GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Notice: Place the ignition switch in the LOCK position when disconnecting or reconnecting the power to the PCM in order to prevent internal PCM damage. Place the ignition switch in the LOCK position when disconnecting or reconnecting the battery cables, the PCM connectors, or the fuses. The ignition switch supplies power to the PCM in all key positions except LOCK.

    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.

    Important: It is necessary to record the remaining automatic transmission fluid life. If the replacement module is not programed with the remaining automatic transmission fluid life, the automatic transmission fluid life will default to 100%. If the replacement module is not programmed with the remaining automatic transmission fluid life, the automatic transmission fluid will need to be changed at 83000 km (50,000 mi) from the last automatic transmission fluid change.

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

  2. Object Number: 26335  Size: SH

    Important: The key must be in the LOCK position for a minimum of 30 seconds prior to disconnecting power to the PCM. This is to allow the PCM to store the Transaxle fluid life, transaxle shift adapts and Throttle Position Learned value into the EEPROM. Failure to wait the 30 seconds may result in a EEPROM reset and the Transaxle fluid life being reset to 0.

  3. Disconnect the negative battery cable.
  4. Disconnect the IAT sensor connector.
  5. Remove the gusset (brace) from between the LH fender and the radiator core support by removing the 5 attaching bolts.
  6. Loosen the Intake Air duct clamp at the MAF sensor.
  7. Remove the Intake Air duct/air cleaner assembly.
  8. Remove the air cleaner assembly.

  9. Object Number: 15061  Size: MH
  10. Lift the air inlet assembly (1) onto the radiator core support area by pulling firmly straight up.

  11. Object Number: 15063  Size: LH
  12. Open the air inlet housing (4) to gain access to the PCM (2).
  13. Loosen the connector attaching bolts.
  14. Disconnect both PCM connectors (1 and 5).
  15. • If installing a replacement PCM the KS module will have to be transferred from the original PCM to the replacement PCM. Refer to Knock Sensor (KS) Module Replacement .
    • If installing a replacement PCM the PCM Isolators (3) will have to be transferred to the replacement PCM.

Installation Procedure

If a replacement PCM is being installed it will be necessary to transfer the KS module from the original PCM. Refer to Knock Sensor (KS) Module Replacement .


    Object Number: 15063  Size: LH
  1. Slide the PCM Isolators (3) on to the PCM (2).
  2. Install the PCM connectors (1 and 5).
  3. Tighten
    Tighten the PCM connectors screws to 10 N·m (7 lb ft). Refer to

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

    in general information.

  4. Place the PCM (2) into the air inlet housing (4).
  5. Close and latch the air inlet housing (4).

  6. Object Number: 15061  Size: MH
  7. Install the air inlet housing (1) by inserting the outboard locating pin into the inside fender alignment hole.
  8. Press the air inlet housing (1) firmly down to engage the bottom locating pins.

  9. Object Number: 26335  Size: SH
  10. Ensure that the locating pin grommets are present and properly positioned in the bottom of the air cleaner assembly (1).
  11. Install the intake air duct/air cleaner assembly (1) onto the air inlet housing (2).
  12. Important: An improperly installed air cleaner or a distorted /missing Intake Air Duct may cause a DTC to set. Ensure air cleaner assembly and IA duct is installed correctly and that there are no kinks or folds in the IA Duct or possible debris in the air cleaner assembly or the MAF sensor inlet screen that may distort the air flow.

  13. Install the Intake Air duct to the MAF sensor.
  14. Tighten
    Tighten the Intake Air duct clamp to 3 N·m (27 lb in).

  15. Connect the IAT sensor connector.
  16. Install the gusset (brace) between the LH fender and the radiator core support.
  17. Tighten
    Tighten the 5 gusset (brace) attaching bolts to 24 N·m (18 lb ft).

  18. Connect the negative battery cable.
  19. Notice: The PCM will be damaged if proper programming procedures are not followed.

  20. If a replacement PCM is being installed it must be programmed (flashed) using the latest Techline programming procedures.
  21. Start the engine. If the engine fails to start verify the following:
  22. • The PCM contains the correct program
    • The PCM connectors are fully engaged into the PCM.
    • That all fuses are present and not blown.
  23. Connect a scan tool and perform the following:
  24. • Clear DTC P0603.
    • Reset Transaxle fluid life to that recorded prior to PCM removal.
    • Reset Engine oil life to that recorded prior to PCM replacement.