BMcEL

It will definitely work, you just have a bottleneck that limits the overall capacity of the harness. Will it ever reach capacity? No, but why under-engineer it, especially when the only difference is about a foot of wire.

This only applies if you run high/low beams at the same time. Wasn't trying to bash what you did, just pointing out the bottleneck.

You're talking about voltage drop due to length...this has nothing to do with what I posted above (drawing twice as much power on one part of the circuit in relation to the rest of it). There is virtually zero change in capacity between 1 and 5 feet of cable, so there would be virtually zero change in power reaching the headlights.

BMcEL

Tinning just prevents corrosion and makes soldering easier.

drmix

So for my harness I am running a 10 gauge wire from the battery to the fuse block. Do you think this will be alright to do the lows with the highs at the same time? Everything else is 12 gauge.

shaeff

Absolutely, so long as all your connections are done well.

BMcEL

Even 12awg is overkill but there's nothing wrong with that. That's what most people use, myself included.

streetlancer

iTrader: (1)

Wouldn't a drawback to that setup be that if the fuse blew you would lose both high and low beams at the same time? Whereas, if you had a separate feed for both high/low it would be either one or the other meaning you'd still have light.

drmix

Sweet just making sure. The only thing I dont like is my so called "heavy duty" H4 pigtails that I had ordered turned out to only be 16 gauge. Everything else is soldered and heat shrunk together.

How much more can I run through the fuse box using just the one 10 gauge going to the battery. I am planning on my highs, lows, and a cb for now.

Cant wait to throw in the H4s when they come in this weekend.

streetlancer

iTrader: (1)

Yup, those "HD" pigtails are wimpy,lol. I've tried finding just the connectors themselves but no luck;the best i found was 14 gauge.

What housings and bulbs are you using drmix? I kinda like these:


^ That's superbleeder's truck btw..

drmix

I bought the usual euro 200mm housing that everyone buys.
http://cgi.ebay.com/ws/eBayISAPI.dll...m=270381702877

For now I am just going to use the bulbs that come with the housing until I get around to ordering some better bulbs. I was thinking about getting the philips xtreme vision which are suppose to be the brightest bulb you can legally run.
http://www.powerbulbs.com/product/ph...eadlight-bulbs

drmix

So I am having trouble with my harness. My H4 lights didnt come in today like they should have so I figured I would see how much just the wiring would help. Heres how I got my relays set up:
*86 goes to the old harness
*87 goes to the new harness
*30 goes to the fuse panel
*85 goes to battery which is connected throughout the whole new harness

When I turn on my headlights I checked voltage at the relay and have voltage on 86 which I should and of course got power on 30.

For some reason power is going into the relay like it should but isnt coming out and going to the bulb. I also seen on your diagram that your wiring to the relay is a little different. Maybe because you are using a different relay? But this is the relay I am using http://www.oreillyauto.com/site/c/de...&keyword=84601

Any ideas?

drmix

Kinda confusing the way I explained my setup so heres the diagram I used to wire everything up

worshipmentor

iTrader: (3)

not sure if this is the same as on my 87 but I think on mine the two wires that come from the old headlight plug are providing a switched GROUND not a switched power. try connecting a power source (fused battery) to the 85 terminal letting the 86 terminal provide the ground. not positive but I think that's how mine is wired.

BMcEL

The only difference is I used the ground from the factory H4 connector to ground the relays...that's the proper way to wire it.

drmix

Would that make mine not work? It seems like a ground from the battery and the new harness would provide a better ground.

Do the numbers on the relays always mean the same thing on other relays? I was looking at other diagrams for 30 amp relays and there are a few different methods of wiring them up

xxxtreme22r

That's my diagram BTW. I did have to change something, but for the life of me I can't remember what it was. I forgot all about having to change that diagram. Use 4crawlers diagram. I do know that I didn't need that diode to keep the highs on with the lows. I think the high beam indicator light has something to do with having enough current running through it to trip the low beam relay.

You might have to switch the wire on the factory plug to the opposite side. Where it shows it connected to the left prong, try the right prong. I know my relays are still grounded to the body and not the OEM plug.

Pins 85 and 86 are switchable BTW, it doesn't matter in which direction power flows through that. I don't know if that's what's confusing on the relay or not.

In BMcEL's diagram you can see where his are flopped around from mine between 85/86. Then on his the COM and HI on the OEM plug are flipped as opposed to mine. That's where I think the problem is.

drmix

But if im not even connecting to the OEM common why would I have to flip the common and the high?


On 4crawlers diagram the only difference I seen was his 86 and 85 were switched and that he was using the OEM common.

Im gonna head outside and try a couple things. If you have any more ideas let me know.

BMcEL

In my schematic (and 4crawler's) the H4 is positioned as if you were looking at the back of the connector. xxxtreme's is looking at the front of the conenctor. Swapping high/common will definitely cause problems.

BMcEL

Part of what you're doing with the harness is converting the headlights from switched ground to switched power. It is important to maintain the switched ground setup for tripping the relays...this means using the factory wiring across terminals 85/86. Do not ground the relays to the body.

drmix

Alright so I figured it out. I guess you must use the common from the OEM harness to activate the relays otherwise it wont work. Once I switched that they work right away.

Thanks for all the help everyone.

Cant wait till its night time so I can see how much of a difference just the wiring will help. Hopefully tomorrow my H4s will be in so I can see how much of a improvement that will help.

BMcEL

Just ordered a set of these.



I'll be sure to get some before and after shots of the cutoff...crap ebay housings vs Autopal.