Headlight problems?

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meanwire
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Headlight problems?

Post by meanwire » Sun Nov 28, 2010 9:24 pm

I just recently purchased my Dad's '77 Bronco. Oh what great memories! Anyways he told me that the front headlights would intermittently turn off.
So I took it for a test drive and noticed that the headlights would turn off on high-beam. Any body encounter this problem and came up with a fix? He said he's installed new headlights.
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Post by Stan » Sun Nov 28, 2010 9:45 pm

My '68 does the same thing ( with Halogen lights) - I just don't use hi beam. :)
No issue with the '76
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Post by highbronco » Sun Nov 28, 2010 9:55 pm

Mine done the samething. I replaced dimmer switch(no luck). Then cleaned all grounds and connections at headlights(stayed on a little longer before going out). Put in new headlight switch(not any better). Bought a new heavyduty headlight switch(napa)2x the money as stock switch, But they haven't gone out yet. Just my experience. Hope it helps and Welcome aboard. Where at in C entral Oregon you from?
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Post by meanwire » Sun Nov 28, 2010 10:06 pm

Thank you for all the quick replies! High Bronco how long ago did you replace with a new heavy duty headlight switch since you had the same problem and how much was the switch? I'm form Prineville, Oregon.
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Post by highbronco » Sun Nov 28, 2010 10:33 pm

Been in there about 4 months. Got about 100 nitetime miles on it. It cost around $35. Their stock one was about 15 or so.
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Post by Muzzman » Mon Nov 29, 2010 8:50 am

I've had head light problems with older fords. It's usually been a loose wire at the head light switch.
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Post by Tom Dummer » Mon Nov 29, 2010 12:23 pm

Check for loose wires and if I remember right, theres a breaker attached to the back of the switch that can eventually fail. Little box about 1/2" by 3/4"
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Post by Viperwolf1 » Mon Nov 29, 2010 7:12 pm

The headlight switch has thermal circuit breakers built in. The current draw from the high beams causes the breaker to open until it cools off. Headlight relays are the cure and you will gain brighter lights.
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Post by Stan » Mon Nov 29, 2010 9:24 pm

What's the best way to wire a relay into the headlight system?
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Post by Arsenio » Mon Nov 29, 2010 10:34 pm

easyest is probably to buy a harness for it. I mounted two relays on fire wall the light switch flips the relay power goes through directly to headlights. Pretty strait forward wiring. A nice clean pre packaged kit looks better.

http://rjminjectiontech.com/?p=8
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Post by Viperwolf1 » Mon Nov 29, 2010 11:31 pm

Stan wrote:What's the best way to wire a relay into the headlight system?
Stan
The kits are hard to beat for the price. Here is how I wired mine up 20 some odd years ago.
Attachments
headlight relays.jpg
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Post by oldwinghunter » Mon Nov 29, 2010 11:32 pm

i set all of mine under the hood at the drivers side wheel well , run a harness to power, and ground, then take a lead from all of the light signals that come through the fire wall , hook up the relays, then send the signal off to the perspective light. when you turn on the switch, the corresponding relay does all of the work.

people make fun of the looks of my system, but it always works...

mabie if you just leave out, the psychodelic colored wire loom?
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Post by Stan » Tue Nov 30, 2010 9:36 am

Always like your schematics Viperwolf. They're so much easier to read than those photocopied reprinted 10,000 times ones I find in the manuals.
I've never made fun of your wiring David. I like the muitcolored conveluted tubing mixed with the polished diamond plate. :) Sure better than my 42 year old brittle, sliced and diced wiring mixed with the previous owners all blue rewire job and my own creative wiring :lol:
It looks like either way i go i'm basicly just tieing relays into the wires that lead to the headlites and then running a power source to the relays?
Should i run new/replace the wires from the relay to the headlamp sockets or is the old wiring ok?
You guys have a harness in mind ? I see WHs has an " illuminator " harness. $70
Stan
Oh i'm just running halogen headlamps - no H-4 or any of that hi tech stuff
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Post by Arsenio » Tue Nov 30, 2010 11:01 am

my link not clear enough for you. it has all new wires going from the out plug on the firewall to the plugs on the back of the headlights. Looks like wh sells the rjm harness or one very simiular. bc sells it also I know how much you want to give chuck some more money :roll: :mrgreen: actually the rjm harness looks a little better has an extra weather pack connector might make it easier to work on.
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Post by Stan » Tue Nov 30, 2010 11:51 am

