Engine Control Module: Service and Repair

Engine Control Module Replacement

Removal Procedure

Service of the engine control module (ECM) should consist of either replacement of the ECM or programming of the electrically erasable programmable read only memory (EEPROM). If the diagnostic procedures call for the ECM to be replaced, the replacement ECM should be checked to ensure that 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.




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 (Battery Negative Cable Disconnection and Connection).
3. Disconnect the engine wiring harness electrical connectors (2) from the ECM (1).




4. Release the ECM bracket tabs (3).
5. Remove the ECM (4) from the bracket (2).

Installation Procedure




1. Install the ECM (4) to the bracket (2).
2. Ensure that the ECM bracket tabs (3) fully engage the ECM.




3. Connect the engine wiring harness electrical connectors (2) to the ECM (1).
4. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection (Battery Negative Cable Disconnection and Connection).
5. If a new ECM was installed, program the ECM. Refer to Control Module References (Programming and Relearning).
6. Using a scan tool, set the remaining engine oil life.