2004 Cadillac SRX Owner's Manual - Page 246

Theft-Deterrent Feature THEFTLOCK is designed to discourage theft of your radio. Your vehicle has a "built in" theft-deterrent feature on each radio that is automatic - there is no programming required. The radio in your vehicle cannot be used in any other vehicle. When the radio was originally installed in your vehicle at the factory, it stored the Vehicle Identification Number (VIN). Each time the ignition is turned on, the VIN is verified. If the vehicle's VIN does not match the VIN stored in the radio, THEFTLOCK® will be activated and the audio system will not play. If the radio is removed from your vehicle, the original VIN in the radio can be used to trace the radio back to your vehicle. ® Audio Steering Wheel Controls Some audio controls can be adjusted at the steering wheel. They include the following: > (Mute): Press this button to silence the system. Press this button again to hear the sound. SRCE (Source): Press this button to choose FM1, FM2, AM, or XM1 or XM2 (48 contiguous US states, if equipped), radio, or CD. 3-124