GM Service Manual Online
For 1990-2009 cars only

Powertrain Control Module Diagnosis General Information

The approved procedure for diagnosing all powertrain control system malfunctions is included in the Strategy Based Diagnostic Flow . The preliminary checks and the Powertrain On-Board Diagnostic System Check must be performed to successfully diagnose and repair the powertrain systems.

To read and clear diagnostic trouble codes, use a scan tool.

Important: Use a scan tool to clear diagnostic trouble codes from the PCM memory. Diagnostic trouble codes can also be cleared by turning OFF the ignition and disconnecting the battery power from the PCM for 30 seconds, but this method will also cause all diagnostic information in the PCM memory to be cleared and all the diagnostic tests will have to be re-run.

Since the PCM can have a failure which may affect only one circuit, following the approved diagnostic procedures will determine which circuit has a problem and where it is. If a diagnostic table indicates that the PCM connections or PCM is the cause of a problem and the PCM is replaced, but does not correct the problem, one of the following conditions may exist:

    • There is a problem with the PCM terminal connections. The diagnostic table will indicate that the PCM connections or PCM is the problem. The terminals may have to be removed from the PCM connector in order to check them properly.
    • The EEPROM program is not correct for the application.
    •  Incorrect components may cause a malfunction and may or may not set a DTC.
    • The problem is intermittent. This means that the problem is not present at the time the system is being checked. In this case, refer to the Symptoms portion of the manual and make a careful visual and physical inspection of all suspected components and wiring associated with the affected system.
    • Shorted solenoid, relay coil, or harness. Solenoids and relays are turned ON and OFF by the PCM using internal electronic switches called drivers. Each driver is part of a group of seven called output driver modules. A shorted solenoid, relay coil, or harness will not damage the PCM but will cause the solenoid or relay to be inoperative. The J 34636 tester, or equivalent, provides a fast, accurate means of checking for a shorted coil or a short to battery voltage.

Powertrain Control Module Diagnosis Powertrain DTCs

PCM Diagnostic Trouble Codes

DTC Description

Type

Illuminate MIL

DTC P0101 Mass Air Flow (MAF) Sensor Performance

A

Yes

DTC P0102 Mass Air Flow (MAF) Sensor Circuit Low Frequency

A

Yes

DTC P0103 Mass Air Flow (MAF) Sensor Circuit High Frequency

A

Yes

DTC P0107 Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage

B

Yes

DTC P0108 Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage

B

Yes

DTC P0112 Intake Air Temperature (IAT) Sensor Circuit Low Voltage

B

Yes

DTC P0113 Intake Air Temperature (IAT) Sensor Circuit High Voltage

B

Yes

DTC P0117 Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage

B

Yes

DTC P0118 Engine Coolant Temperature (ECT) Sensor Circuit High Voltage

B

Yes

DTC P0121 Throttle Position (TP) Sensor Performance

A

Yes

DTC P0122 Throttle Position (TP) Sensor Circuit Low Voltage

A

Yes

DTC P0123 Throttle Position (TP) Sensor Circuit High Voltage

A

Yes

DTC P0125 Engine Coolant Temperature (ECT) Insufficient for Closed Loop Fuel Control

B

Yes

DTC P0131 HO2S Circuit Low Voltage Sensor 1

B

Yes

DTC P0132 HO2S Circuit High Voltage Sensor 1

B

Yes

DTC P0133 HO2S Slow Response Sensor 1

B

Yes

DTC P0134 HO2S Circuit Insufficient Activity Sensor 1

B

Yes

DTC P0135 HO2S Heater Performance Sensor 1

B

Yes

DTC P0137 HO2S Circuit Low Voltage Sensor 2

B

Yes

DTC P0138 HO2S Circuit High Voltage Sensor 2

B

Yes

DTC P0140 HO2S Circuit Insufficient Activity Sensor 2

B

Yes

DTC P0141 HO2S Heater Performance Sensor 2

B

Yes

DTC P0171 Fuel Trim System Lean

B

Yes

DTC P0172 Fuel Trim System Rich

B

Yes

DTC P0218 Transaxle Over Temperature Condition (Refer To 4T60-E Transaxle Diagnosis / 4T65-E Automatic Transaxle Diagnosis )

