HEATER/BLOWER MOTOR WIRE(S) (+12V in run position only)
Most vehicles will have (1) blower wire; however some Fords, newer GM vehicles and Chrysler 94 and up
will have (2) or more blower wires. To locate these wire(s) probe for wire(s) that only show +12V when
the ignition switch is in the RUN position only. This wire(s) will not show +12V when the ignition switch
is in any other position.
1.If your vehicle has only (1) blower wire connect the WHITE WITH BLACK STRIPE wire from the 4-relay
harness to this wire.
2.If your vehicle has (2) blower wires, connect the WHITE WITH BLACK STRIPE wire to both.
3.If your vehicle has (3) blower wires connect the unused WHITE wire from the 4-relay harness to the
third blower 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 4-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 18-pin
harness securely as pictured.
4. Use electrical tape to wrap, be sure to cover about 2 inches on either side of connection.
Secure with wire ties as shown.
Use this method ONLY when connecting two separate wires end to end.
Wire Tie
Electrical Tape
Wire Tie
LOCATING & MAKING CONNECTIONS
4
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 18-pin harness and both large RED wires from
the 4-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 18-pin harness and (1) large RED wire from the
4-relay harness to one of these constant power wires. Then
connect the other large RED wire from the 4-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 18-pin harness and then strip back (1) of the (2) WHITE wires
from the 4-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 4-
relay harness and do not use.
3. If your vehicle has (2) ignition wires, connect the second WHITE wire from the 4-relay harness to
it.
4. If your vehicle has (3) ignition wires (some GMs) connect the second WHITE wire from the 4-relay
harness to both the second and third ignition wires in the vehicle.
