Door Lock Cylinder Switch: Description and Operation

Fig. 1 Door Cylinder Lock Switch:

DOOR CYLINDER LOCK SWITCH
A door cylinder lock switch is snapped onto the back of the key lock cylinder inside each front door of vehicles equipped with the optional Vehicle Theft Security System (VTSS). The door cylinder lock switch is a resistor multiplexed momentary switch that is hard wired in series between a body ground and the Central Timer Module (CTM) through the front door wire harness. The door cylinder lock switches are driven by the key lock cylinders and contain three internal resistors. One resistor is used for the neutral switch position, one for the Lock position, and one for the Unlock position.

The door cylinder lock switches cannot be adjusted or repaired and, if faulty or damaged, they must be replaced.

The door cylinder lock switches are actuated by the key lock cylinder when the key is inserted in the lock cylinder and turned to the lock or unlock positions. The door cylinder lock switch closes a path to ground through one of three internal resistors for the Central Timer Module (CTM) when the front door key lock cylinder is in the Lock, Unlock, or Neutral positions. The CTM reads the switch status through an internal pull-up, then uses this information as an input for both power lock system and Vehicle Theft Security System (VTSS) operation.

The door cylinder lock switches and circuits can be diagnosed using conventional diagnostic tools and methods.