GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2006 🢒 Pursuit 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 Engine Control Module Replacement

Notice: 

   • Turn the ignition OFF when installing or removing the control module connectors and disconnecting or reconnecting the power to the control module (battery cable, powertrain control module (PCM)/engine control module (ECM)/transaxle control module (TCM) pigtail, control module fuse, jumper cables, etc.) in order to prevent internal control module damage.
   • Control module damage may result when the metal case contacts battery voltage. DO NOT contact the control module metal case with battery voltage when servicing a control module, using battery booster cables, or when charging the vehicle battery.
   • In order to prevent any possible electrostatic discharge damage to the control module, do no touch the connector pins or the soldered components on the circuit board.
   • Remove any debris from around the control module connector surfaces before servicing the control module. Inspect the control module connector gaskets when diagnosing or replacing the control module. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the control module.
   • The replacement control module must be programmed.

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 5 000 km (3,000 mi) from the last engine oil change.

Removal Procedure
  1. Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life.
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.

    3. Object Number: 873343 Size: SH
  3. Disconnect the small engine control module (ECM) harness connector (3) from the ECM.
  4. Remove the bolt retaining the large ECM connector to the ECM.
  5. Disconnect the large ECM harness connector (4) from the ECM.

    6. Object Number: 857196 Size: SH

    Notice: Control module damage may result when the metal case contacts battery voltage. DO NOT contact the control module metal case with battery voltage when servicing a control module, using battery booster cables or when charging the vehicles battery.

  6. Use the retaining tab to release the ECM from the underhood junction block bracket.

Installation Procedure

    Object Number: 857196 Size: SH

    Notice: Control module damage may result when the metal case contacts battery voltage. DO NOT contact the control module metal case with battery voltage when servicing a control module, using battery booster cables or when charging the vehicles battery.

  1. Use the retaining tab to secure the ECM, when installing the ECM to the underhood junction block bracket.

    2. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 873343 Size: SH
  2. Connect the large ECM harness connector (4) to the ECM.

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

  3. Connect the small ECM harness connector (3) to the ECM.
  4. Connect the negative Battery Cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  5. Program the ECM. Refer to Control Module References in Computer/Integrating Systems.