I have recently purchased these license plate holders that display a led message below the plate. The installation manual says I can connect the power wire to the brake light power to only come on during a stop, or to the power line that goes to the trunk and have it run constantly. I want to only have it come on when I am stopped. I also have to attach a ground wire. Any help on how I would do this would be appreciated!
2007-02-28 01:57:26 · 6 answers · asked by SigEpShawn 2 in Cars & Transportation ➔ Maintenance & Repairs
Yes you can indeed hook something up to the brake light power. I did this on a early 90's mustang I had which I mounted a neon license plate frame.
Use a test light and isolate the power wire from inside the trunk area where the wires hook onto the bulb. You can just unplug the harness and have someone stomp the brake, or wedge a broom handle so the pedal stays depressed and probe the leads of the harness. You can hook your test light ground to the trunk latch (anything bare metal attached to the frame will work as well) and when the test light illuminates you have found your hot wire.
3M makes some electrical connectors which I believe are called "scotch lock connectors" which allow you to slip one side of the connector over the existing wire and your new wire into the other side and use a pair of pliers to crimp down on the connector thus not cutting the OEM wire. Find a suitable ground for the license plate ( look for a screw somewhere inside the trunk area around the latch and loosen enough so you can wrap the stripped side of the ground wire around the bolt/screw and re-tighten around the stripped wire for a easy ground) and you are in business.
Hope this helps.
2007-02-28 02:27:13 · answer #1 · answered by monkey tuesday 3 · 1⤊ 0⤋
There are three wires to your tail light. One is ground. One is the running light. The other is the brake light.
You probably can see these wires in your trunk.
You need a cheap voltmeter to determine which is which, or find a schematic of the wiring diagram of your car. It will show you what color wire is which.
If you opt for a voltmeter or DC voltage probe, you can get one from Radio Shack for a few bucks. Read the book on how to use it, before you do anything. One mistake can blow it out!
Connect the black lead of the voltmeter to the chassis or body (if metal) of the car. A nut is a good point. Turn on your lights. Take the red lead and connect it to each of the wires. When the meter or light on the probe comes on, then this is the wire for the lights. Tag it and put it aside.
Turn your lights off. Now have someone push and hold down on the brake peddle. Repeat the same for the other two wires. The one that didn't come on is the ground. The other is your brake line. Follow your instructions and connect to these two wires.
If you have a foreign made car or a car with yellow turn signal lens, then do the same thing.
Lots of luck!
2007-02-28 03:09:12 · answer #2 · answered by Bigdog 5 · 1⤊ 0⤋
The easiest way is with a test light (sold at your parts store) and a friend. Disconnect the connector to the brake lamp assembly. Have your friend step on the brake for a few seconds repeatedly. test each wire until the light goes on each time he presses the brake. You have now located the brake light power wire. The light assembly should have a black wire that is attached to the body somewhere. This is the ground wire.
2007-02-28 02:05:10 · answer #3 · answered by yes_its_me 7 · 1⤊ 0⤋
You can hook it up to the brake light, as long as the signals are separate from the brake (unlike most pickup trucks). You should check the legality before you install it though. They are illegal almost everywhere, and could cost you a ticket if the officer chooses to write you one.
By the way, if the brake lamps and turn signal lamps are using the same bulb, you should hook it up to the third brake light bulb, otherwise it will probably screw up your turn signals on that side. the flasher unit uses the resistance in the bulbs to time the flash.
You can use anything metal in the body to ground it, like driving a screw into the trunk floor, etc.
2007-02-28 02:37:41 · answer #4 · answered by Ben H 5 · 1⤊ 0⤋
take a test light and while someone push the brake,you jab one of the wires that works the brake light and run the wire to it.if you have trouble finding the wire,take a long piece of wire and run it to the third brake light,in the back glass.
2007-02-28 02:07:03 · answer #5 · answered by Anonymous · 1⤊ 0⤋
attach it to the brake light wire so it only comes on when you hit the brakes. attach your ground wire to your frame
2007-03-06 03:47:25 · answer #6 · answered by bluesnature 1 · 0⤊ 0⤋