IS ON. WITH THE DRB, ACTUATE IGNITION COIL #1.

USING A VOLTMETER, MEASURE THE ASD RELAY OUTPUT CKT IN THE IGNITION COIL CONNECTOR. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN ASD RELAY OUTPUT CKT FROM COIL CONNECTOR TO SPLICE.*

YES

WITH THE DRB, STOP ALL ACTUATIONS.

USING SERVICE MANUAL PROCEDURES, CHECK VALVE TIMING.

IS VALVE TIMING WITHIN SPECIFICATIONS?

NO

REPAIR THE ENGINE VALVE TIMING AS NECESSARY.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
857

N TEST NS-11A O S T A R T T E S T S
AB BODY

CHECKING THE FUEL SYSTEM (CNG)
AN AND BR BODIES

Perform TEST NS-SEL Before Proceeding

FIG. 1
AB BODY AN AND BR BODIES

FIG. 2

FIG. 3
858

FIG. 4

TEST NS-11A CHECKING THE FUEL SYSTEM (CNG)
Perform TEST NS-SEL Before Proceeding

N O S T A R T T E S T S

START TEST NS-11A.

ATTEMPT TO CRANK THE ENGINE.

WAS THE ENGINE ABLE TO CRANK?

NO

PERFORM TEST NS-9A.

YES

TURN IGNITION OFF.

WARNING: READ WARNINGS, DISCLAIMERS,AND SAFETY SECTION IN INTRODUCTION.

NOTE: FUEL CYLINDERS MUST BE AT LEAST 1/4 FULL FOR THE FOLLOWING TEST.

CHECK THE MANUAL FUEL SHUT-OFF VALVE POSITION. FIG. 1 OR 2

IS THE MANUAL FUEL SHUT-OFF VALVE IN THE OPEN POSITION?

NO

OPEN THE MANUAL FUEL SHUT-OFF VALVE.*

YES

CHECK THE FUEL CYLINDER MANUAL CONTROL VALVE(S). FIG. 3 OR 4

THE VALVE(S) SHOULD BE FULLY COUNTERCLOCKWISE WHEN OPEN.

IS THE FUEL CYLINDER MANUAL CONTROL VALVE(S) OPEN?

NO

OPEN FUEL CYLINDER MANUAL CONTROL VALVES.*

YES

TURN IGNITION ON. ACTUATE THE ASD RELAY. CONTINUE TEST NS-11A ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
859

N TEST NS-11A O S T A R T T E S T S

CONTINUED - CHECKING THE FUEL SYSTEM (CNG)

FIG. 1
AN AND BR BODIES

FIG. 2
AB BODY

FIG. 3
860

TEST NS-11A CONTINUED - CHECKING THE FUEL SYSTEM (CNG)

N O S T A R T T E S T S
NO PERFORM TEST NS-12B.

TEST NS-11A CONTINUED FROM THE PREVIOUS PAGE.

TOUCH THE LOW PRESSURE FUEL SHUT-OFF SOLENOID. FIG. 1

DOES THE LOW PRESSURE FUEL SHUT-OFF SOLENOID PULSATE WITH ACTUATION? YES

NO

PERFORM TEST NS-12A.

TOUCH THE HIGH PRESSURE FUEL SHUT-OFF SOLENOID. FIG. 2 OR 3

IS THE HIGH PRESSURE FUEL SHUT-OFF SOLENOID PULSATING WITH ACTUATION? YES

NOTE: THE FUEL GAUGE MUST INDICATE FUEL IS PRESENT BEFORE PERFORMING NEST STEP.

WITH THE DRB, READ FUEL PRESSURE.

IS THE FUEL PRESSURE BELOW 90 PSI?

YES

PERFORM TEST NS-11B.

NO

IS THE FUEL PRESSURE ABOVE 134 PSI?

NO

CONTINUE TEST NS-11A ON THE NEXT PAGE.

YES

CONNECT A 0 TO 300 PSI PRESSURE GAUGE TO FUEL SERVICE PORT. FIG. 1

TURN IGNITION OFF. WITH THE DRB, ACTUATE THE FUEL SYSTEM. IS THE FUEL GAUGE PRESSURE ABOVE 140 PSI? YES REPLACE THE FUEL PRESSURE REGULATOR.*

NO

CONTINUE TEST NS-11A ON THE NEXT PAGE.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
861

N TEST NS-11A O S T A R T T E S T S

CONTINUED - CHECKING THE FUEL SYSTEM (CNG)

FIG. 1

FIG. 2
862

TEST NS-11A CONTINUED - CHECKING THE FUEL SYSTEM (CNG)

N O S T A R T T E S T S
REINSTALL THE FUEL PRESSURE SENSOR.

TEST NS-11A CONTINUED FROM THE PREVIOUS PAGE.

WITH THE DRB, STOP ACTUATOR TEST.

DOES THE VEHICLE HAVE A FUEL PRESSURE SERVICE PORT ON THE FUEL RAIL? FIG. 1 YES

NO

PURGE NATURAL GAS FROM THE FUEL RAIL. SEE GENERAL INFO 9.0

ENSURE THE THROTTLE IS NOT BEING HELD OPEN.

