Serial Data Control of Retained Accessory Power (RAP)
The modules listed below 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:
| • | Vehicle Interface Unit (VIU) (if equipped) |
| • | Instrument Panel Cluster (IPC) |
| • | HVAC Control Module (w/ CJ2) |
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:
The BCM opens the RAP relay to end the RAP function when it ends the
RAP function as outlined in the previous text.