D

No

DTC P0300 Engine Misfire Detected

B

Yes

DTC P0325 Knock Sensor Module Performance

D

No

DTC P0326 Knock Sensor Noise Channel High Voltage

D

No

DTC P0327 Knock Sensor (KS) Circuit

D

No

DTC P0336 Crankshaft Position (CKP) Sensor Circuit

B

Yes

DTC P0341 Camshaft Position (CMP) Sensor Performance

B

Yes

DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient

A

Yes

DTC P0420 Catalyst System Low Efficiency

A

Yes

DTC P0440 Evaporative Emission (EVAP) System

A

Yes

DTC P0441 Evaporative Emission (EVAP) System No Flow During Purge

B

Yes

DTC P0442 Evaporative Emission (EVAP) System Small Leak Detected

A

Yes

DTC P0446 Evaporative Emission (EVAP) Vent System Performance

A

Yes

DTC P0502 Vehicle Speed Sensor Circuit - Low Input (Refer To 4T60-E Automatic Transaxle Diagnosis )

A

Yes

DTC P0502 Vehicle Speed Sensor Circuit - Low Input (Refer To 4T65-E Automatic Transaxle Diagnosis )

B

Yes

DTC P0503 Vehicle Speed Sensor Circuit - Intermittent Input (Refer To 4T60-E Automatic Transaxle Diagnosis )

A

Yes

DTC P0503 Vehicle Speed Sensor Circuit - Intermittent Input (Refer To 4T65-E Automatic Transaxle Diagnosis )

B

Yes

DTC P0506 Idle Speed Low

B

Yes

DTC P0507 Idle Speed High

B

Yes

DTC P0530 Air Conditioning (A/C) Refrigerant Pressure Sensor Circuit

D

No

DTC P0560 System Voltage

D

No

DTC P0601 Control Module Read Only Memory (ROM)

B

Yes

DTC P0602 Control Module Not Programmed

B

Yes

DTC P0705 Trans Range Switch Circuit

D

No

DTC P0706 Trans Range Switch Performance

D

No

DTC P0711 Transaxle Fluid Temperature Sensor Circuit Range/Performance (Refer to 4T60-E Automatic Transaxle Diagnosis / 4T65-E Automatic Transaxle Diagnosis )

B

Yes

DTC P0712 Transaxle Fluid Temperature (TFT) Sensor Circuit - Low Signal Voltage (Refer To 4T60-E Automatic Transaxle Diagnosis / 4T65-E Automatic Transaxle Diagnosis )

D

No

DTC P0713 Transaxle Fluid Temperature (TFT) Sensor Circuit - High Signal Voltage (Refer To 4T60-E Automatic Transaxle Diagnosis / 4T65-E Automatic Transaxle Diagnosis )

D

No

DTC P0716 Input Speed Sensor Circuit Range/Performance (Refer to 4T65-E Automatic Transaxle Diagnosis )

B

Yes

DTC P0717 Input Speed Sensor Circuit No Signal (Refer to 4T65-E Automatic Transaxle Diagnosis )

B

Yes

DTC P0719 Brake Switch Circuit Low (Refer To 4T60-E Automatic Transaxle Diagnosis / 4T65-E Automatic Transaxle Diagnosis )

D

No

DTC P0724 Brake Switch Circuit High (Refer To 4T60-E Automatic Transaxle Diagnosis / 4T65-E Automatic Transaxle Diagnosis )

D

No

DTC P0730 Undefined Gear Ratio (Refer To 4T65-E Automatic Transaxle Diagnosis )

D

No

DTC P0740 TCC Enable Solenoid Circuit (Refer To 4T60-E Transaxle Diagnosis )

A

Yes

DTC P0741 Torque Converter Clutch Circuit Stuck Off (Refer To 4T65-E Automatic Transaxle Diagnosis )

B

Yes

DTC P0742 Torque Converter Clutch Circuit Stuck On (Refer To 4T60-E Automatic Transaxle Diagnosis )

B

Yes

DTC P0742 Torque Converter Clutch Circuit Stuck On (Refer To 4T65-E Automatic Transaxle Diagnosis )

A

Yes

DTC P0748 Pressure Control Solenoid Electrical (Refer To 4T65-E Automatic Transaxle Diagnosis )

D

No

DTC P0751 Shift Solenoid 1 - Performance/Stuck Off (Refer To 4T60-E Automatic Transaxle Diagnosis )

A

Yes

DTC P0751 1-2 Shift Solenoid Performance (Refer To 4T65-E Automatic Transaxle Diagnosis )

B

Yes

DTC P0753 Shift Solenoid 1 - Electrical (Refer To 4T60-E Automatic Transaxle Diagnosis )

A

Yes

DTC P0753 1-2 Shift Solenoid Electrical (Refer To 4T65-E Automatic Transaxle Diagnosis )

A

Yes

DTC P0756 Shift Solenoid 2 - Performance/Stuck Off (Refer To 4T60-E Automatic Transaxle Diagnosis )

