GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


    Object Number: 1210957  Size: SH

    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 right rear body side trim. Refer to Body Side Rear Trim Panel Replacement .
  2. Remove the nuts securing the OnStar® module to the vehicle body.

  3. Object Number: 1211090  Size: SH
  4. Disconnect all the electrical connectors from the module.
  5. Remove the module from the vehicle.

Installation procedure


    Object Number: 1211090  Size: SH
  1. When replacing the 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. Reconnect the electrical connectors the module.
  3. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1210957  Size: SH
  4. Install the module onto the vehicle.
  5. Tighten
    Tighten the nuts to 9 N·m (80 lb in).

  6. Install the right rear body side trim. Refer to Body Side Rear Trim Panel Replacement .
  7. 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.

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