IS THE THROTTLE HELD OPEN?

YES

REPAIR CONDITION THAT HOLDS THE THROTTLE BODY OPEN.*

NO

WITH THE DRB, READ THROTTLE POSITION SENSOR VOLTAGE.

IS THE VOLTAGE ABOVE 1.5 VOLTS?

NO

CONTINUE TEST NS-11A ON THE NEXT PAGE.

YES

DISCONNECT THE THROTTLE POSITION SENSOR CONNECTOR.** SEE GENERAL INFO 4.0

INSPECT THE CONNECTOR FOR PROPER WIRING AND IS FREE OF DIRT. FIG. 2

IS ANY TERMINAL DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR TERMINAL(S) FOR DAMAGE, PUSHOUT, OR MISWIRING.*

NO

REPLACE THE THROTTLE POSITION SENSOR.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
863

N TEST NS-11A O S T A R T T E S T S

CONTINUED - CHECKING THE FUEL SYSTEM (CNG)

AB, AN AND BR BODIES

FIG. 1

864

TEST NS-11A CONTINUED - CHECKING THE FUEL SYSTEM (CNG)

N O S T A R T T E S T S

TEST NS-11A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE INJECTOR #1 CONNECTOR. SEE GENERAL INFO 4.0

WITH THE DRB, ACTUATE ALL SOLENOIDS AND RELAYS.

WITH THE DRB STILL ACTUATING, USE A VOLTMETER TO...

MEASURE THE AUTO SHUTDOWN RELAY OUTPUT CIRCUIT. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN AUTO SHUTDOWN RELAY OUTPUT CIRCUIT FROM INJECTOR TO SPLICE.*

YES

NOTE: THE FUEL PRESSURE MUST BE READ IMMEDIATELY AFTER THE NEXT STEP.

DISCONNECT THE LOW PRESSURE FUEL SHUT-OFF SOLENOID.** SEE GENERAL INFO 4.0

WITH THE DRB, READ THE FUEL PRESSURE.

IS THE FUEL PRESSURE ABOVE 10 PSI?

NO

CONTINUE TEST NS-11A ON THE NEXT PAGE.

YES

RECONNECT THE LOW PRESSURE FUEL SHUT-OFF SOLENOID CONNECTOR.

PERFORM TEST NS-4A.

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
865

N TEST NS-11A O S T A R T T E S T S

CONTINUED - CHECKING THE FUEL SYSTEM (CNG)

FIG. 1

866

TEST NS-11A CONTINUED - CHECKING THE FUEL SYSTEM (CNG)

N O S T A R T T E S T S

TEST NS-11A CONTINUED FROM THE PREVIOUS PAGE.

WITH THE DRB, STOP ACTUATOR TEST.

RECONNECT THE LOW PRESSURE FUEL SHUT-OFF SOLENOID.

WITH THE DRB, ACTUATE ALL SOLENOIDS AND RELAYS.

WITH THE DRB, STOP ACTUATOR TEST AND IMMEDIATELY READ THE FUEL PRESSURE.

IS THE FUEL PRESSURE ABOVE 10 PSI?

YES

PERFORM TEST NS-13A.

NO

REMOVE THE AIR CLEANER ASSEMBLY.

WITH THE DRB, ACTUATE THE FUEL SYSTEM.

HOLD THE THROTTLE OPEN AND LISTEN FOR ESCAPING GAS. FIG. 1

TURN IGNITION OFF. IS ESCAPING GAS HEARD FROM THE THROTTLE AREA? YES ONE OF THE FUEL INJECTORS IS LEAKING.

NO

TURN IGNITION OFF.

REPLACE THE LEAKING FUEL INJECTOR.*

NOTE: THE FUEL LEAK HAS BEEN ISOLATED TO THE FUEL RAIL AREA.

REPAIR THE GAS LEAK AT THE FUEL RAIL.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
867

N TEST NS-11B O S T A R T T E S T S

CHECKING THE FUEL SYSTEM (CNG)
AB BODY

Perform TEST NS-11A Before Proceeding
AN AND BR BODIES

FIG. 1
AN AND BR BODIES BR BODY

FIG. 2

FIG. 3
868

FIG. 4

TEST NS-11B CHECKING THE FUEL SYSTEM (CNG)
Perform TEST NS-11A Before Proceeding

N O S T A R T T E S T S

START TEST NS-11B.

WITH THE DRB, STOP ACTUATION TEST.

DISCONNECT THE FUEL LOW PRESSURE SENSOR CONNECTOR.** SEE GENERAL INFO 4.0

CONNECT JUMPER WIRE FROM FUEL PRESSURE SENSOR SIGNAL TO 5-VOLT SUPPLY CKT. FIG. 1 OR 2

WITH THE DRB, READ CNG FUEL PRESSURE.

IS THE FUEL PRESSURE ABOVE 130 PSI?

NO

CONTINUE TEST NS-11B ON THE NEXT PAGE.

YES

INSPECT ALL FUEL LINES FOR KINK OR RESTRICTION.