Actually I didn't " click" on it. With dialup I'm real leary
of clicking on links. And this friggin piece of crap At&t/ I phone combo has been overloaded all week. - But I will give it a try
:lol:
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Post by Arsenio » Tue Nov 30, 2010 11:55 am

well you can spend 30-40 on relays, wire, weather packs. or spend 70 on something that is plug and play. ryan had these on special for t day for 50 bucks i think. so might be onsale again for xmas. yeah well enjoy the retirement I fear your generation is the last that is going to be able to retire.
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Post by Stan » Tue Nov 30, 2010 12:47 pm

Thanks for the info I'll look into it.
The headlights work fine - except when on hi beam :lol:
it's not like it's dark and rainy for the next 4 months.
Don't think I can get to it before the tree run/ "overniter" but maybe I can get luck and they'll have the x-mas sale.
Stan
I'm afraid you might be right about being able to retire. I'm hoping mine will last long enough for me to " get out" :lol: that might be better than going back to work. ;)
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Post by 69brightbluebronco » Tue Nov 30, 2010 3:27 pm

i have heard good things about this kit
http://www.eautoworks.com/product-eAuto ... 189849.htm
headlight relay harness for 20$ plus shipping....
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re: headlight problem

Post by summerscheifer » Tue Dec 14, 2010 12:05 am

Hey guys. i own Ford Focus 2.0 RS but my both headlights wont work and i don't even know how to adjust that? :roll: is anyone have an idea for this kind of situation?do i need to buy some auto parts? any help would be appreciated. thanks

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Re: re: headlight problem

Post by Scodge » Tue Dec 14, 2010 4:02 pm

summerscheifer wrote:Hey guys. i own Ford Focus 2.0 RS but my both headlights wont work and i don't even know how to adjust that? :roll: is anyone have an idea for this kind of situation?do i need to buy some auto parts? any help would be appreciated. thanks
Check your fuse then check your bulbs. If it isn't either of those, you need to go to the dealership.
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Post by DirtDonk » Wed Dec 15, 2010 3:52 pm

You might have to look into the owners manual to see how to change bulbs too. With so many changes to headlight design over the last few years, every car is different from the other, and even that changes within the model every couple/few years too. With our old Broncos, it's 3 screws and the light is out. With yours, you might just be able to reach behind the lamp and easily unscrew the retainer ring. Or, you might have to remove 35 other things just to get to it! Or, like my Buick, you might be able to un-do two clips and the whole assembly pops out in your hand and you can then get to the bulb.
In your case, you should at least check the bulbs, but with both out at the same time, it's probably a relay under the hood or a switch. Either way though, you'll need some experience to track them down, and a volt-ohm meter to check them out. From your question though, it sounds like you don't have that handy little tool yet. No time like the present to learn, but it does help to have someone looking over your shoulder the first time too.

Since we're just old truck owners here though, have you looked into any Ford Focus specific web forums yet? Not that we don't want to help, but anybody that is on one of those forums would have far more direct knowledge than most of us here would.

Good luck either way though. Sorry I couldn't be more help.

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Post by Puff Daddy » Sun Oct 09, 2016 1:06 pm

Hey, I hate to bring back an old post, but I'm having this problem now. I've read through this, and still don't see any definitive answers.

Anybody have a clear solution to the high beam problem before I start buying parts?
Tom

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Post by DirtDonk » Sun Oct 09, 2016 10:08 pm

The definitive solution (assuming you have the same problem) is to modernize your system with relays. Either in a harness you build yourself, or with something like this: http://www.wildhorses4x4.com/product/Ni ... ht-Harness
I'm sure Tom's has them as well, as do most of the other vendors. Very well worth the price of admission.

