GM Service Manual Online
For 1990-2009 cars only

Service of the engine control module (ECM) should normally consist of either replacement of the ECM or electrically erasable programmable read only memory (EEPROM) programming. If the diagnostic procedures call for the ECM to be replaced, the ECM should be inspected first to see if the correct part is being used. If the correct part is being used, remove the faulty ECM and install the new service ECM.

Warning: Replacement or reprogramming of the ECM, or replacement of the clutch pedal position sensor (CPPS) or clutch pedal requires that a CPPS learn procedure be performed. Failure to perform the CPPS learn procedure may result in personal injury or damage to the vehicle or its components if the vehicle is in gear and the starter motor is accidentally engaged.

Caution: 

   • Turn the ignition OFF when installing or removing the control module connectors and disconnecting or reconnecting the power to the control module (battery cable, powertrain control module (PCM)/engine control module (ECM)/transaxle control module (TCM) pigtail, control module fuse, jumper cables, etc.) in order to prevent internal control module damage.
   • Control module damage may result when the metal case contacts battery voltage. DO NOT contact the control module metal case with battery voltage when servicing a control module, using battery booster cables, or when charging the vehicle battery.
   • In order to prevent any possible electrostatic discharge damage to the control module, do no touch the connector pins or the soldered components on the circuit board.
   • Remove any debris from around the control module connector surfaces before servicing the control module. Inspect the control module connector gaskets when diagnosing or replacing the control module. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the control module.
   • The replacement control module must be programmed.

Note: It is necessary to record the remaining engine oil life. If the replacement module is not programed with the remaining engine oil life, the engine oil life will default to 100 percent. If the replacement module is not programmed with the remaining engine oil life, the engine oil will need to be changed at 5000 km (3,000 mi) from the last engine oil change.

Removal Procedure

  1. Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life.

  2. Object Number: 1350711  Size: SH
  3. Disconnect the ECM harness connectors (2) from the ECM (3).

  4. Object Number: 1352004  Size: SH

    Caution: Do not touch the connector pins or soldered components on the circuit board in order to prevent possible electrostatic discharge (ESD) damage to the PCM.

  5. Disengage the ECM bracket mounting tabs, while removing the ECM.

Installation Procedure


    Object Number: 1352004  Size: SH
  1. Install the ECM into the ECM mounting bracket, allowing the tabs to fully engage.

  2. Object Number: 1350711  Size: SH
  3. Connect the ECM harness connectors (2) to the ECM body (3).
  4. If a new ECM is being installed, the ECM must be programmed. Refer to Control Module References.
  5. If equipped with a manual transmission, perform the clutch pedal position sensor learn procedure. Refer to Clutch Pedal Position Sensor Learn.