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B. Installing the wiring harness:
This type of harness has three wires. The Red wire is for constant power, the White wire is
for ignition, and the Black is for ground.
Do not plug harness into device when making connections!
Searching for Correct Wires:
In order to find to correct wires, you must first set your multi meter to DCV or DC voltage
12V or 20V, attach the negative (-) probe to the vehicle chassis ground, and then begin
probing the wires you suspect of being the constant and ignition power sources.
Important:
When searching for the correct wires, DO NOT use a test bulb circuit tester.
Often, damage to vehicle computers and vehicle air bag restraint systems result from the
use of a test bulb causing a short circuit. Ideally, the use of a digital multi meter is the best
tool to search for the correct wires.
The appropriate pow er w ires should be found in the vehicle’s ignition harness
(See Chart A for the most common color codes for most vehicles)
How to Find Constant Power:
Locate the wire that you suspect would have constant power. Probe the wire with the meter
lead. Turn the vehicle’s ignition on and off while metering the wire. This wire should read a
constant 12 volts or higher when the ignition is in both the “ON” and “OFF” positions.
Strip the insulation back and connect the red wire from the tracking unit’s harness to this
constant wire using the hook and wrap technique (See diagram A on the following page).
Solder the connection to ensure a quality contact. Refer to Chart A for the most common
colors for a constant power connection.
How to Find Ignition (switched) power:
Locate the wire that you suspect to have ignition (Switched) power. Probe the wire with the
meter lead.
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With the key in the ignition and turned to the “ON” position (Not starting the
vehicle), the wire should meter 12 volts or more.
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With the lead still probing the wire, start the vehicle. When the car is cranking, the
wire’s voltage should not drop by more than 2 volts.
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Turn the key to the “OFF” position, the voltage should drop down to 0.
