Serial Data Control of Retained Accessory Power

Modules listed below all receive a Retained Accessory Power (RAP) messages from Body Control Module (BCM) over class 2 serial data circuit. BCM monitors ignition switch position, battery condition and passenger compartment door status to determine whether RAP should be initiated. BCM then sends a message to listed modules initializing RAP power mode. Modules then support operation of systems as required by RAP power mode strategy of individual modules.

RAP will end when any of following conditions are met:

• BCM receives a hardwired input indicating opening of a passenger compartment door.
• After 10 minutes BCM receives message from internal timer indicating end of RAP period.
• BCM detects a decrease in battery capacity below a prescribed limit. BCM then sends a serial data message to listed modules ending RAP function.

The modules receiving class 2 serial data messages for RAP functions are:

• Radio.
• Instrument panel cluster.