IS THERE ANY KINK OR RESTRICTION?

YES

REPAIR KINKED OR RESTRICTED FUEL LINE AS NECESSARY.*

NO

PURGE NATURAL GAS FROM THE FUEL RAIL. TURN IGNITION OFF. SEE GENERAL INFO 9.0

DOES THE VEHICLE HAVE A FUEL PRESSURE SERVICE PORT ON THE FUEL RAIL? NO

YES

CONNECT A FUEL PRESSURE GAUGE TO THE FUEL SERVICE PORT. THEN WITH DRB, ACTUATE FUEL SYSTEM.

REMOVE FUEL PRESS SENSOR & CONNECT A 0-300 PSI PRESS GAUGE TO FUEL RAIL SEE GENERAL INFO 4.0

WITH THE DRB, ACTUATE THE FUEL SYSTEM.

IS THE FUEL PRESSURE ABOVE 90 PSI?

YES

REPLACE THE FUEL PRESSURE SENSOR.*

NO

USING SERVICE MANUAL PROCEDURES, REPLACE THE FUEL FILTER. FIG. 3 OR 4

ATTEMPT TO START THE ENGINE.

DID THE ENGINE START?

YES TEST COMPLETE.

NO

REPLACE THE FUEL PRESSURE REGULATOR.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
869

N TEST NS-11B O S T A R T T E S T S

CONTINUED - CHECKING THE FUEL SYSTEM (CNG)

AN AND BR BODIES

FIG. 1
AB BODY

FIG. 2
870

TEST NS-11B CONTINUED - CHECKING THE FUEL SYSTEM (CNG)

N O S T A R T T E S T S

TEST NS-11B CONTINUED FROM THE PREVIOUS PAGE.

REMOVE JUMPER WIRE.

USING A VOLTMETER, MEASURE THE 5-VOLT SUPPLY CIRCUIT. FIG. 1 OR 2

IS THE VOLTAGE ABOVE 4.5 VOLTS?

NO

REPAIR THE OPEN 5-VOLT SUPPLY CKT FROM FUEL PRESSURE SENSOR TO SPLICE.*

YES

TURN IGNITION OFF.

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

USING AN OHMMETER, MEASURE THE FUEL PRESSURE SENSOR SIGNAL CKT TO GROUND FIG. 1 OR 2

IS THE RESISTANCE ABOVE 5.0 OHMS?

NO

REPAIR THE FUEL PRESSURE SENSOR SIGNAL CKT SHORT TO GROUND.*

YES

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
871

N TEST NS-12A O S T A R T T E S T S
AB BODY

CHECKING THE FUEL RELAYS AND SOLENOIDS
AN BODY

Perform TEST NS-11A Before Proceeding

BR BODY

AB BODY

FIG. 1
AN BODY BR BODY

FIG. 2
872

FIG. 3

TEST NS-12A CHECKING THE FUEL RELAYS AND SOLENOIDS
Perform TEST NS-11A Before Proceeding

N O S T A R T T E S T S

START TEST NS-12A.

TURN IGNITION OFF.

DISCONNECT THE LOW PRESS FUEL SHUT-OFF SOLENOID CONN.** SEE GENERAL INFO 4.2

WITH AN OHMMETER, MEASURE THE GND CIRCUIT IN LOW PRESS SHUT-OFF SOL CONN. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN GROUND FROM LOW PRESSURE SHUT-OFF SOLENOID TO SPLICE.*

YES

WITH THE DRB, ACTUATE GENERATOR FIELD.

WITH A VOLTMETER, MEASURE THE AUTO SHUTDOWN RELAY OUTPUT CIRCUIT. FIG. 1, 2 OR 3

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

REPLACE THE LOW PRESSURE SHUT-OFF SOLENOID.*

NO

TURN IGNITION OFF.

DISCONNECT THE AUTO SHUTDOWN RELAY CONNECTOR.** SEE GENERAL INFO 4.6

WITH A VOLTMETER, MEASURE THE ASD RELAY FUSED B(+) CIRCUIT. FIG. 1, 2 OR 3

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+) CIRCUIT FROM BATTERY TO ASD RELAY.*

YES

USE AN OHMMETER IN THE FOLLOWING STEP.

TEST ASD RLY OUTPUT CKT FROM ASD RLY TO LOW PRESS SHUT-OFF SOLENOID. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE AUTO SHUTDOWN RELAY.*

NO

REPAIR THE OPEN ASD RELAY OUTPUT CIRCUIT FROM LOW PRESSURE SHUT-OFF SOLENOID TO ASD RELAY.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
873

N TEST NS-12B O S T A R T T E S T S
AB BODY

CHECKING THE FUEL RELAYS AND SOLENOIDS
AN BODY

Perform TEST NS-11A Before Proceeding

BR BODY

AB BODY

FIG. 1
AN BODY BR BODY

FIG. 2
874

FIG. 3

TEST NS-12B CHECKING THE FUEL RELAYS AND SOLENOIDS
Perform TEST NS-11A Before Proceeding

N O S T A R T T E S T S

START TEST NS-12B.

TURN IGNITION OFF.

