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Diagnostic Trouble Code Definitions

DIAGNOSTIC TROUBLE CODE MESSAGES & CODES

Generic Scan Tool Code ⁽¹⁾

DRBIII® Scan Tool Message

1/1 O2 SENSOR HEATER CIRCUIT LOW

1/1 O2 SENSOR HEATER CIRCUIT HIGH

1/2 O2 SENSOR HEATER CIRCUIT LOW

1/2 O2 SENSOR HEATER CIRCUIT HIGH

2/1 O2 SENSOR HEATER CIRCUIT LOW

2/1 O2 SENSOR HEATER CIRCUIT HIGH

BATTERY TEMP SENSOR PERFORMANCE

MAP SENSOR VOLTAGE TOO LOW

MAP SENSOR VOLTAGE TOO HIGH

INTAKE AIR TEMP PERFORMANCE

INTAKE AIR TEMP SENSOR VOLTAGE LOW

INTAKE AIR TEMP SENSOR VOLTAGE HIGH

ECT SENSOR VOLTAGE TOO LOW

ECT SENSOR VOLTAGE TOO HIGH

TPS VOLTAGE DOES NOT AGREE WITH MAP

THROTTLE POSITION SENSOR VOLTAGE LOW

THROTTLE POSITION SENSOR VOLTAGE HIGH

CLOSED LOOP TEMP NOT REACHED

1/1 O2 SENSOR SHORTED TO GROUND

1/1 O2 SENSOR SHORTED TO VOLTAGE

1/1 O2 SENSOR SLOW RESPONSE

1/1 O2 SENSOR HEATER FAILURE

1/2 O2 SENSOR HEATER CIRCUIT MALFUNCTION

1/2 O2 SENSOR SHORTED TO GROUND

1/2 O2 SENSOR SHORTED TO VOLTAGE

1/2 O2 SENSOR SLOW RESPONSE

1/2 O2 SENSOR HEATER FAILURE

2/1 O2 SENSOR SHORTED TO GROUND

2/1 O2 SENSOR SHORTED TO VOLTAGE

2/1 O2 SENSOR SLOW RESPONSE

2/1 O2 SENSOR HEATER FAILURE

2/2 O2 SENSOR SHORTED TO GROUND

2/2 O2 SENSOR SHORTED TO VOLTAGE

2/2 O2 SENSOR SLOW RESPONSE

2/2 O2 SENSOR HEATER FAILURE

1/1 FUEL SYSTEM LEAN

1/1 FUEL SYSTEM RICH

2/1 FUEL SYSTEM LEAN

2/1 FUEL SYSTEM RICH

INJECTOR #1 CONTROL CIRCUIT

INJECTOR #2 CONTROL CIRCUIT

INJECTOR #3 CONTROL CIRCUIT

INJECTOR #4 CONTROL CIRCUIT

INJECTOR #5 CONTROL CIRCUIT (4.0L)

INJECTOR #6 CONTROL CIRCUIT (4.0L)

MULTIPLE CYLINDER MISFIRE

CYLINDER #1 MISFIRE

CYLINDER #2 MISFIRE

CYLINDER #3 MISFIRE

CYLINDER #4 MISFIRE

CYLINDER #5 MISFIRE (4.0L)

CYLINDER #6 MISFIRE (4.0L)

NO CRANK REFERENCE SIGNAL AT PCM

NO CAM SIGNAL AT PCM

IGNITION COIL #1 PRIMARY CIRCUIT (2.5L)

IGNITION COIL #1 PRIMARY CIRCUIT (4.0L)

IGNITION COIL #2 PRIMARY CIRCUIT (4.0L)

IGNITION COIL #3 PRIMARY CIRCUIT (4.0L)

1/1 CATALYTIC CONVERTER EFFICIENCY

2/1 CATALYTIC CONVERTER EFFICIENCY

EVAP PURGE FLOW MONITOR FAILURE

EVAP LEAK MONITOR MEDIUM LEAK DETECTED

EVAP PURGE SOLENOID CIRCUIT

EVAP LEAK MONITOR LARGE LEAK DETECTED

EVAP LEAK MONITOR SMALL LEAK DETECTED

FUEL LEVEL UNIT NO CHANGE OVER MILES

FUEL LEVEL UNIT NO CHANGE OVER TIME

FUEL LEVEL SENDING UNIT VOLTS TOO LOW

FUEL LEVEL SENSOR VOLTS TOO HIGH

NO VEHICLE SPEED SENSOR SIGNAL

IDLE AIR CONTROL MOTOR CIRCUITS

OIL PRESSURE SENSOR VOLTS LOW

OIL PRESSURE SENSOR VOLTS HIGH

POWER STEERING SWITCH FAILURE

PCM INTERNAL CONTROLLER FAILURE

P0622 ⁽²⁾

GENERATOR FIELD NOT SWITCHING PROPERLY

A/C CLUTCH RELAY CIRCUIT

P0740 ⁽³⁾

TORQ CONV CLU, NO RPM DROP AT LOCKUP

P0743 ⁽³⁾

TORQUE CONVERTER CLUTCH SOLENOID/TRANS RELAY CKT

1/1 O2 SENSOR SLOW DURING CATALYST MONITOR

2/1 O2 SENSOR SLOW DURING CATALYST MONITOR

ENGINE IS COLD TOO LONG

FUEL PUMP/SYSTEM RELAY CONTROL CIRCUIT

TARGET IDLE NOT REACHED

NO 5 VOLTS TO MAP SENSOR

NO CHANGE IN MAP FROM START TO RUN

AUTO SHUTDOWN RELAY CONTROL CIRCUIT

NO ASD RELAY OUTPUT VOLTAGE AT PCM

INTERMITTENT LOSS OF CMP OR CKP

MISFIRE ADAPTIVE NUMERATOR AT LIMIT

EVAP LEAK MONITOR PINCHED HOSE FOUND

P1492 ⁽²⁾

AMBIENT/BATT TEMP SEN VOLTAGE TOO HIGH

P1493 ⁽²⁾

AMBIENT/BATT TEMP SEN VOLTAGE TOO LOW

LEAK DETECTION PUMP SW OR MECHANICAL FAULT

LEAK DETECTION PUMP SOLENOID CIRCUIT

P1594 ⁽²⁾

CHARGING SYSTEM VOLTAGE TOO HIGH

P1595 ⁽⁴⁾

SPEED CONTROL SOLENOID CIRCUITS

P1596 ⁽⁴⁾

SPEED CONTROL SWITCH ALWAYS HIGH

P1597 ⁽⁴⁾

SPEED CONTROL SWITCH ALWAYS LOW

P1682 ⁽²⁾

CHARGING SYSTEM VOLTAGE TOO LOW

P1683 ⁽⁴⁾

SPD CTRL PWR RELAY; OR S/C 12V DRIVER CKT

WRONG OR INVALID KEY MSG RECEIVED FROM SKIM

NO SKIM BUS MESSAGE RECEIVED

NO CLUSTER BUS MESSAGE

PCM FAILURE EEPROM WRITE DENIED

P/N SWITCH PERFORMANCE

⁽¹⁾	Perform appropriate DTC test under DIAGNOSTIC TESTS.

⁽²⁾	This DTC is related to charging system. For diagnostic procedure, see appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS.

⁽³⁾	This DTC is related to automatic transmission diagnostics. For diagnostic procedure, see appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS.

⁽⁴⁾	This DTC is related to cruise control system diagnostics. For diagnostic procedure, see appropriate CRUISE CONTROL SYSTEMS article in ACCESSORIES & EQUIPMENT.