4
LOCATING & MAKING CONNECTIONS
Note: Remove any paint below
the spade connector.
Factory Bolt
Spade Connector
Black Ground Wire
Please see the wiring chart on our website, www.bulldogsecurity.com.
CONSTANT POWER (+12V, key in any position including off)
These wire(s) are in your vehicle’s main ignition harness, usually located on the steering column coming
from the ignition switch. Probe each wire with your test light. The correct wire(s) will show +12V when
the ignition switch is in these 5 positions (ACC-LOCK-OFF-RUN-CRANK).
1. If your vehicle has only (1) constant power wire, attach the
RED wire from the 12-pin harness and both large RED wires from
the 3-relay harness to the constant power wire in the vehicle.
2. If your vehicle has (2) constant power wires, attach the RED
wire from the 12-pin harness and (1) large RED wire from the
3-relay harness to one of these constant power wires. Then
connect the other large RED wire from the 3-relay harness to the
second constant power wire in the vehicle.
Make sure to wrap electrical tape around all (3) fuse holders to prevent shorting to ground.
IGNITION HARNESS
UNDER DASH
IGNITION WIRE(S) (+12V in run and crank position only)
The ignition wire(s) are also located in the main harness coming from the ignition switch. Probe each
wire with your test light, the correct wire(s) will show +12V only when the ignition switch is in the
RUN AND CRANK positions only. The correct wires will not show +12V when in the OFF or ACCESSORY position.
Most Ford, GM, and Chrysler vehicles have at least (2) ignition wires. Most foreign vehicles have only
(1).
1. Strip back the YELLOW wire from the 12-pin harness and then strip back (1) of the (2) WHITE wires
from the 3-relay harness and twist both of these wires together.
2. Connect the YELLOW wire and the WHITE wire from step (1) to the ignition wire in the main harness.
If your vehicle has only (1) ignition wire, tape off the end of the second WHITE wire from the 3-
relay harness and do not use.
3. If your vehicle has (2) ignition wires, connect the second WHITE wire from the 3-relay harness to
it.
4. If your vehicle has (3) ignition wires (some GMs) connect the second WHITE wire from the 3-relay
12-pin harness to both the second and third ignition wires in the vehicle.
ACCESSORY WIRE(S) THAT POWER THE HEATER/BLOWER MOTOR
(+12V in run or on positions) This wire is also in the main ignition switch harness usually located in
the steering column. Make all connections as close to the ignition switch harness as possible.
Most vehicles will have (1) accessory wire; however some Fords, newer GM vehicles and Chrysler 94 and
up will have (2) or more accessory wires. To locate these wire(s) probe for wire(s) that only show +12V
when the ignition switch is in the RUN or ON positions. This wire(s) will not show +12V when the ignition
switch is in any other position.
1.If your vehicle has only (1) accessory wire connect the WHITE WITH BLACK STRIPE wire from the 3-relay
harness to this wire.
2.If your vehicle has (2) accessory wires, connect the WHITE WITH BLACK STRIPE wire to both.
3.If your vehicle has (3) accessory wires connect the unused WHITE wire from the 3-relay harness to the
third accessory wire.
STARTER/CRANK WIRE (+12V only in the start position only)
The starter/crank wire is also in the main harness. Locate the wire that shows +12V only in the crank
position. This wire will not show +12V in any other position. Attach the YELLOW WITH BLACK STRIPE wire
from the 3-relay harness to this wire.
CHASSIS GROUND
Locate an easy to get to bolt or screw
located under the driver’s side of the
dash and attach the BLACK ground wire
from the 12-pin harness securely as pictured.
PARKING LIGHTS (+12V only with parking lights on)
Turn the parking lights to the ON position. (NOT YOUR HEADLAMPS).
Probe the wire(s) coming from your headlamp control switch. Find
a wire that will show +12V only when the parking lights are ON.
Connect the BROWN wire from the 12-pin harness to this wire. If
this wire tests as a (-) negative, see diagram.
DO NOT USE THE RED WIRE, TAPE OFF.
87a
To (-)Parking
Light Output
To Ground
Brown wire
from harness
To Ground
YELLOW
BLACK
WHITE
BLUE
RED
Optional part #775 required.
NEGATIVE PARKING LIGHT OUTPUT