I have a 1999 dodge durango and want to know how to wire the driving lights (aftermarket install) to come on with the headlights. Im not sure but I think the headlights are positive ground. There are three wires in the headlight plug, but tested no power with lights on. The light kit came with a switch, I'd have to drill a hole somewhere on the dash to install it and I don't want to drill any holes in the dash. I just want to hook up the wires under the hood, so when the head lights are on so are the driving lights. thanks for any info.
I install them with a relay... use your parking light wire to trigger the driving lights rather than a switch on the dash... as for the pos and neg I can't remember what the durango has but most are a + at the light itself... relay pins as follows 86 to pk light wire on car 85 to ground 30 to a fused 12v ckt 87 to the + on your driving lights... if your parking lights are a neg trigger then pin 86 to parking light wire and jump 85 and 30 together on a fused +12v.. I'm sure there is a relay diagram here that will help...
Hymer
This can be done without a switch if you want. All the switch will do is turn them off if you do not want them on. There is a small difference to be aware of first, fog lights are to be connected to low beam and driving lights to high beam. Which lights do you have? If you do not wish to use a switch on these then there is no need to, the relay info above will get you on the right track. The first thing that you need to do is quit trying to do this using "the force". Do you have a meter?
Your headlights are not a positive ground, they are a negative ground just like every other gorund in your vehicle, what you have found is probably this. You went looking for a line to go to +12v when the lights were turned on and you could not find one. Those lights at the backside of the lights will have 3 wires. It is one of these two scenarios.
(1) 1 ground and 2 positive - 1 wire goes to +12v on low beam, the other on high beam
(2) 2 ground and 1 positive -1 wire goes to ground on low beam, the other on high beam
Chances are that it is option 1 and your light sabre wasn't grounded properly. Test by taking one side on the + terminal of the batt and the other probe on the - terminal. Do you have a reading, let there be light if it is a test light. Once you get your meter / test light / light sabre working properly and verify that it is working properly, we can get to work on the proper light wires.
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