GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1998 🢒 Skylark 🢒 Engine 🢒 Engine Controls - 2.4L 🢒 Powertrain Control Module Replacement

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

Service of the PCM should normally consist of either replacement of the PCM or EEPROM re-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. DTC P0601 indicates the EEPROM programming has malfunctioned. When DTC P0601 is obtained, re-program the EEPROM.

The ignition should be OFF for at least 10 seconds before disconnecting power to the PCM so the IAC valve has time to move to the engine OFF position.

Removal Procedure

Important: Turn the ignition switch OFF to prevent internal PCM damage when disconnecting or reconnecting power to the PCM (for example, battery cable, PCM pigtail, PCM fuse, jumper cables, etc.). The ignition switch should be OFF for at least 10 seconds before disconnecting power to the PCM so the IAC valve has time to move to the engine OFF position.


    Object Number: 51607 Size: SH
  1. Disconnect the negative battery cable.

    2. 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.

  2. Remove the RH hush panel.
  3. Loosen the PCM electrical connectors screws (2).

    4. Notice: Do not touch the PCM connector pins or soldered components on the circuit board in order to prevent possible electrostatic discharge (ESD) damage. Do not remove the integrated circuit boards from the carrier.

  4. Disconnect the PCM electrical connectors (3).

    5. Important: PCM removal is eased when the glove box door is opened.

  5. Remove the PCM mounting bolts (1).
  6. Remove the retainer from the PCM.
  7. Slide the PCM (4) and retainer from the PCM bracket.

Installation Procedure

Remove the new PCM from its packaging and check the service number to make sure it is the same number or updated number as the malfunctioning PCM.


    Object Number: 51607 Size: SH
  1. Slide the PCM (4) into the PCM retainer.
  2. Install the PCM mounting bolts (1).

    3. Tighten
    PCM mounting bolt to 2 N·m (18 lb. in.).

    Notice: Do not touch the PCM connector pins or soldered components on the circuit board in order to prevent possible electrostatic discharge (ESD) damage. Do not remove the integrated circuit boards from the carrier.

  3. Install the PCM electrical connectors (3).
  4. Tighten the PCM connector screws (2).
  5. Install the RH hush panel.
  6. Connect the negative battery cable.
  7. Reprogram the PCM and perform the Crankshaft Position System Variation Learning Procedure.