Door

DOOR

The door ajar switches are actuated by the mechanisms internal to the door latch. When a door is closed and properly latched, its door ajar switch is an open circuit. When a door is open or only partially latched, the door ajar switch is a closed circuit. The rear door ajar switches are hard wired in series between a body ground and the ElectroMechanical Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN). On vehicles not equipped with the optional memory system, the front door ajar switches are also hard wired in series between ground and the EMIC.

On vehicles equipped with the optional memory system each front door ajar switch is hard wired in series between ground and its respective driver or passenger Memory Mirror Module (MMM) located in the front door. The MMM then sends electronic door ajar switch status messages to the EMIC over the Controller Area Network (CAN) data bus. Both the EMIC and the MMM read the hard wired door ajar switch inputs through internal pull-ups, then use these inputs to control many electronic functions and features of the vehicle.

The door ajar switches as well as the hard wired inputs and outputs of the switches may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information.