Alarm Module: Service and Repair

Theft Deterrent Module Replacement

Warning

Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

For Vehicles equipped with OnStar(R) (UE1) with Back Up Battery:

The Back Up Battery is a redundant power supply to allow limited OnStar(R) functionality in the event of a main vehicle battery power disruption to the VCIM (OnStar(R)module). Do not disconnect the main vehicle battery or remove the OnStar(R) fuse with the ignition key in any position other than OFF. Retained accessory power (RAP) should be allowed to time out or be disabled (simply opening the driver door should disable RAP) before disconnecting power. Disconnecting power to the OnStar(R) module in any way while the ignition is On or with RAP activated may cause activation of the OnStar(R) Back-Up Battery (BUB) system and will discharge and permanently damage the back-up battery. Once the Back-Up Battery is activated it will stay on until it has completely discharged. The BUB is not rechargeable and once activated the BUB must be replaced.

Removal Procedure




1. Remove the lower steering column cover panel screws.
2. Turn the steering wheel in order to access the upper steering column panel screws. Remove the upper steering column cover panel screws.
3. Remove the upper and the lower steering column cover panels.




4. Disconnect the electrical connector from the immobilizer control unit.




5. Remove the immobilizer control unit.

Installation Procedure




1. Install the immobilizer control unit.
2. Connect the electrical connector to the immobilizer control unit.





Note: After replacing the immobilizer, the keys must be re-authorized using the key coding procedure. Refer to Programming Theft Deterrent System Components (Programming Theft Deterrent System Components).

3. Install the upper and the lower steering column cover panels.

Caution: Refer to Fastener Caution (Fastener Caution).

4. Install the lower steering column cover panel screws and tighten to 3 Nm (27 lb in).
5. Turn the steering wheel in order to access the upper steering column panel screw holes. Install the upper steering column cover panel screws and tighten to 3 Nm (27 lb in).
6. Connect the negative battery.