The door ajar indicator system consists of the following components:

The body control module (BCM) receives discrete inputs from each of the door latches from two independent circuits. The driver door ajar signal is independent of the passenger door ajar signal circuits, it has a specific circuit allocated to supply an input to the BCM. If any of the doors are open or not closed correctly, the contacts of the ajar switch are closed causing the voltage within the signal circuit to drop to zero. The BCM detects the drop in voltage and sends a serial data message to the IPC. The IPC, upon receipt of this message, will illuminate the door ajar indicator.

The IPC will also send a serial data message to the radio to activate the door ajar audible warning when the following conditions are met: