[sneezingfox]

There has probably been a few threads on the issue of headlight switches for fox body mustangs. My headlights went out over a year ago and it has now started to bother me. To remedy the issue, I simply ran a wire to the headlight and mounted a fused toggle switch on the dash (high and low beams...) Now, it bothers me that I cannot turn my Factory switch to the on position and have my lights turn on, not to mention, the unsightly array of big silver toggles all over. I'm going to rectify the problem so that the headlights, fog lights, high and low work the way it did back when it was still on the showroom floor (or out on the lot; I was not there...) Feel free to add any input...

[ryans88gt]

Find a wiring diagram online, buy a multimeter or test light and trace the problem from the battery. The first place I would check is the fuse and look for 12V at the fuse box.

Most likely it is the switch itself, they aren't that hard to replace, you just have to take the gauge cover off. Have fun. My lights work fine, but if I turn my fog lights on my headlights will flicker off every once in awhile. I have never figured it out, so I just leave my fog lights off even though they work.

[sonicblue]

with after market fog lights and silver stars my headlight switch would get very hot and make the lights flicker. ran a relay and its good to go now.

[sneezingfox]

I figured it out. It was neither wiring nor the headlight switch. It was the multifunction switch aka wiper/turn signal switch. I put a relay on the low beam and it worked from the headlight switch. For the high beam, I put a relay also, but I had to put it on a toggle. The turn/wiper has no output. The plug was bit melted at one point. It has power going in, but neither low nor high comes out. But, the headlight switch, which controls parking lamps and fog lights, has an out put that goes to the turn/wiper switch. That's what I was able to use to get the headlights to work on the factory switch. To get the lights to stop flickering, I simply ran a power wire that was different from the headlight switch. The fogs still have a relay, but for some reason the low beams do not. So, when after market bulbs are put in, the switch does not have enough power to run both.

[nolife]

Ford fixed some issues with the Fox headlights around 1990 I believe. The main problem was the full current for the high/low/ and fog lights was going through the headlight switch and I believe the high/low beam switch as well. This caused the switch or the plug into the jack to overheat (this was not just a Mustang problem for Ford). Ford added a separate relay for the fog lights. If you catch this before either of the switches fail or melt too bad, you can add a separate relay for the fog lights somewhere in the engine compartment and power them from a separate fused line attached to the battery. My 91 GT is fine but I had this problem on my 88 GT. I would get the periodic flickering and dimming whenever the fog lights were on. Even with the Ford fix, the headlight and multi-function can still fail though but it will not fail as often.

For your problem, you worked around a failed multi-function switch. I agree though, Ford could have used relays for all of the lights and not had full power running through those switches. You would think they could have used cheaper switches and thinner wire and that would have made up the difference in the cost of a relay but I guess not.

[sneezingfox]

I always thought the fogs were on a relay. It was not until I looked at a Haynes manual that it shows the wires going straight from switches to bulbs. How did this even during the manufacter's warranty when the car were new?!

[nolife]

Well the factory warranty was only 12mon/12k miles until 92 so I guess it failed after that
My 88 Bronco II had the same exact multipin electrical connector on the headlight switch as the Mustang and it melted as well.
A little bit of corrosion in the connector and the problem gets bad real quick. This is why most places that sell alternators will highly suggest you replace the power connector on it at the same time even if it does not seem to be bad.

[ujslost]

Ford and their headlight and ignition switch problems! Your problems are not uncommon at all.

[sneezingfox]

Awesome. Now I don't feel so bad that most Ford owners experience the same thing. I was beginning to think it was the mechanic (me) and the driver (me)!!!