SECURITY Telltale
WARNING: This page is about a different car, the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The SECURITY Telltale on the message center is controlled by both the VTD system and the CTD system. The SECURITY telltale is a part of the reconfigurable message center on the instrument cluster. The SECURITY telltale is controlled by the body control module through the class 2 data line.
- The VTD system contained in the BCM commands the instrument cluster to control the SECURITY telltale only when the ignition switch is ON. The VTD system uses the telltale as a malfunction indicator.
- The CTD system also contained in the BCM commands the instrument cluster to control the indicator only when the ignition switch is OFF. The CTD system uses the SECURITY telltale to identify system status.