SECURITY Telltale
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The SECURITY telltale appears on the message center inside the instrument cluster. If the SECURITY telltale flashes or if the SECURITY telltale lights continuously during the vehicle operation, refer to the system diagnosis.