DISCONNECT THE HIGH PRESS FUEL SHUT-OFF SOLENOID CONN.** SEE GENERAL INFO 4.2

USING AN OHMMETER, MEASURE THE GND CIRCUIT IN THE SOLENOID CONN. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN HIGH PRESSURE FUEL SHUT-OFF SOLENOID GROUND CIRCUIT.*

YES

WITH THE DRB, ACTUATE FUEL SYSTEM.

USING A VOLTMETER, MEASURE THE HIGH PRESS SHUT-OFF RELAY OUTPUT CKT. FIG. 1, 2 OR 3

IS THE VOLTAGE ABOVE 10.0 VOLTS?

YES

REPLACE THE FUEL HIGH PRESSURE SHUT-OFF SOLENOID.*

NO

TURN IGNITION OFF.

DISCONNECT THE FUEL HIGH PRESSURE SOLENOID RELAY CONNECTOR.** SEE GENERAL INFO 4.6

USING A VOLTMETER, MEASURE THE SHUT-OFF RELAY FUSED B(+) CIRCUIT. FIG. 1, 2 OR 3

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+) CIRCUIT FROM BATTERY TO THE HIGH PRESSURE SHUT-OFF RELAY.*

YES

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE HIGH PRESSURE SHUT-OFF RELAY...

OUTPUT CIRCUIT FROM THE RELAY TO THE SHUT-OFF SOLENOID. FIG. 1, 2 OR 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

REPLACE THE HIGH PRESSURE FUEL SHUT-OFF SOLENOID RELAY.*

NO

REPAIR THE OPEN HIGH PRESS SHUT-OFF RELAY OUTPUT CIRCUIT FROM SHUT-OFF SOLENOID TO RELAY.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
875

N TEST NS-13A O S T A R T T E S T S

CHECKING FUEL PRESSURE LOSS

Perform TEST NS-SEL Before Proceeding

NOTES

876

TEST NS-13A CHECKING FUEL PRESSURE LOSS
Perform TEST NS-SEL Before Proceeding

N O S T A R T T E S T S
ARE THERE ANY INJECTOR TROUBLE CODES PRESENT? YES PERFORM THE INJECTOR TROUBLE CODE TEST LISTED IN DTC TEST.

START TEST NS-13A.

NOTE: AN INJECTOR CONTROL CIRCUIT IS SHORTED TO GROUND CAUSING THE ENGINE TO FLOOD.

WITH THE DRB, READ DIAGNOSTIC TROUBLE CODES.

NO

DISCONNECT THE POWERTRAIN CONTROL MODULE.** SEE GENERAL INFO 4.0

DISCONNECT ALL THE INJECTOR CONNECTORS SEE GENERAL INFO 4.0

USING AN OHMMETER...

CHECK EACH INJECTOR CONTROL CIRCUIT FOR A SHORT TO GROUND. SEE GENERAL INFO 4.0

WAS ANY INJECTOR CONTROL CIRCUIT SHORTED TO GROUND?

YES

REPAIR THE INJECTOR CONTROL CIRCUIT SHORTED TO GROUND.*

NO

REPLACE THE POWERTRAIN CONTROL MODULE.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
877

N TEST NS-14A O S T A R T T E S T S

CHECKING THE FUEL HEATER RELAY

Perform TEST NS SEL Before Proceeding

FIG. 1

FIG. 2
878

TEST NS-14A CHECKING THE FUEL HEATER RELAY
Perform TEST NS SEL Before Proceeding

N O S T A R T

START TEST NS-14A.

TURN IGNITION ON.

T E S T S
NOTE: TO HEAR CLICK IN THE NEXT STEP, IT MAY BE NECESSARY TO DISCONNECT THE RELAY MORE THAN ONCE. WHILE LISTENING FOR THE RELAY TO CLICK, DISCONNECT THE FUEL HEATER RELAY.** FIG. 1 DID THE RELAY CLICK? YES CONTINUE TEST NS-14A ON THE NEXT PAGE.

NO

USING A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CIRCUIT. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGNITION SWITCH OUTPUT.*

YES

TURN IGNITION OFF.

USING AN OHMMETER, MEASURE THE FUEL HEATER RELAY GROUND CIRCUIT. FIG. 2

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN FUEL HEATER RELAY GROUND CIRCUIT.*

NO

REPLACE THE FUEL HEATER RELAY.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
879

N TEST NS-14A O S T A R T T E S T S

CONTINUED - CHECKING THE FUEL HEATER RELAY

FIG. 1

FIG. 2

FIG. 3

FIG. 4
880

FIG. 5

TEST NS-14A CONTINUED - CHECKING THE FUEL HEATER RELAY

N O S T A R T T E S T S
NO REPAIR THE OPEN FUEL HEATER GROUND CIRCUIT.*

TEST NS-14A CONTINUED FROM THE PREVIOUS PAGE.

