Retained Accessory Power Description and Operation

 Retained Accessory Power

The body control module (BCM) monitors the ignition switch position, battery condition, and each door ajar/open switch status to determine whether the retained accessory power should be initiated or terminated. Retained accessory power is controlled by two different methods; relay control and serial data. Some modules receive a retained accessory power message from the BCM over the serial data circuits. Serial data controlled retained accessory power is deactivated as required by their modules retained accessory power mode operation. Other subsystems are activated directly by the BCM through a relay. Components and systems that are active in retained accessory power are also activated anytime the ignition is any position other than OFF regardless of the door switch signals.

 Relay Controlled Retained Accessory Power

The BCM keeps the relay energized during all power modes, except Off-Awake and Crank. The relay is also energized for approximately 10 minutes after shutting the ignition OFF and removing the key, providing no door is opened.

Relay controlled retained accessory power will end when one of the following conditions is met:


• The BCM receives an input from any door ajar or open switch indicating the opening of any door after the ignition key is out of the ignition.

•
Note

If the BCM is receiving any door ajar or open signal from those switches when the ignition key is turned OFF, retained accessory power will not initiate.


 The BCM internal timer for the retained accessory power expires after approximately 10 minutes.
• The BCM detects a decrease in battery capacity below a prescribed limit.
Systems powered by the accessory relay during the retained accessory power mode are as follows:


• Accessory power outlet center console compartment
• Cigar Lighter
 Serial Data Controlled Retained Accessory Power

Retained accessory power systems controlled by serial data are as follows:

 Radio

Activation/deactivation of retained accessory power for radio is the same as the relay function with one exception. The open door switch is the only door switch that turns off the radio with retained accessory power.