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Engine Control Module: Service and Repair



POWERTRAIN CONTROL MODULE (PCM) REPLACEMENT

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

NOTE: Turn the ignition OFF when installing or removing the PCM connectors and disconnecting or reconnecting the power to the PCM (battery cable, PCM pigtail, PCM fuse, jumper cables, etc.) in order to prevent internal PCM damage.

IMPORTANT:
- Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM module connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the PCM.
- The replacement PCM must be programmed.

Removal Procedure

1. Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life.

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.




2. Disconnect the negative battery cable.
3. Disconnect the PCM harness connectors.

NOTE: 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.

4. Release the spring latch from the PCM.
5. Lift the PCM from the PCM mounting tray.
6. Remove the PCM from the engine compartment.

INSTALLATION PROCEDURE




1. Install the PCM to the PCM mounting tray.
2. Secure the spring latch to the PCM.
3. Connect the PCM connectors to the PCM.

NOTE: Refer to Fastener Notice in Service Precautions.

Tighten the PCM connector end fasteners to 8 N.m (71 lb in).

4. Connect the negative battery cable.
5. If a new PCM is being installed, program the PCM. Programming and Relearning
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