Communication Interface Module Replacement

Preliminary Procedures

1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
2. Pull back the left rear compartment trim panel in order to expose the communication interface module.
3. For programming and set up, Refer to Control Module References .

• The vehicle communication interface module (VCIM) has a specific set of unique numbers that tie the module to each vehicle. These numbers, the 10-digit station identification and the 11-digit electronic serial number, are used by the National Cellular Network and OnStar® to identify the specific vehicle. Because these numbers are tied to the vehicle identification number of the vehicle, you must never exchange these parts with those of another vehicle.
• After replacing the vehicle communication interface module, you must reconfigure the OnStar® system. Failure to reconfigure the system will result in an additional customer visit for repair. In addition, pressing and holding the white dot button on the keypad will NOT reset this version of the OnStar® system. This action will cause a DTC to set.
• When replacing the VCIM be sure to transfer Bluetooth Antenna, if equipped.