GM Service Manual Online
For 1990-2009 cars only

Service of the PCM should normally consist of either replacement of the PCM or EEPROM programming. If the diagnostic procedures call for the PCM to be replaced, the PCM should be checked first to see if it is the correct part. If it is, remove the faulty PCM and install the new service PCM.

THE SERVICE PCM EEPROM WILL NOT BE PROGRAMMED. DTC P0601 and P0602 indicates the EEPROM is not programmed or has malfunctioned.

Important:: The following must be performed anytime the PCM is replaced:

  1. Program the PCM
  2. The Idle Learn Procedure
  3. The CKP System Variation Learn Procedure
  4. The Engine Oil Life Reset Procedure
  5. The Functional Check
The following must be performed anytime the PCM is disconnected, reprogrammed or loses power:

  1. The Idle Learn Procedure
  2. The Functional Check

Notice: Turn the ignition OFF when installing or removing the PCM connectors and disconnecting or reconnecting the power to the PCM (battery cable, PCM pigtail, PCM fuse, jumper cables, etc.) in order to prevent internal PCM damage.

Important: Ensure that the hood is free of contaminates (moisture) before servicing the PCM. The moisture flows into the PCM connector body when the PCM is disconnected and the hood is opened.

Removal Procedure

Important: Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM module connector gaskets when diagnosing/replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM.

    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: 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.


    Object Number: 416074  Size: SH
  3. Disconnect the PCM connectors.

  4. Object Number: 187250  Size: SH
  5. Remove the mounting fasteners from the PCM bracket.

  6. Object Number: 415726  Size: SH
  7. Remove the PCM and mounting bracket assembly from the engine compartment.
  8. Remove the PCM (1) from the mounting bracket (2).

Installation Procedure

    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.


    Object Number: 415726  Size: SH
  1. Install the PCM (1) to the mounting bracket (2).

  2. Object Number: 187250  Size: SH
  3. Install the PCM and mounting bracket assembly into the vehicle.
  4. Tighten
    Tighten the mounting bracket fasteners to 7 N·m(62 lb in).


    Object Number: 416074  Size: SH
  5. Reconnect the PCM connectors.
  6. Tighten
    Tighten the PCM connector end fasteners to 8 N·m (70 lb in).

  7. If a new PCM is being installed, program the PCM.

PCM Programming

  1. Ensure the following conditions have been met:
  2. • The battery is fully charged.
    • The ignition is ON.
    • The cable connection at the Data Link Connector (DLC) is secure.
  3. Program the PCM using the latest software matching the vehicle. Refer to Techline terminal/equipment users instructions.
  4. 2.1.  If the PCM fails to program, proceed as follows:
       • Ensure that all PCM connections are OK.
       • Check the Techline terminal/equipment for the latest software version.
       • Attempt to program the PCM. If the PCM still cannot be programmed properly, replace the PCM. The replacement PCM must be programmed.
    2.2. Program the replacement PCM.
  5. Perform the CKP System Variation Learn Procedure if a new PCM is installed. Refer to Crankshaft Position System Variation Learn .
  6. Perform the Idle Learn Procedure. Refer to PCM Idle Learn Procedure .

Functional Check

  1. Clear the Diagnostic Trouble Codes (DTCs).
  2. Perform the On-Board Diagnostic System Check.
  3. Start the engine and idle for one minute.
  4. Scan for DTCs using the scan tool.