Engine Control Module Replacement

Fig 1: Engine Control Module & Mounting Components

Courtesy of GENERAL MOTORS COMPANY

Callout	Component Name
NOTE: If the ECM is to be replaced, the ECM must be RESET (prepared for removal) prior to removal from the vehicle. Failing to reset the ECM will result in the following: Inability to test the ECM for warranty purposes Inability to use the ECM in other vehicles. Preliminary Procedures Prepare the ECM for replacement. Refer to Control Module References . Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life. Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection .
1	Engine Control Module Mounting Bracket Procedure Disconnect the electrical wiring harness connectors from the engine control module. Unclip the engine control module bracket from the battery tray.
2	Engine Control Module Fasteners (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten 10 N.m (89 lb in)
3	Engine Control Module CAUTION: 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. Procedure Remove the engine control module from the engine control module bracket. If replacing the ECM, refer to Control Module References for programming and setup. NOTE: Before removing the engine control module (ECM), record the oil life percentage remaining. Use the scan tool to reset the Engine Oil Life remaining back to the original percentage recorded.