Relay Controlled Power Mode (Without ATH/BTM)

The BCM uses the discrete ignition switch inputs Off/Run/Crank Voltage, Accessory Voltage and Ignition 1 Voltage, to distinguish the correct power mode. The BCM, after determining the desired power mode, will activate the appropriate relays for that power mode.

The retained accessory power relay remains on for a timed period after the Ignition key is removed. Refer to Retained Accessory Power Description and Operation  for more information on the retained accessory power function.