Dakota Quad Cab 2WD V8-5.9L VIN Z LDC (2002)
Door Switch: Description and Operation
DOOR AJAR SWITCH
The door ajar state is used as an input for various control modules on the vehicle. The DRB III will display the state of the door ajar switches in
Inputs/Outputs. It's important to note, that when a door is closed, the switch state of the DRB III will show OPEN, and when the door is open, the
switch state will show CLOSED. During diagnosis, if a door is closed and the DRB III displays the switch state as CLOSED, it indicates a shorted
door ajar circuit. If the door is open and the DRB III displays the switch state as OPEN, it indicates an open door ajar circuit.
The door ajar switches close a path to ground for the Central Timer Module (CTM) when a door is opened. The passenger side front door and both
rear door ajar switches are connected in a parallel-series circuit between ground and the CTM, while the driver side front door ajar switch is
connected in series between ground and the CTM to provide a unique input. The CTM reads the switch status through an internal pull-up, then
sends the proper switch status messages to other electronic modules over the Programmable Communications Interface (PCI) data bus network.
The door ajar switches can be diagnosed using conventional diagnostic tools and methods.
The door ajar switches are integral to the door latches on each door The switches close a path to ground for the Central Timer Module (CTM)
when a door is opened.
The door ajar switches cannot be repaired and, if faulty or damaged, the door latch unit must be replaced.
