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Discussion Starter #1
The store-bought relay harness I bought for my 67 vert had one of the light terminals just pull out if the crimp while I was doing the install. Initially I just fixed the crimp and soldered it for good measure, then I got to overthinking it and decided I really wanted to have a separate relay for my GT/fog lights and wanted it all in one neat package.

so... I found all the plugs and terminals I needed pretty easily on amazon. Then got my kid to 3D print this fuse/relay mount for me (File from thingverse). I had to mod the print a little to get the universal relays to fit, but it turned out ok, I think.

I beefed up the 12v supply wire as well as the grounds with 10g wire. The rest was done with 14g.

I think I will mount it to the front of the rad support right by the battery, and then make a cover/splash shield out of some scrap kydex I have.
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Here are my wiring diagrams for headlamp relays and "50-state" fog light relay that automatically shuts off the fogs with the high beams as is required by most state laws. Feel free to use, copy, pass along, etc. Nice work on the mounting BTW.

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Thanks, @Woodchuck. I copied the wiring from my store bought harness and added the separate relay for the fog lights. I did think about ways to encorporate the 50-state legal functionality but decided to just keep the fogs working independently as they do with the factory 67 harness. If I ever pull this apart again, maybe I will do it that way.
 
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@Woodchuck... just trying to learn a bit more about wiring relays and lights...

your diagram above show the fog light switched on the ground side. Where as all my factory and upgraded wiring has the positive voltage switched. (Am I wrong?)

given The three relay mount I am currently working with,, And wanting to use the factory switches to signal the relays for all High/Low/Fog... how would you wire them in?

Is There a way to do this with just the three relays?
 
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@Woodchuck... just trying to learn a bit more about wiring relays and lights...

your diagram above show the fog light switched on the ground side. Where as all my factory and upgraded wiring has the positive voltage switched. (Am I wrong?)

given The three relay mount I am currently working with,, And wanting to use the factory switches to signal the relays for all High/Low/Fog... how would you wire them in?

Is There a way to do this with just the three relays?
You can switch them either on the positive or ground side. I like using the ground side as you really only need one wire from the relay to the [grounded] switch. With the positive you need a hot wire to the switch and another from the switch to the relay. Using the ground side you can circuit-protect your component.... power-fuse-relay-component..... without the need to circuit protect the switching side.
 

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Discussion Starter #7
thanks to Woodchuck for the feedback.

here is some more detail on how I wired things.
Disclaimer.
I am not a trained electrician, and I didn’t even stay at a HollidayInnExpress last night! So please don’t copy my wiring without doing your own research and being prepared to take responsibility for your own work. 😀
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Like I said before, I tried to duplicate the way my Cheap store bought harness was wired for the High/low beam relays. i wanted the fuses in the box, so that’s an obvious change.

I understand how the 87a (5th) terminal works on the low beam relay, but don’t totally understand why they would toggle the power from 87a(low beam) over to the 30(high beam). I see that it keeps that relay from being (hot) unless the low Beam signal is off, But seems like the high beam wouldnt have a switch-signal to 85/86 anyway.. right?

what I almost tried to do, was to run power from the (low beam) 87 over to the (flood)30. Thinking that would only energize the flood light relay when low beams were on and would get me the “50 state“ legal fogs.

I decided not to do this because, that would have to whole lighting harness on one single fuse (I think). And it seems like it would be better to have the fog lights drawing power directly from the battery, instead of stealing amps from the low beams..

perhaps... it wouldn’t have mattered. .. so I thought I went the “safe” route.
 

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Finally put the new harness into the car this morning. I am very happy with the results.

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Nice work, and thanks for the detailed write up
 

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Finally got out on my first evening drive with the new lights. I cant believe I waited so long to do this. The combination of the relay driven, modern headlights, and the fog/driving lights is practically a night and day difference compared to the old original lights.
 

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I used the Delta H4 housings. I think used either 50w or 60w halogen bulbs. I just wanted a decent set of lights to test out before spending a lot on bulbs. These are so much better than what I had, I will probably keep it as is.

The Fogs are just the sealed bulbs sold by CJ pony as part of their fog light conversion. They actually do a better job than I was expecting of lighting up the close/ground area in front of the car.
 

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Great write up! Proof positive you don't need to jump to LED lights for good lighting, you just need modern wiring.
 

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Discussion Starter #16
So did you use your schematic from post #7 or did you make changes
That's the wiring I stayed with and installed. The only significant change that is not shown on the diagram, is I ran a 10g ground wire from both headlights and tied it together to a more solid ground near the frame. *perhaps this wasn't necessary, but using my test light, I found the weathered metal surfaces near the headlight buckets were not giving me a very solid ground.

**If I ever pull this apart again, I might find a way to link the fog lights so they are only active when the low beams are on, but as I have it now, it works just like a factory install where (for better or worse), the fog lights operate independently from the headlights.
 

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The best place for a ground on that is to the battery neg or to where the ground wire from the battery is to the block or wire from there to the frame..
Ground are extremely important, a weak ground will do some crazy stuff to an electrical system..
 

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The best place for a ground on that is to the battery neg or to where the ground wire from the battery is to the block or wire from there to the frame..
Ground are extremely important, a weak ground will do some crazy stuff to an electrical system..
GROUNDS! Absolutely! Years ago, I paid no attention to them, thinking they were a tricial part of an electrical system.
However, come to find out how so many of my off-and-on electrical woes were due to weak grounds.
 

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Finally got out on my first evening drive with the new lights. I cant believe I waited so long to do this. The combination of the relay driven, modern headlights, and the fog/driving lights is practically a night and day difference compared to the old original lights.
Amazing, isn't it? doing the H4 housings and relay pack was the best money I've spent in years.


GROUNDS! Absolutely! Years ago, I paid no attention to them, thinking they were a tricial part of an electrical system.
However, come to find out how so many of my off-and-on electrical woes were due to weak grounds.
I preach this constantly. I read an article 10-15 years ago about automotive electrical troubleshooting and the importance of grounds in modern vehicles. The author estimated the unnecessary repairs/parts replacements due to bad grounds to be in the billions per year.
 
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