Envoy 2WD V8-5.3L VIN M (2005)
Global Positioning System Module: Service and Repair
Communication Interface Module Replacement (TrailBlazer EXT, Envoy XL)
COMMUNICATION INTERFACE MODULE REPLACEMENT (TRAILBLAZER EXT, ENVOY XL)
REMOVAL PROCEDURE
1. Fold and tumble the right second row seat to a cargo position.
IMPORTANT: Do not exchange the vehicle communication interface module with other vehicles. Each vehicle communication interface module has
a specific station identification (STID) and electronic serial number (ESN). These identification numbers are stored in the General Motors vehicle
history files by VIN and used by OnStar(R) and the National Cellular Telephone Network.
2. Remove the protective cover (1) from the vehicle communication interface module (VCIM).
3. Remove the VCIM from the bracket by releasing the retaining tab (1).
4. Remove the electrical connectors from the VCIM.
5. Remove the VCIM from the vehicle.
INSTALLATION PROCEDURE
1. If replacing the VCIM, record the 10-digit STID number, and the 11-digit ESN number from the labels on the new module.
2. Position the VCIM near the mounting location.
3. Install the quick connector to the VCIM.
4. Install the remaining electrical connectors to the VCIM.
5. Install the VCIM (1) to the bracket.
