GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2001 🢒 Catera 🢒 Body and Accessories 🢒 Cruise Control 🢒 Engine Control Module Replacement

Removal Procedure

    Notice: Always turn the ignition off when installing or removing the ECM connectors in order to prevent damage to the components.

  1. Turn OFF the ignition.
  2. Remove the under hood fuse/relay cover.

    3. Object Number: 481021 Size: SH

    Notice: In order to prevent any possible electrostatic discharge damage to the ECM, do not touch the connector pins.

  3. Grasp the ECM (2) and slide the unit straight up and out of the underhood relay center.
  4. Flip the release lever and disconnect the ECM connectors (1, 3) from the ECM.
  5. Remove the fastener retaining the ECM ground wire to the ECM.
  6. Remove the fasteners that retain the ECM to the backing plate.
  7. Remove the ECM from the backing plate.

Installation Procedure

  1. The ignition must be OFF.

    2. Object Number: 481021 Size: SH

    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.

  2. Install the ECM (2) to the backing plate with the ECM mounting nuts.

    3. Tighten
    Tighten the nuts to 4 N·m (35 lb in).

  3. Install the ECM ground wire screw.

    4. Tighten
    Tighten the screw to 4 N·m (35 lb in).

  4. Carefully align the harness connector with the ECM connector.
  5. Guide the connector into place while moving the release lever to the locked position.
  6. Align the backing plate of the ECM with the slots in the relay center and slide the unit into the underhood relay center.
  7. Program the frequency code of the new ECM with the frequency of the theft deterrent module using the following procedure:
    8. 7.1. Connect the scan tool to the vehicle.
    7.2. Turn ON the ignition, with the engine OFF.
    7.3. Select Service Programming on the scan tool.
    7.4. Program the vehicle configuration as required.
    7.5. Follow the instruction on the scan tool to request the information from the controller.
    7.6. Remove the scan tool from the vehicle.
    7.7. Connect the scan tool to the Techline terminal.
    7.8. Follow the instructions on the Techline terminal to perform the vehicle theft deterrent learn function using the Service Programming System.
    7.9. Turn OFF the scan tool.
    7.10. Disconnect the scan tool from the Techline terminal.
    7.11. Reconnect the scan tool to the vehicle.
    7.12. Turn ON the ignition, with the engine OFF.
    7.13. Return to the Service Programming menu and follow the instructions to program the frequency code.
    7.14. After the programming is complete, clear any DTCs that may have set in the ECM prior to learning the correct theft frequency code.
  8. Perform the idle learn procedure. Refer to Idle Learn .
  9. Install the under hood fuse/relay cover.