GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Notice: Check the resistance values of all PCM relays, solenoids, and other output controls before replacing or substituting the Powertrain Control Module (PCM). Check all the sensor wiring and the PCM output control circuits for a short to ground before replacing or substituting the PCM. Perform all circuit repairs or malfunctioning component part replacements before installing a replacement or substitute PCM. This will prevent damage to the replacement or substitute PCM.

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.

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: The replacement PCM must be programmed.


    Object Number: 674015  Size: SH

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the negative battery cable.
  2. Disable the SIR system. Refer to SIR Disabling and Enabling in SIR.
  3. Release the two plastic retainers (2) with the blade of a screwdriver and remove the PCM cover (1).

  4. Object Number: 466479  Size: SH
  5. Disconnect the four PCM electrical connectors.
  6. Remove the two PCM retaining bolts (3).
  7. Slide the PCM (4) forward and out from the PCM bracket.
  8. Remove the four PCM bracket bolts (1).
  9. Remove the PCM bracket (2) from underneath the instrument panel.

Installation Procedure


    Object Number: 466479  Size: SH
  1. Install the PCM bracket (2) underneath the instrument panel.
  2. 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.

  3. Secure the PCM bracket (2) with the 4 bolts (1).
  4. Tighten
    Tighten the PCM bracket bolts to 10 N·m (89 lb in).

  5. Install the PCM (4) into the PCM bracket (2).
  6. Secure the PCM to the PCM bracket with the 2 bolts.
  7. Tighten
    Tighten the PCM retaining bolts to 10 N·m (89 lb in).

  8. Connect the four PCM electrical connectors.

  9. Object Number: 466478  Size: SH
  10. Install the PCM cover (1) and secure with the two plastic retainers.
  11. Enable the SIR system. Refer to SIR Disabling and Enabling .
  12. Connect the negative battery cable.
  13. Program the PCM before starting the engine and operating the vehicle. Refer to Powertrain Control Module Programming .