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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: 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. Release the ECM cover mounting holes away from the mounting tabs on the ECM mounting bracket.
3. Release the ECM cover from the mounting bracket.
4. Remove the ECM cover.





Caution: Do not touch the connector pins or soldered components on the circuit board in order to prevent possible electrostatic discharge (ESD) damage to the PCM.

Caution: In order to prevent internal damage to the PCM, the ignition must be OFF when disconnecting or reconnecting the PCM connector.

5. Loosen both ECM connector retaining bolts.
6. Disconnect the ECM harness connectors.
7. Release the spring latch from the ECM.
8. Release the ECM mounting tabs from the ECM.




9. Remove the ECM from the engine compartment.

Installation Procedure




1. Install the ECM to the ECM mounting bracket ensuring that the mounting tabs are engaged.
2. Secure the spring latch to the ECM.





Caution: Refer to Fastener Caution (Fastener Caution).

3. Connect the ECM connectors to the ECM.

Tighten the fasteners to 8 Nm (71 lb in).




4. Install the ECM cover to the ECM mounting bracket, ensuring the mounting tabs on the ECM mounting bracket are engaged into the mounting holes in the ECM cover.
5. If a new ECM is being installed, program the ECM. Refer to Control Module References (Programming and Relearning).

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