Retained Accessory Power (RAP)

RETAINED ACCESSORY POWER (RAP) DESCRIPTION AND OPERATION

SERIAL DATA CONTROL OF RETAINED ACCESSORY POWER (RAP)
The modules listed all receive a RAP 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 listed modules telling them that they are in RAP power mode. The modules then support the operation of the systems under their control as required by their RAP power mode strategy.

RAP will end when one of the following conditions are met:
- The BCM receives a hardwired input indicating the opening of a passenger compartment door.
- 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 BCM then sends a serial data message to the listed modules ending the RAP function.

The modules receiving serial data messages for RAP functions are:
- Radio
- Instrument Panel Cluster (IPC)

RELAY CONTROL OF RETAINED ACCESSORY POWER (RAP)
When the body control module (BCM) is in the RAP function as described above, it closes the RAP relay. This provides power during the RAP period for the following:
- Sunroof
- Power Windows

The BCM opens the RAP relay to end the RAP function when it ends the RAP function as outlined.