Serial Data Control of Retained Accessory Power (RAP)
WARNING: This page is about a different car, the 2004 Pontiac Sunfire and 2004 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
The radio receives a power mode message from the body control module (BCM) over the serial data circuits. The BCM monitors the ignition switch position, battery condition and passenger compartment door status to determine whether RAP should be initiated. The BCM then sends a message to the radio telling it that it is in the RAP power mode.
RAP will end when one of the following conditions are met:
- The BCM receives an input from the driver door jam switch.
- The BCM receives a message from its internal timer indicating the end of the RAP period after 10 minutes.
- The BCM detects a decrease in battery capacity below a prescribed limit.
- The ignition switch transitions from OFF to RUN/ON or ACC.
The BCM then sends a serial data message to the radio ending the RAP function.