Engine Control Module (ECM) Replacement

ENGINE CONTROL MODULE (ECM)
Service of the ECM should normally Consist of either replacement of the ECM or a MEM-CAL change. If the diagnostic procedures call for the ECM to be replaced, the Memory-Calibration unit (MEM-CAL) and ECM should be checked first to see if they are the correct parts. Also, perform the "ECM Replacement Check" chart in this section before replacing an ECM to assure that the replacement ECM will not be damaged. The PROM can easily be checked using parameter P.2.5. If the part numbers are correct, remove the MEM-CAL from the faulty ECM and install them in the new service ECM.

THE SERVICE ECM WILL NOT CONTAIN A MEM-CAL, so care should be taken when removing the MEM-CAL from a defective ECM which is being replaced. Trouble Code F32 (No ECM Data) indicates the MEM-CAL is installed improperly or has malfunctioned. If Code F32 is current, check to see if the MEM-CAL is fully seated. If not fully seated, press firmly on the ends of the MEM-CAL and make sure the retaining clips have locked. If the MEM-CAL is installed correctly and Code "B334" still shows, diagnose using the procedure outlined DTC F32. After replacement of an ECM, clear stored codes, and check the vehicle for proper operation.

NOTICE: To prevent internal ECM damage, the ignition must be "OFF" when disconnecting or reconnecting power to ECM (for example, battery positive cable, ECM connectors, ECM fuse, jumper cables, etc.).









Remove or Disconnect

1. Right hand hush panel.

2. Connectors to ECM.

3. ECM retaining nut

4. Pull ECM down.

5. Bracket, and front mounting pin.

6. MEM-CAL cover and MEM-CAL.

Important: Perform the ECM Replacement Check. ECM Replacement Check

Install or Connect

1. Old MEM-CAL in new ECM.

2. Bracket and mounting pin.

3. ECM

4. ECM retaining nut.

5. Connectors.

6. Hush panel.