Content Theft Deterrent (CTD) System
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 Chevrolet Tahoe, 2003 Chevrolet Suburban, and 2003 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The Content Theft Deterrent function provides the theft deterrent by sounding the horn and flashing the headlamps and the park lamps when there is an unauthorized vehicle entry or there is tampering detected.