A

Yes

DTC P0756 2-3 Shift Solenoid Performance (Refer To 4T65-E Automatic Transaxle Diagnosis )

A

Yes

DTC P0758 Shift Solenoid 2 - Electrical (Refer To 4T60-E Automatic Transaxle Diagnosis )

A

Yes

DTC P0758 2-3 Shift Solenoid Electrical (Refer To 4T65-E Automatic Transaxle Diagnosis )

A

Yes

DTC P1106 Manifold Absolute Pressure (MAP) Sensor Circuit Intermittent High Voltage

D

No

DTC P1107 Manifold Absolute Pressure (MAP) Sensor Circuit Intermittent Low Voltage

D

No

DTC P1111 Intake Air Temperature (IAT) Sensor Circuit Intermittent High Voltage

D

No

DTC P1112 Intake Air Temperature (IAT) Sensor Circuit Intermittent Low Voltage

D

No

DTC P1114 Engine Coolant Temperature (ECT) Sensor Circuit Intermittent Low Voltage

D

No

DTC P1115 Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage

D

No

DTC P1121 Throttle Position (TP) Sensor Circuit Intermittent High Voltage

D

No

DTC P1122 Throttle Position (TP) Sensor Circuit Intermittent Low Voltage

D

No

DTC P1133 HO2S Insufficient Switching Sensor 1

B

Yes

DTC P1134 HO2S Transition Time Ratio Sensor 1

B

Yes

DTC P1200 Injector Control Circuit

B

Yes

DTC P1257 Supercharger Engine Overboost

D

No

DTC P1336 Crankshaft Position (CKP) System Variation Not Learned

A

Yes

DTC P1350 Bypass Line Monitor

B

Yes

DTC P1361 Ignition Control (IC) Circuit Low Voltage

B

Yes

DTC P1374 Crankshaft Position (CKP) High to Low Resolution Frequency Correlation

B

Yes

DTC P1380 Misfire Detected - Rough Road Data Not Available

D

No

DTC P1406 Exhaust Gas Recirculation (EGR) Position Sensor Performance

B

Yes

DTC P1441 Evaporative Emission (EVAP) System Flow During Non-Purge

B

Yes

DTC P1441 Evaporative Emission (EVAP) System Flow During Non-Purge

A

Yes

DTC P1520 Park/Neutral Position (PNP) Switch Circuit

D

No

DTC P1554 Cruise Control Feedback Circuit

D

No

DTC P1571 Traction Control Torque Request Circuit

D

No

DTC P1573 Lost Communications with Brake/Traction Control (EBTCM) System

D

No

DTC P1619 Engine Oil Life Monitor Reset Switch Circuit

D

No

DTC P1626 Theft Deterrent Fuel Enable Signal Lost

D

No

DTC P1629 Theft Deterrent Fuel Enable Signal Not Received

D

No

DTC P1635 5 Volt Reference Circuit

B

Yes

DTC P1639 5 Volt Reference 2 Circuit

D

No

DTC P1641 Malfunction Indicator Lamp (MIL) Control Circuit

D

No

DTC P1643 Fuel Pump Speed Output Circuit

D

No

DTC P1645 Supercharger Boost Solenoid Control Control Circuit

D

No

DTC P1651 Cooling Fan Relay 1 Control Circuit

B

Yes

DTC P1652 Cooling Fan Relay 2 Control Circuit

B

Yes

DTC P1653 Traction Control Delivered Torque Output Circuit

D

No

DTC P1654 Air Conditioning (A/C) Clutch Relay Control Circuit

D

No

DTC P1655 Evaporative Emission (EVAP) Purge Solenoid Control Circuit

B

Yes

DTC P1662 Cruise Control Inhibit Output Circuit

D

No

DTC P1663 Charging System Lamp Control Circuit

D

No

DTC P1673 Engine Coolant Temperature Lamp Control Circuit

D

No

DTC P1675 Evaporative Emission (EVAP) Vent Solenoid Control Circuit

B

Yes

DTC P1810 Transaxle Fluid Pressure Switch Malfunction (Refer To 4T65-E Transaxle Diagnosis )

B

Yes

DTC P1811 Maximum Adapt and Long Shift (Refer To 4T65-E Transaxle Diagnosis )

D

No

DTC P1860 Torque Converter Clutch PWM Solenoid Circuit (Refer To 4T60-E Transaxle Diagnosis / 4T65-E Transaxle Diagnosis )

A

Yes

DTC P1870 Transaxle Component Slipping (Refer To 4T60-E Transaxle Diagnosis )

B

Yes

DTC P1887 TCC Release Switch Circuit Malfunction (Refer To 4T65-E Transaxle Diagnosis )

B

Yes