USING A VOLTMETER, MEASURE THE FUSED B(+) IN THE HEATER RELAY CONN. FIG. 1

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+) CIRCUIT.*

YES

IGNITION OFF. DISCONNECT THE FUEL HEATER ELECTRICAL CONNECTOR.** FIG. 2

USING AN OHMMETER, MEASURE THE FUEL HEATER GROUND CIRCUIT. FIG. 3

IS THE RESISTANCE BELOW 5.0 OHMS?

YES

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE FUEL HEATER RELAY OUTPUT CIRCUIT...

FROM THE RELAY TO THE HEATER CONNECTOR. FIG. 4

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN FUEL HEATER RELAY OUTPUT CIRCUIT.*

NO

DISCONNECT THE FUEL HEATER ELEMENT CONNECTOR.** INSPECT ALL TERMINALS. FIG. 2

IS ANY TERMINAL DAMAGED, PUSHED OUT, OR MISWIRED?

YES

REPAIR ANY TERMINAL(S) FOR DAMAGE, PUSHOUT, OR MISWIRING.*

NO

NOTE: THE FUEL HEATER TEMPERATURE MUST BE BELOW 40F FOR THE NEXT STEP.

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE FUEL HEATER. FIG. 2 AND 5

IS THE RESISTANCE ABOVE 10.0 OHMS?

NO

THE NO START CONDITION IS DUE TO A MECHANICAL PROBLEM. SEE SERVICE MANUAL FOR REPAIRS.

YES

REPLACE THE FUEL HEATER.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
881

N TEST NS-15A O S T A R T T E S T S

CHECKING THE FUEL SHUTDOWN RELAY AND SOLENOID (DIESEL)

Perform TEST NS-SEL Before Proceeding

FIG. 1

FIG. 2
882

TEST NS-15A CHECKING THE FUEL SHUTDOWN RELAY AND SOLENOID (DIESEL)
Perform TEST NS-SEL Before Proceeding

N O S T A R T T E S T S

START TEST NS-15A.

OBSERVE THE EXTENSION OF THE FUEL SHUTDOWN SOLENOID PLUNGER. FIG. 1

NOTE: DO NOT TURN THE IGNITION OFF AFTER CRANKING THE ENGINE FOR 3 SECONDS IN THE NEXT STEP.

CRANK THE ENGINE.

INSPECT THE FUEL SHUTDOWN SOLENOID PLUNGER. FIG. 1

IS THE PLUNGER RETRACTED?

THE NO START YES CONDITION IS DUE TO A MECHANICAL PROBLEM. SEE SERVICE MANUAL FOR REPAIRS.

NO

TURN IGNITION ON.

MANUALLY RETRACT THE FUEL SHUTDOWN SOLENOID PLUNGER AND THEN RELEASE.

DOES THE PLUNGER REMAIN RETRACTED WHEN IT IS NO LONGER MANUALLY HELD IN? NO

YES

TEST NS-15A CONTINUED ON THE NEXT PAGE.

DISCONNECT THE FUEL SHUTDOWN SOLENOID.** SEE GENERAL INFO 4.0

USING A VOLTMETER, MEASURE THE FUSED IGN SWITCH OUTPUT CIRCUIT. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED IGN. SWITCH OUTPUT CKT.*

YES

TURN IGNITION OFF.

USING AN OHMMETER, MEASURE THE FUEL SHUTDOWN SOLENOID GROUND CKT.

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN GROUND CIRCUIT.*

YES

REPLACE THE FUEL SHUTDOWN SOLENOID.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
883

N TEST NS-15A O S T A R T T E S T S

CONTINUED - CHECKING THE FUEL SHUTDOWN RELAY AND SOLENOID (DIESEL)

FIG. 1

FIG. 2
884

TEST NS-15A CONTINUED - CHECKING THE FUEL SHUTDOWN RELAY AND SOLENOID (DIESEL)

N O S T A R T T E S T S

TEST NS-15A CONTINUED FROM THE PREVIOUS PAGE.

DISCONNECT THE FUEL SHUTDOWN SOLENOID ELECTRICAL CONNECTOR.** FIG. 1

USING A VOLTMETER, MEASURE THE FUEL SHUTDOWN RELAY OUTPUT CIRCUIT. FIG. 2

WHILE CRANKING THE ENGINE, READ VOLTAGE.

WAS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

CONTINUE TEST NS-15A ON THE NEXT PAGE.

YES

TURN IGNITION OFF.

USING AN OHMMETER, MEASURE THE FUEL SHUTDOWN SOLENOID GROUND CIRCUIT. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN GROUND CIRCUIT.*

YES

REPLACE THE FUEL SHUTDOWN SOLENOID.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
885

N TEST NS-15A O S T A R T T E S T S

CONTINUED - CHECKING THE FUEL SHUTDOWN RELAY AND SOLENOID (DIESEL)

FIG. 1

FIG. 2
886

TEST NS-15A CONTINUED - CHECKING THE FUEL SHUTDOWN RELAY AND SOLENOID (DIESEL)

N O S T A R T T E S T S

TEST NS-15A CONTINUED FROM THE PREVIOUS PAGE.

IGNITION OFF. DISCONNECT THE FUEL SHUTDOWN RELAY.** FIG. 1

USE AN OHMMETER IN THE FOLLOWING STEP.

