Subinoobi Posted November 18, 2014 Share Posted November 18, 2014 So I have a 90 loyale that I swapped DL quad headlights into, and I figured the easiest way to do the wiring would be to do an h4 quad plug harness upgrade that has relays and gets power straight from the battery. Now loyales have 9004 plugs, so I cut the plug and soldered in the correct h4656 plug and I know its wired right. The problem I'm having is if I turn on my low beams my high beams come on too, and the high beam light in my dash is on but very dim. Then I go to high beam and it will work sometimes but often I have to tap the relays. Then I go back to low and they work like they should but the high beam light is still on but dim. Is there some sort of relay that could be interfering? I know its not the relays in the harness because I swapped them for known good ones and it still did it. My thoughts are a faulty harness but if anyone else has encountered a problem like this I would love some input. Thanks guys! Quote Link to comment Share on other sites More sharing options...
Gloyale Posted November 19, 2014 Share Posted November 19, 2014 You do know that the Hi/Lo function of the factory wiring is done through the ground side right? So the factory bulb gets 1 wire with power from the relay....then grounds one or the other circuit through the column switch. So......IDK how you have things run....but the Hi/Lo wires from the harness should trigger the GROUND side of either the Hi or Lo relay. 1 Quote Link to comment Share on other sites More sharing options...
Subinoobi Posted November 19, 2014 Author Share Posted November 19, 2014 You do know that the Hi/Lo function of the factory wiring is done through the ground side right? So the factory bulb gets 1 wire with power from the relay....then grounds one or the other circuit through the column switch. So......IDK how you have things run....but the Hi/Lo wires from the harness should trigger the GROUND side of either the Hi or Lo relay. Yeah I discovered that with my multimeter last night. But I would think if the reverse polarity made a difference in the relay then it would just not work period, instead of having inconsistencies. I mean the only thing that is consistent is that my high beam light in my dash is very dimly on and when I first turn my lights on my high beams are on, but after playing with they switch they work normal. but if the polarity was it I would think it would not work like normal under any circumstance. I could be wrong I'm not an electrical genius though Quote Link to comment Share on other sites More sharing options...
DaveT Posted November 19, 2014 Share Posted November 19, 2014 There are relays that have polarity sensitive coils. Quote Link to comment Share on other sites More sharing options...
Subinoobi Posted November 21, 2014 Author Share Posted November 21, 2014 Alright got another harness and it does literally the exact same thing. So I'm gonna go with the polarity being the issue. I'm gonna get some relay harnesses and convert the polarity to what it should be and that will hopefully solve my problems. Quote Link to comment Share on other sites More sharing options...
wagonist Posted November 21, 2014 Share Posted November 21, 2014 So you've cut the existing plugs off the headlights and then joined in these other plugs? There would have been 3 wires. There is a 1 common wire, and one for high beam, and the last for low beam. If you put a multimeter across those wires you'll get 12v to find the different circuits. For low beam, you must pick that low beam wires to one side of the trigger of the relay, and the other side of the trigger goes to the common wire. You don't earth the other side of this trigger. It's a common mistake. On aftermarket relays, these will be the pins labelled 85 & 86. For the high beam, you do the same for that relay with the high beam wire. Then run a fused wire from your battery to pin 30, then 87 & 87a to the headlights. Then earth out the other side. Is this how you've got it wired? Quote Link to comment Share on other sites More sharing options...
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