2005 Cadillac XLR Owner's Manual - Page 190

Audio System(s) Notice: Before adding any sound equipment to your vehicle, like a tape player, CB radio, mobile telephone, or two-way radio, make sure that it can be added by checking with your dealer. Also, check federal rules covering mobile radio and telephone units. If sound equipment can be added, it is very important to do it properly. Added sound equipment may interfere with the operation of your vehicle's engine, radio, or other systems, and even damage them. Your vehicle's systems may interfere with the operation of sound equipment that has been added improperly. Figure out which audio system is in your vehicle, find out what your audio system can do, and how to operate all of its controls. Your vehicle has a feature called Retained Accessory Power (RAP). With RAP, the audio system can be played even after the ignition is turned off. See Retained Accessory Power (RAP) on page 2-22 for more information. Theft-Deterrent Feature THEFTLOCK® is designed to discourage theft of your vehicle's radio. The feature works automatically by learning a portion of the Vehicle Identification Number (VIN). If the radio is moved to a different vehicle, it will not operate. 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. With THEFTLOCK® activated, the radio will not operate if stolen. 3-78