MEASURE THE FUEL SHUTDOWN RELAY OUTPUT CIRCUIT FOR RESISTANCE. FIG. 2

IS THE RESISTANCE BELOW 5.0 OHMS?

NO

REPAIR THE OPEN FUEL SHUTDOWN RELAY OUTPUT CIRCUIT.*

YES

USING A VOLTMETER, MEASURE THE FUSED B(+) CIRCUIT IN THE SHUTDOWN RELAY CONN. FIG. 2

IS THE VOLTAGE ABOVE 10.0 VOLTS?

NO

REPAIR THE OPEN FUSED B(+).*

YES

USING AN OHMMETER, MEASURE THE SHUTDOWN RELAY GROUND CIRCUIT IN RELAY CONNECTOR. FIG. 2

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN RELAY GROUND CIRCUIT.*

NO

DISCONNECT THE STARTER RELAY.** FIG. 3

USING AN OHMMETER, MEASURE THE RESISTANCE OF THE STARTER RELAY OUTPUT CIRCUIT...

FROM THE FUEL SHUTDOWN RELAY TO THE STARTER RELAY. FIG. 3

IS THE RESISTANCE ABOVE 5.0 OHMS?

YES

REPAIR THE OPEN STARTER RELAY OUTPUT CIRCUIT.*

NO

REPLACE THE FUEL SHUTDOWN RELAY.*

*Perform Verification TEST VER-1A.

**Check connectors - Clean / repair as necessary.
887

V TEST VER-1A NO START VERIFICATION E R I Inspect the vehicle to ensure that all engine components are connected. Reassemble and reconnect F components as necessary. I C Inspect the engine for contamination. If it is contaminated, change the oil and filter. A T Attempt to start the engine. I If the engine is unable to start, look for any Technical Service Bulletins that may relate to this O condition. Return to DTC TEST if necessary. N
The repair is now complete.

T E S T S

888

TEST VER-2A ROAD TEST VERIFICATION
Inspect the vehicle to ensure that all engine components are connected. Reassemble and reconnect all components as necessary. If this verification procedure is being performed after a NO TROUBLE CODE test, do the following: 1. Check to see if the initial symptom still exists. 2. If the initial or another symptom exists, the repair is not complete. Check all pertinent Technical Service Bulletins and return to DTC TEST, if necessary. If this verification procedure is being performed after an OBDII trouble code test, perform VER-5. For all other trouble codes, continue with this verification. For previously read trouble codes that have not been dealt with, return to DTC TEST and follow the path specified; otherwise continue. If the powertrain control module has not been changed: 1. Connect the DRB to the PCM data link connector and erase trouble codes. 2. With the DRB, reset all values in the adaptive memory. 3. Disconnect the DRB. Ensure no trouble code remains by doing the following: 1. If this test is for an A/C Relay Control Circuit Code, drive the vehicle for at least five minutes with the A/C on. For some of the drive, go at least 40 mph; at some point stop the car and turn the engine off for 10 seconds or more; then restart and continue. Ensure the transmission shifts through all gears. Upon completion of the road test, turn the engine off, and read trouble codes with the DRB. 2. If the repaired code has reset, the repair is not complete. Check all related Technical Service Bulletins and return to DTC TEST if necessary. If another trouble code has set, return to DTC TEST and follow the path specified for that trouble code. If there are no trouble codes, the repair was successful and is now complete.

V E R I F I C A T I O N T E S T S

889

V TEST VER-3A CHARGING VERIFICATION E R I Inspect the vehicle to ensure that all engine components are connected. Reassemble and reconnect F components as necessary. I C If the powertrain control module has been changed, do the following: A 1. If the vehicle is equipped with a factory theft alarm, start the vehicle at least 20 times so that the T alarm system may be activated when desired. I O Connect the DRB to the PCM data link connector and erase the codes. N
Ensure no other charging system problems remain by doing the following:

T E S T S

1. Start the engine. 2. Raise the engine speed to 2000 rpm for at least 30 seconds. 3. Allow the engine to idle. 4. Turn the engine off. 5. Turn the ignition key on. 6. With the DRB, read trouble code messages. If the repaired code has reset, or another one has set, check all pertinent Technical Service Bulletins and return to DTC TEST if necessary. If there are no codes, the repair is now complete.

890

TEST VER-4A SPEED CONTROL VERIFICATION
Inspect the vehicle to ensure that all engine components are connected. Reassemble and reconnect components as necessary. If the powertrain control module has been changed, do the following: 1. If the vehicle is equipped with a factory theft alarm, start the vehicle at least 20 times so that the alarm system may be activated when desired. Connect the DRB to the PCM data link connector and erase the codes. Ensure no other speed control problems remain by doing the following: 1. Road test the vehicle at a speed above 35 mph. 2. Turn the speed control ON/OFF switch to the ON position. 3. Depress and release the SET switch. If the speed control did not engage, the repair is not complete.* 4. Quickly depress and release the RESUME/ACCEL switch. If the vehicle speed did not increase by 2 mph, the repair is not complete.* 5. Using caution, depress and release the brake pedal. If the speed control did not disengage. The repair is not complete.* 6. Bring the vehicle speed back up to 35 mph. 7. Depress the RESUME/ACCEL switch. If the speed control did not resume the previously set speed, the repair is not complete.* 8. Hold down the SET switch. If the vehicle did not decelerate, the repair is not complete.* 9. Ensure the vehicle speed is greater than 35 mph and release the SET switch. If the vehicle did not adjust and set a new vehicle speed, the repair is not complete.* 10. Turn on the ON/OFF switch to the OFF position. If the speed control did not disengage, the repair is not complete.* If the vehicle successfully passed all of the previous tests, the speed control system is now functioning as designed. The repair is now complete. *Check for Technical Service Bulletins that pertain to this speed control problem and then, if necessary, return to DTC TEST.

