h4 lights installed - no high beams

[rockerZ71]

I installed new h4 headlights w/ harness from Tom's the other night, and now when I turn on high beams I get nothing. High beams worked fine before. Just wondering if this is a common problem and someone can point me in the right direction before I start poking around with a multimeter tonight

thanks

 

[WheelHorse]

You hooked up both relays B+ and - wires?

Ensure the light socket you're using as a sensor is sending the power to the in feed on the high side.

You could also try swapping low beam relay and the high beam to rule out if it's a relay...if you're not comfortable with using a multimeter.

 

[rockerZ71]

will check it out tonight. Perfectly comfortable using a meter, just discovered the problem going to work and thought I'd ask if it might save me some time tonight. Wiring was complete, I didn't connect any of the relays - just had to connect 2 wires to the battery and 2 grounds (one for each light) - will verify the wiring is correct tonight

 

[PaveBronco]

I just had the same issue, swapped in a very well put together harness from hyghlndr, good price too. Thought I had a relay issue, but swapped out my dimmer foot switch and all is well, it had a lifetime guarantee so it didn’t cost me. I wonder if because the old headlight circuit is now only used to actuate the relays, the current draw is much less so now my gummed up switch wont let it flow?? Maybe, jumper the dimmer plug, see what happens..

 

[rockerZ71]

I just had the same issue, swapped in a very well put together harness from hyghlndr, good price too. Thought I had a relay issue, but swapped out my dimmer foot switch and all is well, it had a lifetime guarantee so it didn’t cost me. I wonder if because the old headlight circuit is now only used to actuate the relays, the current draw is much less so now my gummed up switch wont let it flow?? Maybe, jumper the dimmer plug, see what happens..

Thanks for the replies yall-

I checked that first and jumpering the switch had no effect. used my voltmeter on the drivers side and saw the voltage switch from one wire to the other when I switched beams. Tried the same on the passenger side (where it connects to the new harness), and sure enough, nothing on the high beam side.

So, if anyone sees this and knows where I should expect the wires to split off to each side, please let me know. The wires are wrapped up pretty well so undoing all that to trace it is a hassle - enough of one that I will probably put it off and live with just low beams for a long time (yeah I could wire it from the drivers side, but I prefer to fix the root cause rather than just make it work and if I do that it gives me an excuse to live with the bad wiring indefinitely). And I said earlier that my high beams worked before - I guess only one of them was probably working before and I just didn't notice. Don't really use them all that often but like to keep everything working.

Theres a bundle of wires including the headlight wires that goes through the firewall on the passenger side - its routed on the bottom lip of the dash over to the drivers side. The wires from the foot switch go to the bundle of wires routed under the dash, which also goes through the firewall on the drivers side. looks like the high beams are a green/black wire.

 

[Viperwolf1]

The split is near the dimmer switch. I recommend just testing the dimmer switch with an ohmmeter though.

 

[707Bronk]

X3 - Check dimmer switch

Then start following the circuit out to the headlights.

 

[rockerZ71]

the dimmer switch switched 12V to the high beam on the drivers side so I don't think its the switch - only 3 wires to the switch so the problem must be elsewhere right?

also does anyone happen to have the part number for the connectors that plug into the headlights (3 prong female) mine are in rough shape and would like to replace those

 

[WheelHorse]

At S-402 of course

Borrowed from this site:

http://www.bronco.com/technical/wiring.shtml

 

[PaveBronco]

Think Viperwolf posted this awhile ago, used it to UN-Fu@# my PO's wiring. now I got all my lights working, even reverse. first time in 20 years..
http://www.supermotors.net/registry/media/890070

 

[rockerZ71]

great, i appreciate the diagrams I've got some work to do but shouldnt be all that tough

 

[Kegger]

Had same prob with Hylanders harness Dumb a''' me cant see any more the green off the bronco aint ground. its black turned the dimmer into an on off swich low/ nothing swiched the wires and followed the colors and BAM. went and bought some 2.50 glasses can't see shi=== anymore. all is good

 

[rockerZ71]

thanks yall, these diagrams will help for sure. My dad is coming into town to stay with me this week so ive been trying to finish up some flooring ive been putting in so havent been working on the bronco yet but I'll get it fixed soon

 

[bstein]

No Hi Beams

I just installed the JBG system ( RJM Injection ) harness and Im having the same problems. I had a new dimmer on the shelf and its not the issue and did switch the relays. Will continue to watch the post hoping for pointers as well ..

 

[707Bronk]

Are these like the WH "Illuminator" harness where it utilizes one of your existing headlight sockets to activate the relays? Or do you replace the entire front headlight harness?

 

[bstein]

yes that is what the JBG / RJM system uses ..

 

[707Bronk]

I would check voltage at the socket of the original harness, might as well check the other socket as well (the one that is now taped up and unused).

If you see both high and low power at the OE socket, then it confirms that the stock portion of the wiring is good.

I would then look at the H4 wiring harness, draw a schematic of it, and see if it makes sense.

 

[KBUCK1]

Did you push the ground wire out of the back of the factory plug when installing the h4 bulb. I did on my new centech harness and the bright light didnt work on that side. Dim lights still worked though

 

[rockerZ71]

Are these like the WH "Illuminator" harness where it utilizes one of your existing headlight sockets to activate the relays? Or do you replace the entire front headlight harness?

yeah they plug right up - and actually now I am having problems with the lights cutting out from time to time and its because the original plugs (which I am using one of on the pass side) are in real bad shape and the contacts move around in them. So I am going to cut the connectors and solder the wires.

Did you push the ground wire out of the back of the factory plug when installing the h4 bulb. I did on my new centech harness and the bright light didnt work on that side. Dim lights still worked though

I don't think so, and I don't have the voltage I see when I switch to high beams present on the pass side (I do have it on the drivers side but it needs to be fixed on the passenger side for cleaner wiring)

I would check voltage at the socket of the original harness, might as well check the other socket as well (the one that is now taped up and unused).
.

yep - see above i have a problem somwhere, powers not getting to the plug on the passenger side for the high beams