GM Service Manual Online
For 1990-2009 cars only

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

Removal Procedure

    Important: 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%. 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.

  1. Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life.
  2. Notice: In order to prevent internal damage to the PCM, the ignition must be OFF when disconnecting or reconnecting the PCM connector.

    Important: 

       • To prevent internal PCM damage, the ignition must be OFF when disconnecting or reconnecting power to the PCM. For example, when working with a battery cable, PCM pigtail, PCM fuse, or jumper cables.
       • Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM module connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the PCM.


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


    Object Number: 1352004  Size: SH
  5. Disengage the PCM bracket mounting tabs, while removing the PCM.

Installation Procedure


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

  2. Object Number: 1350711  Size: SH
  3. Connect the PCM harness connectors (2) to the PCM body (3).
  4. If a new PCM is being installed, the PCM must be programmed. Refer to Service Programming System (SPS) in Programming.
  5. Perform the crankshaft position (CKP) system variation learn procedure. Refer to Crankshaft Position System Variation Learn or to Crankshaft Position System Variation Learn .