How to Add a Backup Alarm
- 1). Set the emergency brake on your vehicle.
- 2). Turn the ignition key on your vehicle to run, but do not start the vehicle's engine.
- 3). Move the shift lever to reverse to turn-on your vehicle's back-up lights.
- 4). Connect the ground wire of the 12-volt test light to a bare metal part of the vehicle's frame, bumper or sheet metal.
- 5). Penetrate the insulation of the wires leading to the vehicle's rear tail light assembly, one at a time, until you locate the one that turns on the test light. This is the wire that feeds the back-up light.
- 6). Locate a position on the chassis of your vehicle to mount the back-up alarm. The exact location will depend on the model and size of the back-up alarm you choose and the model of your vehicle. The location should be toward the rear of the vehicle, shielded as much as possible from road hazards and in a spot you can access with the tools needed to attach the alarm to the chassis. Mount the alarm to your vehicle.
- 7). Connect the negative or ground wire of the alarm securely to one of the studs bolting the alarm to your vehicle.
- 8). Connect the positive wire of the alarm to the wire you identified as the back-up light feed using a Scotch-Lock solderless connector. If the positive wire of the alarm is too short to reach the back-up light wire, lengthen the positive wire with a length of 16-gauge, copper automotive wire, connected with a solderless butt connector.
- 9). Support the wires firmly against the frame or chassis of the vehicle with nylon wire ties.
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