Lumina APV V6-191 3.1L VIN D TBI (1995)
Engine Control Module: Service and Repair
PROM Access Cover
CAUTION: To prevent possible Electrostatic Discharge damage to the Powertrain Control Module (PCM), Do Not touch the connector pins or
soldered components on the circuit.
Service of the PCM should normally consist of either replacement of the PCM or a Programmable Read Only Memory (PROM) change.
If the diagnostic procedures call for the PCM to be replaced, the engine calibrator (PROM) and PCM should be checked first to see if they are the
correct parts. If they are remove the PROM from the faulty PCM and install it in the new service PCM. THE SERVICE PCM WILL NOT
CONTAIN A PROM. Diagnostic Trouble Code (DTC) 51 indicates the PROM is installed improperly or has malfunctioned. When DTC 51 is
obtained, check the PROM installation for bent pins or pins not fully seated in the socket. If the PROM is installed correctly and DTC 51 still
shows, replace the PROM.
Important: When replacing the production PCM with a service PCM (controller), it is important to transfer the Broadcast code and production
PCM number to the service PCM label. Please do not record on PCM cover. This will allow positive identification of PCM parts throughout the
service life of the vehicle.
CAUTION: To prevent internal PCM damage, the ignition must be "OFF" when disconnecting or reconnecting power to PCM (for example,
battery cable, PCM pigtail, PCM fuse, jumper cables, etc.).
REMOVE OR DISCONNECT
1. Negative battery cable.
2. Right side sound insulator.
3. Vacuum center.
4. Connectors to PCM.
5. PCM.
6. PROM access cover.
7. PROM from PCM.
INSTALL OR CONNECT
1. PROM to PCM.
2. PROM access cover.
3. PCM.
4. Connectors to PCM.
5. Vacuum center.
6. Right side sound insulator.
7. Negative battery cable.
PROM
CAUTION: To prevent possible Electrostatic Discharge damage to the PROM or PCM, Do Not touch the component leads, and Do Not remove
integrated circuit from carrier.
DTC 51 indicates a faulty PROM, bent pins, or incorrect installation.
