headlight relays

[xs-style]

Can those of yall who have done headlight upgrades post pics of the relays installed in your trucks? I'm trying to make sure I get them placeds and wired in correctly. There's plenty of threads with 'hey look at my new lights' but not so much on the particulars of the job. Thanks everyone

[imjeff]

I kind of hide mine. Just use the wiring diagrams and use your imagination on where to mount the relays. I got a bunch of double relay holders that work very well. Make sure you use a big wire with breaker from your battery.

[ssxty8]

This should help you, even when it's for a 4 lamp set up.

IMO, space to locate or hide the relays shouldn't be a problem in our trucks. LOL

[Tx Firefighter]

On my 63.



On my 72.

[rich weyand]

My relays came as one unit about the size of a pack of ciggies. I just set it on top of the battery and left it there. It's more or less held in place by the wiring.

[83GMCK2500]

I will be relaying my '83 one of these days as well. I recently did my '96, rebuilt the entire front lighting harness, relays, and diodes added where necessary. I went to a wrecking yard and grabbed a 4-relay bracket from mid-late 90's S-series with the weatherpack sealed Bosch relays and went to work on it. Not that it helps you right now, but I stashed mine under my ECM.

These might give you some ideas:

[xs-style]

I'm looking for something along the lines of the first pic tx firefighter posted. I've seen the wiring diagrams, but I'm not well versed at that kind of thing. I'd much rather see pics and verify that I'm doing this right. On a side note, there are thre wires going to the bulb on my front signal light. I figure one is power one, ground, and what's the third one for?

[ssxty8]

Originally Posted by xs-style

On a side note, there are thre wires going to the bulb on my front signal light. I figure one is power one, ground, and what's the third one for?

In a signal bulb, like the 1157, at the front of the car, one is ground, and one each for park, and signal, which totals three. At the rear, one is ground, one is park, and the third is stop/signal. A 1156 will have only two wires due to being a single filament used on some configurations which use a separate lamp for stop, and another lamp for signal. The 1157 makes both jobs, for being a dual filament. The 7" head lamp is also a dual filament, so you'll have three wires at the connector, one ground, one low beam, and the third high beam.
Found this harness on ebay, that might ease the install for you. One thing I'd do is replace the relays with better ones, but if it's wired correctly, I should be really easy to install on your truck.
http://www.ebay.com/itm/CERAMIC-H4-H...fe72e7&vxp=mtr
Hope this helps.

[superwade57]

I recently looked at 94 s10 that a Guy put a small block in...point being I've never looked under the Hood of one Annert noticed a handy relay holder on the firewall thought it was a good option for clean relay install in our squares. I think it had 5 or 6 relays

[monte0185]

I dont have a rear shot but if you look you can see the two silver screws underneath the breather opening. Thats where the relays are and the harness is just ran out of the hole in front just below that and ran with the stock harness.

[xs-style]

Man this is just not working.I guess I'm just gonna have to give up on this one. I need a clear pic of where the relays mount and which wires they connect to or this idea is done. Stock headlights are better than none.

[imjeff]

Mount them where it's convenient on your truck. It's not like there is a single place they have to go. Haven't you found the wiring diagram?

[xs-style]

Well you guys have said there's no set place, and I get that. And yes, I've looked at the daiagrams and pulled threads from 3 forums for a week now trying to get a clear idea of what I'm doing but I'm apparently just not that smart here cuz its not clicking. To the drivers headlight there are six wires. 2 blacks for grounds, 2 greens and two browns. From there I'm lost. I have 4 wire, 30 amp relays. I found a good video on youtube that showed me exact what each of the wires was for. I figured I'd ask on here and someone would have done this before and had a picture or write up I could follow to tell me exactly how to hook it up. But either I'm not being clear or no one has what I need.

[Tx Firefighter]

Let me see if I can type this in such a way as to clear up your confusion.

"You have 6 wires on your left headlight. Two greens, two browns, two grounds"

The reason you have two greens and two browns is that one of each is the power coming in from the switch. The other pair of each is the power coming out of the plug and passing over to the right side headlight. The right headlight will only have one of each coming in. Does that make sense ? The truck feeds the left headlight and then a pair of wires jump off of that plug and run over to the other side to feed the other headlight.

You're gonna use the two wires that come from the light switch, through the firewall and down to the core support. Those are your power wires from the switch. One green, one brown. Those will activate your two relays. The green to one relay and the brown to the other.

Then, you will build the rest of the harness. The factory stuff can be removed other than those two wires from the switch I mentioned above that you connected to each relay.

The harness you will build will be in two parts. One part is a nice big fused wire from the battery to the relays. It will split at the end, to go to both relays. You will also build a short little ground wire from each relay to a nearby bolt or screw.

Let's recap so far.....

1) the factory green wire from the light switch goes to one relay (terminal 86 on the relay)
2) the factory brown wife from the light switch goes to the second relay (also terminal 86)
3) a big fused power wire runs from the battery and splits into two and connects to terminal 30/51 on each relay
4) a ground wire is connected from terminal 85 of each relay to a ground point

Now, you're almost done.

From terminal 87 of the green relay, run a split wire to each headlight where the factory green wire used to connect

Then, from terminal 87 of the brown relay, run a split wire to each headlight where the factory brown wire used to connect.

That's it.

[AcampoDave]

Thumbs up to Kevin for explaining this so beautifully. (What ever happened to that guy anyway? He was a top notch contributor around here.) I did this today and it went without a hitch.