Circuit/System Description

WARNING: This page is about a different car, the 2017 GMC Acadia. However, it is still accessible from the selected car via links, so may be relevant.

The body control module (BCM) controls the ignition circuit by applying voltage to the retained accessory power relay coil control circuit. The ignition circuit is energized during all power modes except OFF - awake. The ignition circuit is also energized for approximately 10 min after shutting the vehicle OFF, providing no door is opened.

The keyless entry control module controls the retained accessory power relays through a control circuit by applying voltage to the interruptible retained accessory power relay coil control circuit. The devices are energized when the ignition is in the ACCESSORY or the ON position. They are also energized for approximately 10 min after shutting the ignition OFF, providing no door is opened. The keyless entry control module will also deactivate the interruptible retained accessory power relay coil control circuit during transmitter authentication. The purpose is to deactivate components that may cause radio frequency (RF) interference when the ignition mode switch is pressed and may result in a "NO REMOTE DETECTED" message displayed on the driver information center.