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headlights went out while driving

drajj5

Full Member
Joined
Sep 5, 2006
Messages
167
Loc.
Ellijay, GA
On my way to work early yesterday before daybreak, the lights on the bronco kicked off....Dark as hell and could not see anything I applied the brake and held the steering as straight as possible. Fortunatly I was able to (feel) the side if the road listining for the Burp-Burp- that was eminating from the tires as I eased off the road. Scared the hell out of me.

I finally was able to get the lights working again by 'pumping the light switch' in and out. Never did it fail, during the 25 miles or so left of night driving. I did open the windows and let the cool air calm my nerves before arriving at work.

I had light problems before (blew them both out) due to a faulty Voltage Regulator. I replaced both the VR and headlights with some new halogens. Could it be that those new halogens pull too much current for the older wiring harness?
 

Apogee

Contributor
Bronco Guru
Joined
Nov 26, 2005
Messages
6,035
Yes, the halogens are running too much current through the switch, tripping the thermal overload and cutting out the lights. When it cools off, the lights work again. Very common problem and easy fix with a headlight relay wiring harness.
 

asinor

Bronco Guru
Joined
May 13, 2011
Messages
1,396
Loc.
Tulsa, OK
I had light problems before (blew them both out) due to a faulty Voltage Regulator. I replaced both the VR and headlights with some new halogens. Could it be that those new halogens pull too much current for the older wiring harness?

I've had this happen on multiple occasions in another vehicle, even got a ticket for driving with my brights on because the low beams blew out 5 minutes earlier. Halogens are not very tolerant of voltage spikes.

My EB has also had the phantom headlight switch problem occasionally. Pull over, shut it off, turn the lights on and off a few time, start it up, turn them on. Never am able to get them working again without shutting it off first so it may be a VR or relay issue.
 

Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,322
The stock headlight switches have a common problem. They have internal thermal circuit breakers that tend to open when the high beams are used for extended periods of time. The fix is to install a set of headlight relays. They will also provide brighter headlights. Most vendors have them or you can make your own.
 

ryansbronco

Bronco Guru
Joined
Mar 6, 2002
Messages
1,160
Loc.
The place of bronco
the wires should be fine for the H bulbs, you just wont get full power to them
I think your headlight switch went out. I have ran across a few crappy ones lately. Try to find a standard motor products switch. I've had good luck with them.
You can build your own relay harness to make use of the H bulbs. All then ends and relay holders can be got from napa. I should have done it this way. The vendors kits are fine. No vendor bashing here, but what you get you can google how to do it and build it for half the cost.
 

Scoop

Contributor
Have Bronco, Will Travel
Joined
Feb 1, 2006
Messages
10,604
Loc.
Cuchara, CO
Had the same thing happen to me after a long day on a dusty trail - and I already have the headlight harness! Seems it was dust in the dimmer switch and the first time I hit the highbeams on my way back my lights went out! And I was on a windy mountain road in Colorado! Pulled over and pumped the dimmer swtich a bunch of times until they came back on and then didn't touch the switch again. It's never happened again.

That said lthe headlight harness is a great upgrade and should be done with halogens.
 

JLBachs

Full Member
Joined
Feb 4, 2011
Messages
333
Not to Hijack, but this was happening to me a lot. I replaced the dimmer and the light switch. I would push in and pull out the light switch and I "thought" that was making the lights come back on until one night when nothing helped. I got looking around and found out that one of my turn signal sockets was coming loose from where it was stamped into its housing - I could move it and make the headlights come on and go off. I temporarily pulled tension on it with a piece of baling wire (it's still there) and have been meaning to tack it with the mig sometime. The extra strain of completing this almost-open circuit must have been tripping that internal circuit breaker - shot in the dark but may be something to check
 
OP
OP
drajj5

drajj5

Full Member
Joined
Sep 5, 2006
Messages
167
Loc.
Ellijay, GA
That link is broken....could you post it again.


I did replace the headlight switch not to long ago(dimmer spring/resistor broke) with an aftermarket switch. I was thinking that the new switch is bad....

However, I would love to fix this problem " Relays are the solution"- so survey says.......Anyone care to share how this is done?
 

Bronco Junkie

So Cal Broncos
Joined
Feb 29, 2012
Messages
3,233
Also, try to avoid Chinese relays. I went through 3 of them (they blew at first try) before I went looking for others. Found some made in Japan and they are working superbly!
 

Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,322
Not to Hijack, but this was happening to me a lot. I replaced the dimmer and the light switch. I would push in and pull out the light switch and I "thought" that was making the lights come back on until one night when nothing helped. I got looking around and found out that one of my turn signal sockets was coming loose from where it was stamped into its housing - I could move it and make the headlights come on and go off. I temporarily pulled tension on it with a piece of baling wire (it's still there) and have been meaning to tack it with the mig sometime. The extra strain of completing this almost-open circuit must have been tripping that internal circuit breaker - shot in the dark but may be something to check

More likely 1 of the wires was shorting to ground in that was putting the extra load on the headlight switch and breaker.
 
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