GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Important: 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.

  1. Remove the I/P center trim panel. Refer to Instrument Panel Center Trim Panel Replacement in Instrument Panel, Gages, and Console.

  2. Object Number: 815865  Size: SH
  3. Remove the screws that hold the communication interface module to the I/P.

  4. Object Number: 865085  Size: SH
  5. Disconnect the antenna and the electrical connections from the communication interface module.
  6. Remove the communication interface module.

Installation Procedure

  1. When replacing a VCIM, record the 11-digit electronic serial number (ESN) and the 10-digit station identification (STID) number from the label on the new VCIM.

  2. Object Number: 865085  Size: SH
  3. Connect the electrical and the antenna connections to the communication interface module.
  4. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 815865  Size: SH
  5. Install the communication interface module screws.
  6. Tighten
    Tighten the screws to 2 N·m (18 lb in).

  7. Install the I/P center trim panel. Refer to Instrument Panel Center Trim Panel Replacement in Instrument Panel, Gages, and Console.
  8. Important: 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.

  9. Reconfigure the OnStar® system. Refer to OnStar Reconfiguration .