See also:

Immobilizer Operation (Keyless Access)
This vehicle has a passive theft-deterrent system. The system does not have to be manually armed or disarmed. The vehicle is automatically immobilized when the transmitter leaves the vehicle ...

Remote Keyless Entry (RKE) System Operation
The RKE transmitter will work up to 20m (65 ft) away from the vehicle. There are other conditions which can affect the performance of the transmitter. See Remote Keyless Entry (RKE) System . The ...

Accessories and Modifications
When you add non-GM accessories to your vehicle they can affect your vehicle’s performance and safety, including such things as, airbags, braking, stability, ride and handling, emissions systems, ...