Electrical 1985 mustang gt Led conversion trouble

I am making a post here because I am in major need of some help. I have a 1985 Mustang gt 5.0 5 speed, I recently purchased an Led conversion kit from HIDnation.com its a 12k lumens 4656 and 4651 set. I also purchased a relay harness to accommodate for the new Leds, these are the links for the headlights and the harness

https://www.octanelighting.com/4-he...-4wAvX-jWWFBqxnlvRLt2EJ_Tj-oycVORmShTGvpKGnse

https://www.hidnation.com/products/h4651-led-conversion-kit

https://www.hidnation.com/products/h4656-led-conversion-kit?_pos=5&_sid=8d5e95e49&_ss=r

The current position I am in right now is, I have newly made grounds for all 4 headlights, I have my harness' male connector plugged into the driver side low beam oem female connector, my positive for my relay harness is connected to the positive on my solenoid. All of my headlights are functioning but they both come on when I turn on my low beams and the high beams won't turn off when I press the brights switch, also small problem my right dash arrow stays illuminated but all of the signals work just fine. I'm really at my wits end here I heard that I might potentially have to get a new relay harness which would be less than ideal because I spent all day soldering it to make all the connections reach. Now some people have told me that new Leds need to see a certain angle to know when to turn on and off and my headlights aren't mounted in the buckets yet for testing purposes but that doesn't seem right at all. One last thing, these Leds I got are pretty loud. Is there any way I can minimize that, If there isn't I'm just going to get a loud high pressure fuel pump.

Please Help me out yall I'm really lost, I do everything else but this electrical stuff has me stumped and I can't get anyone else to help me out on this. Thanks for your time.

LILCBRA said:

The thing that has me concerned is that the diagram states "Camaros only, omit for Firebird" - the harness itself should work just fine, but I'd be concerned on how they wired the plug. It could be that GM wired the positive connections in the plug opposite of how Ford did back then. So it could be that the high beam circuit is being activated at all times by the low beam circuit of the car.

First thing I'd suggest is to double check those connections to ensure they're in the proper place. Any one of them could be wrong, especially if the new harness is made for a different car.

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This was extremely helpful thank you very much. So in short I'm missing a trigger output for my high beams, that's because I only have one male connector for the trigger, correct? So what is my next move forward should I just bite the bullet, eat the 50$ and try to find a dedicated one that's on the same polarity and has 2 trigger outputs or I heard that you can modify these relay harnesses, Is that just going to be more hassle than it's worth? Also again, thank you so much I was so lost trying to find a solution.

LILCBRA said:

Here's the diagram for that section of the harness, it should help as well. It's in the red Haynes manual if you wanted to get your own copy. I find it extremely helpful specifically because it has the diagrams in the back of the book. Or you could purchase color coded diagrams from someone on ebay. They've been shared on the site somewhere but I haven't looked to grab a link.




The short story: you'll want to connect the high beam relay trigger to the LG-BK wire and the low beam relay trigger to the R-BK wire. Since I can only assume that the harness you've purchased was made specifically for a Camaro/Firebird, you may need to cut and splice the new harness to make it work.

The book:

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Thank you so much brother. I appreciate it so much this is the exact help I needed.