I installed a lightbar and wanted to tie the relay into my brights. I've tested the relay on the lighting circuit and it works great, my dilemma is that when I turn any lights on it turns the lightbar on as well, marker, low, and high beams, the light bar stays on. I have tested it on all three circuits of the 9004 connection. I'm sorta at a loss right now.

When I use a lite circuit tester(I didn't use my voltmeter) these are the results I get.

0=No power
1=Power

Off - 0,0,0
Marker - 0,0,0
Low - 1,0,1
High - 0,1,1

The odd part is with the low and high beams its like the circuit just changed the direction of electrical flow rather than becoming a dead circuit. If I put the tester on the first 2 slots of the plug and switch back and forth between high and low the tester stays lit.

Edit: These numbers are looking at the 9004 plug(not headlight) head on with the clip on top.

 

I didn't 100% follow but 2nd Gens switch the ground. You can also switch the relay ground

 

That's what seemed like was happening. Thanks for the confirmation. Do you suggest I wire the + and - into the 9004 harness so its not grounding back to the battery directly and flowing through the light circuit instead? That would be the only thing I haven't tested with the relay. I am normally really good at figuring this stuff out but the reversing of the grounds really through me for a loop.

 

I frown on light bars . If using off road that's fine but not the street! Yesterday a guy in a tractor trailer had two led lights on top of the cab. He was a few cars behind me in the other lane and blinding me from the mirror! Upgrade the lighting not add more lights. You didn't say what the amp draw on the light bar is. Not wise to add it on to the high beam circuit. Use Feed power to the relay from the battery. You can use power going to the highs to trigger the relay.

 

I think what you are really frowning about is people who forget to turn their lightbar/brights off, people who don't care and keep them on, and people that are to stupid to know what the little blue light is on their dash. When tools are used properly and with curtesy for others there is nothing wrong with the use. I am a truck driver and get blinded by lightbars and bright headlights every single day or night at some point. I may flash my headlights at them but I never say they shouldn't have a light bar just that they should make sure its off at the right time. Some people have a hard time at night seeing and keep their brights on and so I try to give everyone the benefit of the doubt

I have upgraded the fixtures and the lights but being an older vehicle the new design hasn't helped much at all.

In every post I made here I talked about the relays I am using.

I live in the country. Nearest small town is 15 miles away and the nearest city is more than 2 hours. Bright lighting is a must where I live. We have a ton of deer in the area. I have stopped less than a mile from my house and counted over 50 head of deer in one of the neighbor's fields before. I have not gone more than a week without seeing a fresh kill on the side of the road. So light bars and bull bars are a must where I live. I want to tie the light bar into my brights so that it is faster and more convenient to turn them off when there is traffic around.

 

So use the trigger signal for the relay for the brights, to also activate the relay for your additional lights.

 

Thank you for your comment! Not sure why, but it did not cross my mind to use the same trigger wire that is triggering the brights relay. lol
As soon as I get the chance I am going to pull my fuse box and find that trigger wire so I can tie a relay into it. I think I will do the same with the reverse light trigger so I can add lights to that later.
I really hope I can find it without any trouble.

Thanks again. I'll update the thread when I know more or have been successful.

PS. I am going to do this to my other truck that I have been having a similar problem with trying to tie in the light bar. The voltage is to low on my 06 Ram so it would only trigger the relay or the light, not both.

 

Relay for the brights is gonna be in the PDC under the hood, I *believe* it switches the ground to activate the relay. (wiring diagrams will tell ya. ) Should be pin 85 in the relay socket, I think.

For the reverse lights, Just use the current wire that power the lights (assuming it is switched power there, and not switched ground.... need to check on that) to activate the relay instead, and the run a separate (heavy gauge) power feed for the relay to switch, and power ALL your backup lamps from that.