VCM Replacement/Programming Overview

Notice: In order to prevent possible electrostatic discharge (ESD) damage to the VCM, do not touch the connector pins or soldered components on the circuit board.

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

Important: 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.

Service of the VCM consists of either replacement of VCM or reprogramming of the EEPROM. If the diagnostics call for replacement of the VCM, it will be necessary to transfer the PROM and program the EEPROM in the VCM using the procedure in this section of the manual.

VCM Replacement/Programming With KS Calibration PROM

1. Disconnect the negative battery cable.

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.




2. Remove the connectors from the VCM.
3. Remove the spring retainer off and over the rail of the VCM.

Slide the VCM out of the bracket at an angle.




4. Remove the VCM access cover.



5. Remove the PROM/Knock Sensor (KS) module.



6. Inspect for the alignment notches of the KS Calibration PROM.
7. Carefully set it aside.
8. Do not open the KS Calibration PROM.
9. Remove the new VCM from the packaging.

Check the service number in order to make sure it is the same as the defective VCM.





Important: 

•	The Knock Sensor (KS) module must be transferred to the replacement VCM.

•	The replacement VCM is supplied without a EEPROM program, the replacement VCM must be programmed before the vehicle will run.

•	Using the thumb and first finger, remove the KS Calibration PROM by gently squeezing each end of the blue KS Calibration PROM

•	Do not remove the cover of the KS Calibration PROM. Use of an unapproved KS Calibration PROM removal methods may cause damage to the KS Calibration PROM or the socket.

10. Remove the access cover.

Notice: In order to prevent possible electrostatic discharge (ESD) damage to the VCM, do not touch the connector pins or soldered components on the circuit board.

Important: Press only on the ends of the KS Calibration PROM. Gently press on the KS Calibration PROM until it is firmly seated in the socket. Listen for the click.

1. Align the notches of the KS Calibration PROM with the notches in the KS Calibration PROM socket.



2. Install the KS Calibration PROM in the KS Calibration PROM socket.



3. Install the access cover on the VCM.
4. Install the VCM in the engine compartment.



5. Install the connectors to the VCM.
6. The MIL, antilock and brake lamps will continue to be enabled until the VCM is programmed. Once the programming is complete, the lamps will turn off and normal operation will occur.
7. Connect the negative battery cable.
8. Proceed to the EEPROM programming. Go to EEPROM Programming for V6 applications. Refer to EEPROM Programming for V8.