What's happening, especially on high-beams, is just what Viper said back then. The internal breaker is just overloaded, even with a new switch. But an older switch might be even more susceptible to it due to a general weakening of the contacts and higher resistance in the components.
Which is probably why highbronco saw a result when he cleaned his grounds. Resistance builds up heat, and heat means more load and the breaker trips. Old wires, brighter headlights and these old systems where all the power to the lights runs through 20 feet of wire and through the main switch and the dimmer switch just makes it practically inevitable that we'll experience this.

The relays (which most modern vehicles use starting in the '70's) take 99% of the electrical load off the switches and runs a more direct path to the headlights.
This means you not only reduce the risk of tripping the breaker, but you almost always end up with brighter headlights as well.

So beg, borrow, steal, buy or build a relay harness and there's a 99% chance that will fix your issue.
If it doesn't, then you have something unusual going on. If it's just erratic behavior at any time, it's usually the dimmer switch. But relays can still make for brighter headlights, and that's rarely a bad thing.

Paul
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3.5" WH/Skyjacker Lift
33 x 11.50 x15 Thornbirds on 15x7 Enkei's
Kayline soft top
Hanson bumpers
Dual batteries, Large 1G alt.

WWW.WILDHORSES4X4.COM :mrgreen:

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Post by Puff Daddy » Fri Oct 14, 2016 9:03 pm

Thanks Paul. I guess I just found my next project.
Tom

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Post by Puff Daddy » Fri Nov 10, 2017 7:46 pm

highbronco wrote:Mine done the samething. I replaced dimmer switch(no luck). Then cleaned all grounds and connections at headlights(stayed on a little longer before going out). Put in new headlight switch(not any better). Bought a new heavyduty headlight switch(napa)2x the money as stock switch, But they haven't gone out yet. Just my experience. Hope it helps and Welcome aboard. Where at in C entral Oregon you from?
Does anybody have a part number for this heavy duty headlight switch? I went to Autozone and they'd never heard of it.

Also, can anybody tell me the locations of all the grounds associated with the headlights. Still unable to make my high beams work. Here's what I've done so far.

Checked headlamp C/B

Installed this:
http://www.wildhorses4x4.com/product/Ni ... ht-Harness

Replaced my floor switch

Verified solid ground (ground wire next to passenger side headlamp).

I have a Centech harness installed.

Thanks.

Tom
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Post by DirtDonk » Tue Nov 14, 2017 1:19 am

Wow, no highs all this time, eh? I wonder if after all that it's the new(ish) relay harness?
But before we go down that road let's check some more ground aspects.

The only grounds associated with the headlights are right there behind each headlight into the core support. If you have painted the rig before installing the new harness, or there was any rust in the area under the terminals, you should remove the grounds from the studs, scrape/sand the area underneath, the re-attach the wires. If you're like me and hate future issues like I do, give a quick shot of spray paint over the tight connections. This way the bare metal that counts is in contact with the ring terminals, and any other that shows is now covered by paint. Almost rust-proof.

Next, did you add any grounds to your harness? This means more than just what you would normally have seen on an old Bronco. Of course there is the main battery cable ground from the negative terminal to the engine block. BUT (and this is the one that is left out most often) you also need a good connection directly from the battery to the body. This would usually be a 10ga wire right to the body. Typically the fender well under the starter relay. Use one of it's attaching screws to hold the new ground. Alternately you can use the original hole on the wheel well's inner side facing the exhaust manifold on the passenger side. You'll see a small-ish (1/4" maybe?) hole already punched into the metal.
After you ground the body, run a secondary jumper wire between the new body ground and the core support where the headlight grounds are.
Next add another auxiliary ground between the back of the engine and the firewall.
If you've a mind after all this, add a jumper ground between the engine and the frame, or the body and the frame. Or both. You can do it real clean and tidy down at the motor mount area and most people will hardly notice the extra wires.

I don't really know that this is the issue, or that you haven't done all that already. But it's good to get grounds out of the way first, before pulling your hair out tracking down a problem.

