Operation

OPERATION

The door cylinder lock switches (also known as the Central Locking/CL rotary tumbler switches) are actuated by the mechanisms internal to the door latch. When a door is closed and properly latched, its door cylinder lock switch is an open circuit. When a door is open or only partially latched, the door cylinder lock switch is a closed circuit. The door cylinder lock switches are hard wired in series between a body ground and the Body Control Module (BCM) (also known as the Signal Acquisition and Actuation Module/SAM). The BCM reads the hard wired door cylinder lock switch inputs through internal pull-ups, then uses these inputs to control many electronic functions and features of the vehicle. The BCM also sends electronic door cylinder lock switch status messages over the Controller Area Network (CAN) data bus.

The door cylinder lock 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.