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Help 89 lx headlight trouble

89lxfox

Guest
My brights cut off and on after 30 mins of use, replaced headlight and combo switch was fine for a week now acting up again. No burned connectors or wires and bright indicater goes out also so that eliminates bulbs and wiring after switch i made a video of it acting up i will try to post it soon, but when they go off i go back to dims and when they come back on after 10 seconds the dims stay on fine but turn brights back on and wait it will start cutting on and off again :(
 
Just a Thought, Have you upgraded to higher watt lamps recently? It sounds like their could be an overload somewhere after they have been turned on for a while.
Just thinking out loud, but after I had changed out the 55 watt low beam lamps on my 82 G.T. four lamp system to aftermarket Hella 100watt low beam lamps, my driving lights/fog lights did the same cut out thing after a few minutes on. Apparently Ford had built in protection in the wiring as to not fry the wires if a higher wattage lamp was used. I guess I was lucky my wiring or car didn't go up in a cloud of smoke. I had to install 2 separate relays on each side of the H/L wiring under the hood, then wired them both directly to the fuse side of the H/L switch under dash to keep the higher load off the switch. Just my 2 cents. I realize your 89 has different wiring but maybe the same applies.

By the way for anyone who cares, Those 100 watt Hella's really helped with night driving in the mountains. They could burn the paint off of someones deck lid if I got too close. (I digress). I did have to re-adjust them down 2 notches with my Hoppy light adjuster kit as not to be flashed by oncoming traffic. The fluting cut-off angle designed into the lamps were great. I never hit an animal or anyone else in my years of night time mountain driving and never blinded on-coming traffic. The main thing was I could see well beyond what I needed at speed with them.

I do recommend them though if you do a lot of night driving. Love those european lights!

Didn't mean to get off track down memory lane, and no I don't work for Hella, Just wondering if you stepped up to higher wattage lamps..
 

89lxfox

Guest
Nope stock headlamps im about to warranty the combo switch at oreillys and stick another one in as soon as i get off work, the problem was gone for a week after i put the first one in and it will give me a chance to look over the wiring again for any loose or burned connections
 
Hmmm? If there stock Lights then there is a problem. Sorry I couldn't be of help. Just past experience info I thought would share. Maybe is the switch. Would be interested what the cause was. Good luck on the troubleshooting.
 

89lxfox

Guest
Thanks but i just put the new combo switch in and its been running for 30 mins, hoping this gets it even though fords wiring design on these cars is terrible. I just fixed the turn signals two weeks ago the orange wire came out of the hazard connector, the reason i replaced the combo switch was because the turn signals, wipers, and brights started acting up within a month of each other, turn signals and wipers fixed now just need to get rid of this brights issue
 

Blown347

Moderator
Staff member
I have sort of a similar problem. I haven't torn into it, but when I turn on my fog lights on, then headlights will cut out sometimes. As long as the fog lights are off, there's no problem. I'm no electrical expert, but I can follow directions.

Any thoughts?
 
I have sort of a similar problem. I haven't torn into it, but when I turn on my fog lights on, then headlights will cut out sometimes. As long as the fog lights are off, there's no problem. I'm no electrical expert, but I can follow directions.

Any thoughts?
I Left the 4 original stock headlights in place on the 80 cobra years ago and tried just changing to the brighter aftermarket 100 watt Lamps (bulbs) in the original driving light housings and they did the exact same thing. They kept cutting out. (flickering) The rheostat appeared to be overloading from the higher wattage bulbs I put it. I would have had to add relays to the driving lights in order to keep them. Might check to see if someone upgraded the driving light bulbs?
My 2 Cents.
 

89lxfox

Guest
I have tested it for two weeks now mine was the headlight switch i got a borg warner from oreilly's part number s2071 no more problems mine is also an lx so no fog lights on the switch
 
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