© 2001 Directed Electronics, Inc. Vista, CA
9
wiring the door lock system
The easiest way to determine which type of door lock system you are working with is to remove the master locking
switch itself, which is usually on the driver’s door or on the center console. Once you have determined which type
of factory door lock circuit you are working with, and the color codes of the switch wires to be used, you can
usually simplify the installation by locating the same wires in the vehicle’s kick panel. If no central locking switch
is found, the installation may require a door lock actuator.
NOTE:
Always retest the wires in the kick panel to be sure they work the same as the wires on the switch.
There are eight common types of door lock circuits:
TYPE A: 3-WIRE (+) PULSE CONTROLLING FACTORY LOCK RELAYS
Most GM, some Ford and Chrysler, 1995 and newer Saturns, some new VW, newer BMW.
TYPE B: 3-WIRE (-) PULSE CONTROLLING FACTORY LOCK RELAYS
Most Asian vehicles, early Saturn, some BMW and Porsche.
TYPE C: DIRECTLY-WIRED REVERSING-POLARITY SWITCHES
The switches are wired directly to the motors. This type of system has no factory relays. Most Fords, many GM
two-doors cars and trucks, many Chryslers.
TYPE D: ADDING ONE OR MORE AFTER-MARKET ACTUATORS
These include slave systems without an actuator in the driver’s door, but with factory actuators in all the other
doors. Type D also includes vehicles without power locks, which are having actuators added. All Saabs before
1994, most Volvo (except 850i), most Subaru, most Isuzu, and many Mazdas. Some mid-eighties Nissans, pre-1985
Mercedes-Benz and Audi.
TYPE E: ELECTRICALLY ACTIVATED VACUUM SYSTEMS
The vehicle must have a vacuum actuator in each door. Make sure that locking the doors from the driver's or pas-
senger side using the key activates all the actuators in the vehicle. This requires a slight modification to the door
lock harness. Mercedes-Benz and Audi 1985 and newer.
TYPE F: ONE-WIRE SYSTEM - CUT TO LOCK, GROUND TO UNLOCK
This system is found in the late-model Nissan Sentra, some Nissan 240SX, and Nissan 300ZX 1992 and later. It is
also found in older Mitsubishis, and some early Mazda MPV’s.
identifying the door lock system
