Electronic Control Unit (ECM)

ECM Fasteners:

IMPORTANT PRECAUTIONS!
To prevent possible electrical damage to the ECM, NEVER touch the connector pins on soldered components on the circuit boards.
Always turn the key to OFF before disconnecting power supply to the ECM (for example; battery, fuses, ECM connector, jumper cables, etc.).

SERVICE INSTRUCTIONS
Service of the ECM should normally consist of either replacement of the ECM or a PROM change.
If the diagnostic procedures call for the ECM to be replaced, the PROM and ECM should be checked first to make sure they are the correct units for the vehicle. If they are, remove the PROM from the faulty ECM and transfer to the new ECM.
THE NEW ECM WILL NOT CONTAIN A PROM.
DTC 51 indicates the PROM is installed wrong or has failed. When DTC 51 is obtained, check the PROM for bent pins or poor contact in the PROM holder.
When replacing an ECM, it is important to transfer the broadcast code and the production number to the new unit.

REMOVE OR DISCONNECT
- Negative battery cable.
- Left "A" pillar panel.
- ECM fasteners.
- ECM connectors.
- ECM.
- PROM. PROM

INSTALL OR CONNECT
- PROM. PROM
- ECM into vehicle.
- ECM connectors.
- ECM fasteners.
- Left "A" pillar panel.
- Negative battery cable.