Operation CHARM: Car repair manuals for everyone.

Principles of Operation (How Does it Work?)

Power Door Locks
The central security module controls the power door lock and keyless entry system. The lock and unlock operation is carried out by supplying ground to the central security module from the door lock control switch. The normal path of the actuators is to ground through the central security module. The door lock control switch will lock and unlock all doors by grounding the appropriate circuit to the central security module. The central security module then supplies power to the appropriate common actuator circuit to lock or unlock all doors.

Keyless Entry
The keyless entry remote transmitter sends a frequency that is received by the central security module internal antenna. Depending on the frequency received, the central security module will lock all doors or unlock the driver door. If the unlock frequency is received again within five seconds of the first unlock, the central security module will unlock all doors.

If the frequency received is for the panic button, the central security module will cycle ground to the park lamp and horn. The park lamps and horn will continue to cycle until the panic button is pressed again or the ignition switch is turned to the RUN position.