If that doesn't do anything, let's check out the high-beam section of the relay harness. We can talk about that in detail when you get back after the grounding party.
But in the meantime you can verify that your high/low switch on the floor is working. Assume you have a test light or a volt-meter? Check the output of the switch with the lights on. See if it's getting past the switch.

Good luck.
Oh, and sorry it took so long to get to this. I did not get a notification for once. Or if I did I forgot about it.

Paul
'71 Bronco - 302 4v
3.5" WH/Skyjacker Lift
33 x 11.50 x15 Thornbirds on 15x7 Enkei's
Kayline soft top
Hanson bumpers
Dual batteries, Large 1G alt.

WWW.WILDHORSES4X4.COM :mrgreen:

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Post by Puff Daddy » Wed Nov 15, 2017 11:46 am

Thanks for the advice. I've already checked the floor switch by using a jumper cable on the cannon plug. They didn't work even when the switch was isolated. I also replaced the dash headlight switch for good measure. I'll start doing a good cleaning on the grounds.

One thing I don't have that you just mentioned is a ground from the starter relay to the wheel well. I always thought that it was grounded through the base of the relay itself. Let me check all that and I'll get back with you.

Tom
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Post by DirtDonk » Wed Nov 15, 2017 11:57 am

The relay is indeed grounded through the base. It was the body itself I was worried about. There is always supposed to be an additional ground wire to the body. This gets left out of the equation more often than not, when an owner replaces the original ground wire.

What ford did was use a metal clamp to the body before the cable reached the engine block. What many people don't realize is that this "clamp" is not just for holding the wire in place, but in fact is soldered and/or crimped to the actual conductor to act as the body ground.
So when an aftermarket cable is used, it's up to the installer to add the ground back to the body somehow.
Often you see the ground cables with an additional 10ga pigtail and yellow butt-splice crimped to it's end. That's there for you to extend it to the body.

The problems also come up with headlights because over the years the core support gets less and less contact with the rest of the body and grounding bonds. This seems strange, since it's literally spot-welded to the fender skirts. But 50 years of rust and dirt and dust and layers of light corrosion block the path of electrons so you get a bad connection. Hence the need now, more than ever, to add multiple additional grounding points.
All the OE's including Ford have done that for decades, including while the Broncos were being built still. For some reason they decided to scrimp and save by leaving out some key wiring components that every other passenger car and it's brother did get. Heck, even the later seventies full-size trucks had multiple braided straps just bonding the cabs to the frame, and the body to the hood! Everything got a ground.

If your Bronco can't tolerate AM radio because of too much noise, we can probably thank lack of grounding at least in part.

Paul
'71 Bronco - 302 4v
3.5" WH/Skyjacker Lift
33 x 11.50 x15 Thornbirds on 15x7 Enkei's
Kayline soft top
Hanson bumpers
Dual batteries, Large 1G alt.

WWW.WILDHORSES4X4.COM :mrgreen:

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Post by DirtDonk » Wed Nov 15, 2017 11:58 am

While you're mucking about in the wiring, swap relays from one to the other. You know the low-beam relay is working, so try swapping it to the high size just to see if the trouble follows. If it does then you have a bad relay. If it doesn't change, then the fault is back in the wiring.
It could actually be in the harness itself.
Either the truck harness, or the headlight relay harness. Just gotta' narrow down the suspects.

Paul
'71 Bronco - 302 4v
3.5" WH/Skyjacker Lift
33 x 11.50 x15 Thornbirds on 15x7 Enkei's
Kayline soft top
Hanson bumpers
Dual batteries, Large 1G alt.

WWW.WILDHORSES4X4.COM :mrgreen:

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Post by Puff Daddy » Mon Nov 20, 2017 6:56 pm

DirtDonk wrote:While you're mucking about in the wiring, swap relays from one to the other. You know the low-beam relay is working, so try swapping it to the high size just to see if the trouble follows. If it does then you have a bad relay. If it doesn't change, then the fault is back in the wiring.
It could actually be in the harness itself.
Either the truck harness, or the headlight relay harness. Just gotta' narrow down the suspects.

