With Vehicle Control Module (VCM)

Service of the Vehicle Control Module (VCM) consists of replacement of VCM. If the diagnostics call for replacement of the VCM, it will be necessary to transfer the Programmable Read Only Memory (PROM) and program the Electrically Erasable Programmable Read Only Memory (EEPROM) in the VCM using the procedure, refer to Prom or Mem-Cal Replacement. With Vehicle Control Module (VCM)

NOTE: When replacing the production VCM with a service VCM (controller), it is important to transfer the broadcast code and production VCM number to the service VCM label. This will allow positive identification of VCM parts throughout the service life of the vehicle. Also transfer the PROM.

CAUTION: To prevent internal VCM damage, the ignition must be "OFF" when disconnecting or reconnecting power to the VCM (for example, battery cable, Engine Control Module (ECM) fuse, jumper cables, etc.).


CAUTION: To prevent possible Electrostatic Discharge damage to the VCM, Do Not touch the connector pins or soldered components on the circuit board.

VCM Location:

PROM Unit Socket:

REMOVE OR DISCONNECT
1. Negative battery cable.
2. Connectors from VCM.
3. VCM mounting hardware
4. VCM from engine compartment.
5. VCM access cover.
6. PROM removal.

NOTE: Replacement VCM is supplied without a PROM, so care should be used when removing it from the defective VCM, because it will be reused in the new VCM.

Serving VCM:

^ Remove PROM by using thumb and first finger, gently squeeze each end of the blue PROM and pull upward.

CAUTION: Do not remove the cover of the PROM. Use of unapproved PROM removal methods may cause damage to the PROM or socket.


INSPECT

PROM Unit:

^ For alignment notches of the PROM and carefully set it aside. Do not open the PROM.

REMOVE OR DISCONNECT
1. New VCM from its packaging and check the service number to make sure it is the same as the defective VCM.
2. Access cover.

INSTALL OR CONNECT
1. PROM in PROM socket.

Press only on the ends of the PROM. Small notches in the PROM must be aligned with the small notches in the PROM socket. Gently press on PROM until it is firmly seated in the socket. Listen for the click.

2. Access cover on VCM.
3. VCM in engine compartment.
4. Connectors to VCM.
5. The Malfunction Indicator Lamp (MIL), antilock and brake lamps will continue to be enabled until the VCM is programmed. Once programming is complete, the lamps will be turned "OFF' and normal operation will occur.
6. Negative battery cable.
7. Proceed to EEPROM programming below.

FUNCTIONAL CHECK


^ Use Techline terminal/equipment to perform the Diagnostic (OBD) System Check,

OR

^ Refer to Diagnostic (OBD) System Check in System Diagnosis/Procedures. Testing and Inspection