There are 3 basic system types:
“Type A” Door Lock Test (Most GMs and most Chryslers)
Probe both of your door lock wires going to the door lock switch these wires are usually located in
the driver’s kick panel, attach one end of your test light to a good chassis ground. Using the vehicle’s
door lock controls, activate the lock then the unlock testing both wires one at a time. If the test
light illuminates when you probe the lock and the unlock wires your vehicle has a “Type A” door locking
system. Make sure to mark which wire is lock and unlock.
“Type B” Door Lock Test (Most Imports, some newer Fords)
Probe both door lock wires going to the door lock switch these wires are usually located in the driver’s
kick panel. Attach one end of your test light to +12V using the vehicle’s door lock controls activate
the lock then the unlock testing both wires one at a time. If the test light illuminates when you probe
the lock and the unlock wires your vehicle has a “Type B” door locking system. Make sure to mark which
wire is lock and unlock.
“Type C” Door Lock Test (Most Fords, some Chryslers, GM Trucks)
Using your test light probe both the lock and the unlock wires usually located in the driver’s kick
panel. Attach one end of your test light to ground probing both wires one at a time while locking and
unlocking the doors with the driver’s side switch (usually the master switch). The test light should
illuminate in both switch positions. Now attach one end of your test light to +12V constant, probe both
wires one at a time again. The light should then illuminate again only in reverse order. This tells you
that you have a “Type C” reversing polarity system. Make sure to mark which wire is lock and unlock.
TESTING DOOR LOCK TYPE
LOCATING AND DETERMINING YOUR DOOR LOCK TYPE
In most cases, the factory door lock wires will be smaller gauge and located in the driver’s kick panel or
under the driver’s dash.
NOTE: To help determine your door lock type, refer to the Door Lock Types by Manufacturer chart on page 13
or visit our web page at www.bulldogsecurity.com for specific detailed information on a particular vehicle.
If the year of your vehicle is listed as having two or more types of door lock systems, you must test for
all of those types.
CONNECTING DOOR LOCKS
“Type B” (-) Negative
Ground
Yellow Antenna
Keep as straight
as possible, tape
the end to hold
straight.
NOTE: Connect the PURPLE WITH BLACK STRIPE
wire from the fuse to ground.
UNLOCK
LOCK
RED
BLACK
BLUE/BLACK Unlock
BROWN/BLACK Not Used
PURPLE
PURPLE/BLACK
GREEN/BLACK Lock
WHITE/BLACK Not Used
KEYLESS MODULE
FUSE
Ground
+12V Constant
“Type A” (+) Positive
NOTE: Connect the PURPLE WITH BLACK STRIPE
wire from the fuse to +12V constant
power.
UNLOCK
LOCK
RED
BLACK
BLUE/BLACK Unlock
BROWN/BLACK Not Used
PURPLE
PURPLE/BLACK
GREEN/BLACK Lock
WHITE/BLACK Not Used
KEYLESS MODULE
+12V Constant
Yellow Antenna
Keep as straight
as possible, tape
the end to hold
straight.
FUSE
Ground
+12V Constant
5
