Removal Procedure
- Open the rear compartment lid.
- Remove the forward rear compartment trim panel. Refer to Rear Compartment Trim Panel Replacement .
- Disconnect the OnStar® global positioning satellite (GPS) antenna coaxial cable (4) from the OnStar® VIU (5).
- Disconnect the 2 electrical connectors.
- Remove the VIU (5) by lifting the retainer tabs (3) upward.
- Remove the VIU (5) from the vehicle.
- The old VIU must be returned for core credit.
Important: The vehicle interface unit (VIU) 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.
Installation Procedure
- Record the 10-digit STID number from the label on the VIU module.
- Install the OnStar® vehicle interface unit (VIU) (5) into the module bracket assembly.
- Connect the 2 electrical connectors.
- Connect the OnStar® GPS antenna coaxial cable (4) to the VIU (5) until fully seated.
- Ensure the locking tabs (3) are secure to the VIU.
- Install the forward rear compartment trim panel. Refer to Rear Compartment Trim Panel Replacement .
- Reconfigure the OnStar® system. Refer to OnStar Reconfiguration .
- Close the rear compartment lid.
Notice: In order to avoid damage to the circuit board, do NOT over-tighten the thumb screws. Using your fingers, apply only a light pressure.
Tighten
Apply 0.2 N·m (2 lb in) of torque, or less, to the thumb screw electrical connectors.
Important: After replacing the VIU, you must reconfigure the OnStar® system. Failure to reconfigure the system will result in an additional customer visit for repair.
