Headlights Blinking!

[75Bronc]

Okay well for a while now my headlights will randomly start blinking, the running lights always stay on, but the headlights will go out then come back on. So eventually i changed the switch. Then a couple months later it started happening again, i dont know what the problem is? i dont think its a ground wire of anything of that sort, can anyone help?!

 

[thegreatjustino]

Did you replace the dimmer switch on the floor at the same time as the headlight switch?

 

[75Bronc]

no but ive looked it over and messed with it and it doesnt seem to be the problem

 

[Viperwolf1]

Headlight relays will stop the cutout and make the headlights brighter if they cutout for a long period of time then come back on. If they're just flickering check the grounds on the core support.

 

[mattt]

Check your voltage when the Bronco is running. I was having the same problem, and a voltage regulator on it's way out seems to have been the culprit. Mine was pushing 15-16v with the engine running, and I think it was taxing the headlight switch.

 

[mustangtoby]

Headlight switch first, dimmer switch next. Niether of these cured mine. Check out the headlight upgrade (which cured mine). The halogen bulbs were pulling to much power through the old stock wires, causing the breaker in the switch to kick. Haven't had a single problem since wireing relays, cost about $15 in parts, headlights are super bright now. One of the best mods you can do, cheap too!

 

[Scoop]

X3 on the relay harness upgrade. Are you running halogen or H4 bulbs? If so the best fix is definately the headlihgt relay harness. It's a great upgrade even if you are not having the blinking problems!

 

[rekoj71]

My vote is still the dimmer (I know you said you looked it over but it aint too expensive). Mine started blinking off like that too (hate intermittent electrical issues) finnally figured out that if I kicked my dimmer the lights would usually come back on. Had the same problem 3 times and all 3 times that fixed it.

 

[Broncobowsher]

My vote is the new headlight switch is bad.

 

[75Bronc]

mustangtoby, what was your sugestion on the headlight upgrade? what exactly did you buy and replace?

 

[daddyg]

Another vote for the headlight switch.. Mine acted the same way and I replaced the switch and it fixed the problem. Replacing your switch worked the first time for a little while, maybe you got a bad switch. It should be warranted for at least a year..

 

[BRONCOchild]

maybe there's an issue with your alternator!

 

[Cooter_76]

Here's a thread that discusses the relay upgrade.
RJM sells a plug & play harness as well.
I did the relay upgrade and used the headlights that Broncos n VW's mentions in this thread.
Lights are bright now and no surprise blackouts. Best bang-for-the-buck upgrade I've done!

 

[76MaBronco]

I had the same problem years ago and it ended up being a heat buildup under the dash and making the circuit breaker in the switch pop, reset, pop, reset...always worked when cold, always popped when hot...

But that was 20 years ago...My memory might be wrong...

 

[75Bronc]

okay so i replaced both my dimmer switch and my headlight switch today, and if anything its just worse! Im getting frustrated, now i need to change the relay? Which relay do i buy, and where do i get it?

 

[75Bronc]

which relay do the headlights run off? im lost...

 

[Viperwolf1]

The stock harness doesn't use a relay. I built my own relay harness but you can get them from a few places.

http://www.wildhorses4x4.com/product/Illuminator_Headlight_Harness/Performance_Lights

Painless may have a plug-in relay harness too.

 

[DirtDonk]

The stock "relay" referred to earlier is probably the headlight switches internal circuit breaker.
The aftermarket relay setups they're talking about take the load off of the stock headlight switch and allow power to travel more efficiently to the lights. Usually ending up with brighter headlights as well as a longer-lasting switch.
Try unplugging one headlight at a time and see if the problem persists. If it's doing it with a new switch, you've either got a defective switch (seen it happen) or a circuit that's pulling too much amperage (almost a short circuit) between the switch and the lights.
But unplug one, then swap to the other, headlight and see what happens.

Paul