GM Service Manual Online
For 1990-2009 cars only

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

Important: 

   • To prevent internal PCM damage, the ignition switch must be OFF when disconnecting or reconnecting power to the PCM.
   • Remove any debris from around 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.
   • The replacement PCM must be reprogrammed.

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. Object Number: 814118  Size: SH
  3. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  4. Release the PCM cover mounting tabs.
  5. Remove the PCM cover from the mounting brackets.
  6. Remove the PCM cover.

  7. Object Number: 814117  Size: SH
  8. Loosen the PCM electrical connector bolts (2).
  9. 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.

    Notice: In order to prevent internal damage to the PCM, the ignition must be OFF when disconnecting or reconnecting the PCM connector.

  10. Disconnect the PCM electrical connectors.

  11. Object Number: 814119  Size: SH
  12. Release the spring latch from the PCM.
  13. Release the PCM mounting tabs from the PCM.
  14. Remove the PCM.

Installation Procedure


    Object Number: 814119  Size: SH
  1. Install the PCM.
  2. Ensure that the mounting tabs are engaged.

  3. Secure the spring latch to the PCM.
  4. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 814117  Size: SH
  5. Connect the PCM electrical connectors.
  6. Tighten the PCM electrical connector bolts (2).
  7. Tighten
    Tighten the bolts to 8 N·m (71 lb in).


    Object Number: 814118  Size: SH
  8. Install the PCM cover.
  9. Ensure the mounting tabs are engaged into the mounting holes in the cover.

  10. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  11. If a NEW PCM was installed, program the PCM. Refer to Service Programming System (SPS) in Programming.