Serial Data Control of Retained Accessory Power (RAP)
The class 2 modules receive the power mode message from the body control
module (BCM) over the serial data circuits, indicating when the retained accessory
power (RAP) power mode is current. The BCM monitors the ignition switch position,
battery condition and passenger compartment doors status to determine whether RAP
should be initiated. The modules then support the operation of the systems under their
control as required by their RAP power mode operation.
RAP will end when one of the following conditions is met:
| • | The BCM receives a class 2 message indicating the opening of any
compartment door. |
| • | The BCM internal timer for the RAP expires, after approximately 10 minutes. |
| • | The BCM detects a decrease in battery capacity below a prescribed limit. |
| • | The transition from OFF or UNLOCK to RUN of the ignition switch. |
The modules receiving serial data messages for RAP functions are:
| • | The driver door module (DDM) |
| • | The remote control door lock receiver (RCDLR) |
The DDM sends the corresponding message to the rest of door modules that are
in the power door serial data bus, allowing the operation of the power windows during
the RAP power mode.
Relay Control of RAP
The RAP relay is controlled by the RCDLR. The relay is energized in all power
modes, except Off Awake. The RCDLR has an accessory voltage signal, which is on in
RUN and ACC positions of the ignition switch. Therefore the RCDLR energizes the RAP
relay in the ACC position of the ignition switch, also.
The RAP relay provides power for:
