Circuit/System Description
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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. This is known as the retained accessory power (RAP) mode. The RAP mode will provide battery voltage to the sunroof module (if equipped) or the special equipment option (SEO) RAP relay (if equipped). For components such as the radio and driver door module (DDM), each will receive a message broadcasted on the communication buss requesting to remain powered ON in support of RAP mode.