V E R I F I C A T I O N T E S T S

891

V TEST VER-5A ROAD TEST FOR OBDII TROUBLE CODES E R I Inspect the vehicle to ensure that all engine components are connected. Reassemble and reconnect F components as necessary. I C If there are any existing diagnostic trouble codes that have not been repaired, perform DTC TEST A and follow the path specified. After all diagnostic trouble codes have been repaired, return to TEST T VER-5A and run the monitor for the previously repaired OBDII trouble code. I 1. Connect the DRB to the data link connector. O N 2. Ensure the fuel tank has at least a quarter tank of fuel. T E S T S
3. Turn the air conditioning off. 4. The proper way to verify that the trouble code has been repaired is to allow the powertrain control module to run the monitor. The technician can see the monitor using the DRBIII. The enabling conditions must be met before the powertrain control module will run the monitor. The enabling conditions for the covered OBDII codes can be found in each trouble code test. Read the enabling conditions for the trouble code that was repaired. The enabling conditions are different for each OBDII code. 5. With the DRBIII, monitor the pre-test enabling conditions until all conditions have been met. Once the enabling conditions have been met, monitor the appropriate OBDII monitor with the DRBIII. 6. If the repaired OBDII trouble code has reset or was seen in the OBDII monitor while on the road test, the repair is not complete. Check for any related Technical Service Bulletins and return to DTC TEST. — If another trouble code has set, return to DTC TEST and follow the path specified for that trouble code. — If there are no trouble codes, the repair was successful and is now complete.

892

8.0

MAINTENANCE AND SERVICE INFORMATION

There is no specific maintenance or service information in this manual. Refer to the appropriate service manual for information about repair and replacement procedures. When replacing a blown fuse, it is important to use only a fuse having the correct amperage rating. The use of a fuse with a rating other than indicated may result in a dangerous electrical system overload. If a properly rated fuse continues to blow, it indicates a problem in the circuit that must be corrected.

G E N E R A L I N F O R M A T I O N

9.0 9.1
1. 2. 3. 4. 5. 6.

SPECIFICATIONS Fuel System Release Procedure (Gasoline)
Loosen the fuel filler cap. Remove the fuel pump relay. Start and run engine until it stalls. Attempt to restart the engine until it will no longer run. Ensure the ignition key is off. If the vehicle is equipped with a fuel pressure test port perform the following steps. For all others go to number 7 below. Remove the protective cap from the fuel pressure test port. Use the hose with fitting, from pressure tool set 5069. Place the open end of the fuel pressure release hose, with gauge removed, into an approved gasoline container. c. Place a shop towel under the fuel pressure test port. d. Connect the fitting end of the fuel hose to the fuel pressure test port. e. After all fuel pressure is relieved, remove hose and reinstall test port cap. 7. This step is for engines without a fuel pressure test port. a. Unplug the connector from any injector. b. Attach jumper wires to both pins on the injector. c. Attach the other end of one jumper wire to a good ground. d. Touch the loose end of the remaining jumper wire to B+ for no more than 4 seconds. Repeat this twice. 8. With fuel pressure relieved the fuel system can now be opened for required work. Continue to use caution, fuel leakage is still possible. a. b.

9.2 9.2.1
1. 2. 3.

Fuel System Pressure Release Procedure (CNG) Fuel Line Pressure Release Procedure
Close the fuel control valves on all cylinder(s) by turning the valves completely clockwise. Ensure the manual shut-off valve is in the open position. The valve is open when the handle is parallel with the fuel tubes. Start or attempt to start the engine. If the engine runs, let it run until it runs out of fuel. Attempt to start the engine by cranking for 6 seconds.

893

G E N E R A L I N F O R M A T I O N

4. 5.

Pausing 10 seconds between attempts, repeat step 3 two more times. If the check valve or fuel fill receptacle is to be serviced, slowly loosen the inlet side of the fuel fill tube fitting at the check valve until fuel has purged.

WARNING: THE FUEL CYLINDERS STILL CONTAIN HIGH-PRESSURE FUEL.

9.2.2
1. 2. 3. 4. 5.

Fuel Cylinder Pressure Release Procedure
Close the fuel control valves on the cylinders not being serviced by turning the valves completely clockwise. Ensure the manual shut-off valve is in the open position. The valve is open when the handle is parallel with the fuel tubes. Start the engine and let it run until the fuel is depleted. Attempt to start the engine by cranking for 6 seconds. Pausing 10 seconds between attempts, repeat steps 3 and 4 two more times.