Paul
Swapped relays, cleaned grounds with no luck. Before I got into creating extra grounds, I went out and bought a circuit tester...which I should have done in the first place. I started testing the circuits at the plugs using the plug grounds. All the plugs are getting power (using the plug grounds) to include plugs that attach to the light bulbs.

It seems weird to me, that the problem would be the headlamps. I find it unusual that the brights would be burned out at the same time on both headlamps. Is that strange to anybody else?
Tom

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Post by SHAWN » Mon Nov 20, 2017 7:19 pm

A 'circuit tester' will not put a load on the system... your volt meter may say everything is good, but if you run a load on it, poor connections or an 'open' may pop up as a result an inoperative lamp. If you ohm test the headlamp itself, is there continuity between the terminals of the bulb (when it is NOT plugged in!)? Try back-probing the headlamp connector with everything plugged in. Is this an intermittent problem,, low beams too? the system must be failing while testing for anything to show a fault.

wow, you sure did bring an oldy back up

...Hey Tom, glad to see you back checking this site.
8)

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Post by Puff Daddy » Tue Nov 21, 2017 12:26 am

SHAWN wrote:A 'circuit tester' will not put a load on the system... your volt meter may say everything is good, but if you run a load on it, poor connections or an 'open' may pop up as a result an inoperative lamp. If you ohm test the headlamp itself, is there continuity between the terminals of the bulb (when it is NOT plugged in!)? Try back-probing the headlamp connector with everything plugged in. Is this an intermittent problem,, low beams too? the system must be failing while testing for anything to show a fault.

wow, you sure did bring an oldy back up

...Hey Tom, glad to see you back checking this site.
8)

Shawn.
Thanks for the advice Shawn.

It's a constant problem...been going on for probably a year and a half. I just started tackling it in earnest now. The low beams work fine. I'll check the continuity of the bulbs in the morning.
Tom

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Post by Puff Daddy » Tue Nov 21, 2017 10:41 am

It turns out that the problem was the headlamps. Both brights were burned out. I installed a new lamp on one side just to double check my theory this morning and it was confirmed...it worked just fine. Still not sure how it happened. Thanks for all the input. I still learned a lot about trouble shooting the electrical system.
Tom

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DirtDonk
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Joined: Sun Jul 27, 2003 7:53 pm
Location: San Jose, CA
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Post by DirtDonk » Sun Dec 03, 2017 12:16 pm

It's not really unheard of. Not common of course, but not impossible. As you found out!
And they may not even have burned out at the same time either. They could have due to some voltage spike or another, but it could have happened to one and you may not have noticed right away. Then the next one went out and of course you would notice at that point no matter how often you used them.

Might even have been due to bouncing around over the years, but normally the filaments are pretty robust to handle all the heat and vibration normally. But you never know.
Are these sealed beams or H4's? New or old? Name brand or cheap copies?
Reason I ask is that a buddy had an H4 conversion and both (or at least one?) of the bulbs was defective right out of the box. I should say right away rather than right out of the box though, as I don't remember if he got any use out of them before failure or not. But new bulbs fixed it.

Glad you found it!

Paul
'71 Bronco - 302 4v
3.5" WH/Skyjacker Lift
33 x 11.50 x15 Thornbirds on 15x7 Enkei's
Kayline soft top
Hanson bumpers
Dual batteries, Large 1G alt.

WWW.WILDHORSES4X4.COM :mrgreen:

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Puff Daddy
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Posts: 514
Joined: Sat Dec 17, 2005 11:19 pm
Location: Tri Cities, WA

Post by Puff Daddy » Thu Dec 07, 2017 6:18 pm

They were old, and probably the cheapest I could buy 18 years ago, which was the last time I replaced them. (Cracked one in a fender bender. My winch bumper took a beating, but the Pontiac Sunbird was totaled). They're gone now, so I can't tell you for sure. Upgraded to the LEDs...wish I had done it long ago. The difference is literally like night and day.
Tom

Uncut '73, stock 302 w/Headers, Holley TA Carb, Centech Harness, Wildhorses 3.5 inch lift.

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