Engine Control Module: Service and Repair

Engine Control Module Replacement

Service of the engine control module (ECM) should normally consist of either replacement of the ECM or electrically erasable programmable read only memory (EEPROM) programming. If the diagnostic procedures call for the ECM to be replaced, the ECM should be inspected first to see if the correct part is being used. If the correct part is being used, remove the faulty ECM and install the new service ECM.

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.

Note: Record the current engine oil life percentage and use a scan tool to update the NEW ECM, if replacing.

Removal Procedure




1. Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life.
2. Remove the windshield washer solvent container. Refer to Windshield Washer Solvent Container Replacement (Service and Repair).
3. Disengage the integral connector position assurance (CPA) retainer (1) on the body wiring harness electrical connector.
4. Disconnect the body wiring harness electrical connector (2) from the ECM.




5. Disengage the integral CPA retainers on the engine wiring harness electrical connectors.
6. Disconnect the engine wiring harness electrical connectors (2) from the ECM.




7. Lift up the ECM bracket tabs (2) and tilt the ECM (1) towards the front of the vehicle, removing the ECM (1).

Installation Procedure




1. Set the bottom of the ECM (1) into the bracket, and push the top of the ECM against the bracket. Ensure that the tabs (2) secure the ECM (1).




2. Connect the engine wiring harness electrical connectors (2) to the ECM.
3. Engage the integral CPA retainers on the engine wiring harness electrical connectors.




4. Connect the body wiring harness electrical connector (2) to the ECM.
5. Engage the integral CPA retainer (1) on the body wiring harness electrical connector.
6. If a NEW ECM was installed, the ECM must be programmed. Refer to Control Module References (Programming and Relearning).
7. Install the windshield washer solvent container. Refer to Windshield Washer Solvent Container Replacement (Service and Repair).