GM Service Manual Online
For 1990-2009 cars only

Notice: In order to prevent possible Electrostatic Discharge damage to the PCM, Do Not touch the connector pins or the soldered components on the circuit board.

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, 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 P0602 indicates the EEPROM is not programmed or has malfunctioned.

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. Caution: Before servicing any electrical component, the ignition and start switch must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.

  3. Remove the negative battery cable.
  4. Remove the engine coolant reservoir purge hose.
  5. Remove the fuse block.
  6. Remove the PCM access cover.
  7. Remove the connectors from the PCM.
  8. Remove the PCM from engine compartment.

Installation Procedure

  1. Install the PCM in the engine compartment.
  2. Install the connectors to the PCM.
  3. Install the PCM access cover.
  4. Install the fuse block.
  5. Install the engine coolant reservoir purge hose.
  6. Install the negative battery cable.

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

EEPROM Programming

  1. Set-up - Ensure that the following conditions have been met:
  2. •  The ignition is on.
    •  The Techline equipment connection at the Data Link Connector (DLC) is secure.
  3. If the PCM fails to program, check the Techline equipment for the latest software version.
  4. Attempt to program the PCM. If the PCM still cannot be programmed properly, replace the PCM. The replacement PCM must be programmed.

Functional Check

  1. Perform On-Board Diagnostic System Check.
  2. Start engine and run for one minute.
  3. Scan for DTCs using the scan tool.
  4. If DTC P0325 sets, the KS module is not fully seated, is missing, or is faulty.