WARNING: THE FUEL CYLINDERS THAT ARE NOT BEING SERVICED STILL CONTAIN HIGH-PRESSURE FUEL.

894

10.0 10.1

SCHEMATIC DIAGRAMS 1996 Dodge 2.5L JTEC System

G E N E R A L I N F O R M A T I O N

895

G E N E R A L I N F O R M A T I O N

10.2

1996 Jeep XJ 2.5L JTEC System

896

10.3

1996 Jeep XJ 4.0L JTEC System

G E N E R A L I N F O R M A T I O N

897

G E N E R A L I N F O R M A T I O N

10.4

1996 Jeep ZJ 4.0L JTEC System

898

10.5

1996 Dodge 3.9L JTEC System

G E N E R A L I N F O R M A T I O N

899

G E N E R A L I N F O R M A T I O N

10.6

1996 Dodge 5.2/5.9L JTEC System

900

10.7

1996 Jeep ZJ 5.2L JTEC System

G E N E R A L I N F O R M A T I O N

901

G E N E R A L I N F O R M A T I O N

10.8

1996 Dodge 5.9L-HD JTEC System

902

10.9

1996 Dodge 5.9L Cummins Diesel JTEC System

G E N E R A L I N F O R M A T I O N

903

G E N E R A L I N F O R M A T I O N

10.10

1996 Dodge 8.0L V10-MD System

904

10.11

1996 Dodge 8.0L V10-HD System

G E N E R A L I N F O R M A T I O N

905

G E N E R A L I N F O R M A T I O N

10.12

1996 Dodge 5.2L CNG, AB, AN, and BR System

906

11.0

REQUIRED TOOLS AND EQUIPMENT
DRB (diagnostic read-out box) fuel line adapters 6541, 6539, 6631 or 6923 fuel pressure test kit 5069 fuel pressure test kit C-4799-B Diesel only: fuel pressure test kit 6977 jumper wires ohmmeter oscilloscope vacuum gauge voltmeter pressure gauge (0-300 psi)

G E N E R A L I N F O R M A T I O N

12.0

GLOSSARY OF TERMS
backfire, popback CKP CMP - Fuel ignites in either the intake or the exhaust system.

- crank position sensor - camshaft position sensor - a steady pulsation or the inability of the engine to maintain a consistent rpm

cuts out, misses DLC

- data link connector (previously called ‘‘engine diagnostic connector’’)

detonation, spark knock - a mild to severe ping, especially under loaded engine conditions ECT EGR - engine coolant temperature sensor - exhaust gas recirculation valve and system - previously callled ‘‘alternator’’ - The engine takes longer than usual to start, even though it is able to crank normally. - There is a momentary lack of response when the throttle is opened. This can occur at all vehicle speeds. If it is severe enough, the engine may stall.

generator hard start

hesitation, sag, stuble

IAT IAC JTEC

- intake air temperature sensor - idle air control valve - Combined engine and transmission control module

lack of power, sluggish - The engine has less than expected power, with little or no increase in vehicle speed when the throttle is opened. MAP MTV - manifold absolute pressure sensor - manifold tuning valve

MVLPS - manual valve lever position switch (previously called ‘‘park/neutral switch’’) O2S O2SR - oxygen sensor (left oxygen sensor when there are two sensors) - right oxygen sensor
907

G E N E R A L I N F O R M A T I O N
12.1

PCM PCV

- powertrain control module - positive crankcase ventilation

poor fuel economy - There is significantly less fuel mileage than other vehicles of the same design and configuration. rough, unstable, or erratic idle stalling - The engine runs unevenly at idle and causes the engine to shake if it is severe enough. The engine idle rpm may vary (called ‘‘hunting’’). This condition may cause stalling if it is severe enough. start & stall - The engine starts but immediately dies. surge TPS VSS - engine rpm fluctuation without corresponding change in throttle position sensor - throttle position sensor - vehicle speed sensor

Body Codes Defined

CARS F24S FJ22 GS JA Eagle Talon Chrysler Sebring Dodge Avenger Chrysler Grand Voyager Chrysler Ram Van Chrysler Cirrus Plymouth Dodge Stratus Chrysler Sebring Convertible Chrysler Concorde Chrysler LHS Chrysler New Yorker Dodge Intrepid Eagle Vision

NS

PL SR27 SR29

Chrysler Town and Country Dodge Caravan / Grand Caravan Plymouth Voyager / Grand Voyager Dodge Neon Plymouth Neon Dodge Viper Roadster Dodge Viper Coupe

JX LH

TRUCKS AB AN BR BT Dodge Ram 150, 250, 350 (Van / Wagon) Dodge Dakota Dodge Ram 1500, 2500, 3500 (Pickup) Dodge Ram 1500, 2500, 3500 (Cab) TJ XJ ZJ Jeep Wrangler Jeep Cherokee Jeep Grand Cherokee

908

NOTES

G E N E R A L I N F O R M A T I O N

909