Circuit/System Description
WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The body control module (BCM) is the power mode master and will monitor the status of the ignition switch and the doors. When necessary conditions are met, the BCM provides battery voltage to specific components for a predetermined amount of time. The retained accessory power (RAP) mode will provide battery voltage to the sunroof module (if equipped) or the special equipment option (SEO) RAP relay (if equipped).