GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

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

    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 percent. 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. Object Number: 1285259  Size: SH
  3. Turn the ignition OFF.
  4. Important: Ensure that there is no main relay circuit voltage (ECM Fuse).

  5. Use a DVOM in order to measure the main relay circuit voltage at the engine control module (ECM) fuse in the underhood fuse block. Refer to Electrical Center Identification Views in Wiring Systems.
  6. Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  7. Remove the ECM fuse in the underhood fuse block. Refer to Electrical Center Identification Views in Wiring Systems.
  8. Remove the transmission control module/instrument panel cluster (TCM/IPCM) fuse in the underhood fuse block. Refer to Electrical Center Identification Views in Wiring Systems.
  9. Remove the ECM/TCM fuse in the underhood fuse block. Refer to Electrical Center Identification Views in Wiring Systems.
  10. Unlock the body side (outboard) ECM electrical connector.
  11. 8.1. Depress the ECM electrical connector lever lock (1).
    8.2. Simultaneously rotate the ECM connector clamp lever and depress the lock slide (2).

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


    Object Number: 1394047  Size: SH
  12. Remove the body side (outboard) ECM connector.

  13. Object Number: 1394046  Size: SH
  14. Unlock and remove the engine side (inboard) ECM connector.

  15. Object Number: 1394045  Size: SH
  16. Remove the ECM redundant ground wire and bolt from the ECM.

  17. Object Number: 1394049  Size: SH
  18. Remove the ECM bolts.
  19. Remove the ECM.

  20. Object Number: 1394048  Size: SH
  21. If necessary, perform the following steps:
  22. 14.1. Remove the ECM bracket bolts.
    14.2. Remove the ECM bracket.

Installation Procedure


    Object Number: 1394048  Size: SH
  1. Install the ECM bracket, as necessary.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the ECM bracket bolts.
  4. Tighten
    Tighten the ECM bracket bolts to 10 N·m (89 lb in).


    Object Number: 1394049  Size: SH

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

  5. Install the ECM.
  6. Install the ECM bolts.
  7. Tighten
    Tighten the ECM bolts to 10 N·m (89 lb in).


    Object Number: 1394045  Size: SH
  8. Install the ECM redundant ground and bolt to the ECM.
  9. Tighten
    Tighten the ECM redundant ground wire bolt to 5 N·m (44 lb in).


    Object Number: 1394046  Size: SH
  10. Install the engine side (inboard) ECM connector.

  11. Object Number: 1394047  Size: SH
  12. Install the body side (outboard) ECM connector.
  13. Install the ECM/TCM fuse in the underhood fuse block. Refer to Electrical Center Identification Views in Wiring Systems.
  14. Install the TCM/IPC fuse in the underhood fuse block. Refer to Electrical Center Identification Views in Wiring Systems.
  15. Install the ECM fuse in the underhood fuse block. Refer to Electrical Center Identification Views in Wiring Systems.
  16. Connect the battery negative cable to the battery. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  17. Program the ECM. Refer to Service Programming System (SPS) in Programming and Setup.
  18. Turn OFF the ignition for at least 5 seconds after the programming event is complete.
  19. Perform the idle learn procedure. Refer to Idle Learn .
  20. Use the scan tool to clear all DTCs.