Head Light Question!!!!

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Usually is the headlight switch or the connector on the harness that connects to the headlight switch.
Sometimes the connections get loose and the connector melts.
 
Agreed. Check the headlight feed wire into the MF switch (it's red/yellow IIRC on the early aero foxes). While inspecting it, be sure it has power (when the headlight switch is in position 2).

Does your flash-to-pass function ok? If so, the issue should be before the MF switch.

Good luck.
 
Agreed. Check the headlight feed wire into the MF switch (it's red/yellow IIRC on the early aero foxes). While inspecting it, be sure it has power (when the headlight switch is in position 2).

Does your flash-to-pass function ok? If so, the issue should be before the MF switch.

Good luck.

Sorry But im not sure what "FLASH-TO-PASS" Function is but if its the flashers then yeah they work. before they stopped working u could move the blinker switch around and they would sometimes come on but now they dont.....:shrug:
 
Sorry But im not sure what "FLASH-TO-PASS" Function is but if its the flashers then yeah they work. before they stopped working u could move the blinker switch around and they would sometimes come on but now they dont.....:shrug:

When you pull back (towards you, as you sit in the driver's seat) on the turn-signal stalk, the high and low beams should illuminate as long as you keep the stalk pulled back.

If FTP functions ok, the wiring from the output of the MF switch [going to the lights] is ok.
 
FTP uses a different power source than the headlight switch.

I'd check the bulbs and for 12V and ground at the lights. If you don't have those, go back to the MF switch and test in/out voltage.
 
Before you think about replacing the multifunction switch switch with one from the junkyard, here's some things to be aware of...

The problem is more common in GT models because thay had foglights on the same power wiring as the headlights. Ford undersized the wire and that caused problems.

A word of caution about multifunction switches is in order here. The multifunction switch (high/low beam, wiper, turn signals) are different for different years. 87-98 will work in any 87-89 car. The 90-93 switches only work in 90-93 cars. You can't put an early model switch in a late model car, nor can you put a late model switch in an early car.

Supposedly you can move the pins around to make the switches work in model years that are different from the car the switch came out of. I cannot verify that and haven’t tried it .

Other possible problem sources for the turn signal & headlight malfunction are the ignition switch, multifunction switch and the plastic shell that holds the turn signal wiring connector pins.

The following diagram is for 87-89 model cars.

Turn signal switch wiring:
attachment.php
 
Resurrection!

Before I go poking and prodding at the wires (which I will anyways), on start up and every say, 5 minutes or more my wipers sweep once and repeat this cycle, along with my headlights not working which were replaced for some bright blue ones it looks like.

Sound like the MF? and no my FTP doesn't work with headlights switch clicked on or off.

Or do you guys, think the wiper issue is unrelated?
 
Resurrection!

Before I go poking and prodding at the wires (which I will anyways), on start up and every say, 5 minutes or more my wipers sweep once and repeat this cycle, along with my headlights not working which were replaced for some bright blue ones it looks like.

Sound like the MF? and no my FTP doesn't work with headlights switch clicked on or off.

Or do you guys, think the wiper issue is unrelated?
Your thinking is sound. The MF switch is where I'd start with the diagnostics for all the issues.
 
Years back I had the same problem with the MF. Those things are prone to overheating and melting. You could actually put your hand on the dash on top of the switch and is was hot. I followed this write up on how to wire the foglights and it worked like a charm.

http://www.corral.net/tech/maintenance/foglights.html

LRS also sells a replacement MFI harness if yours is toast.

http://www.latemodelrestoration.com/item/PE779/87-93-Mustang-Multi-Function-Switch-Repair-Harness


Funny how all of this stuff is coming back to me after 10 years of driving Cadillacs. Good to be back.
 
Well hello Mike, when'd you pick up your newest fox? and welcome back! Thanks for the links, I like to think of myself as a monkey with a multimeter when I don't have a write up to reference.

I actually don't have foglights (LX not GT :/) but it's the same issue I believe because of my aftermarket headlights that probably are drawing more power and don't have good voltage regulation.
 
That's my plan for my 95, to bring it back to factory qualitys, no point in modifiying an unresponsive car, just keep it nice.
Oh and I took a look at both the headlight switch and multifunction switch, on the mutlifunction switch a black/white wire was loose but it didn't fix the issue, popping it back in. I'll be testing for voltage at the wires today.
 
Okay okay, there's three cut wires in my engine bay near the battery, not a clue where they're suppose to go because there's no other wire to match it upto, there's a red/yellow wire (like the one in the back of the headlight switch but not nearly as thick), and then a black and what looks like green wire
I forgot to mention this, my sidemarkers and such all work, it's specfically, only my headlamsp that don't.
My MF and all connectors were intact, well there are three that move out of their housing easily but I pushed those back in to make contact.

I get good continuity from my headlights to the connector in the engine bay just passed the battery, but I can't really test from the connector to the headlight switch because there's not enough wire on my mulitmeter to reach.


picture of the three cut wires held up near the radiator, they run underneath the battery tray to the front of the car:
IMG_2174.JPG
 
I'm kind of confused, but have you tested those 3 wires for power while the headlights are turned on? Most factory wiring has a trace, so there would be two colors. Who knows if someone did something weird though (like adding aftermarket wiring to an OEM wire).

Was there 12V at the headlight connector(s) with the headlight switch on? The headlight wire colors are red/blk (right low beam) and lt grn/blk (left low beam).

If you have some spare wire or test leads, you can extend one of your meter leads (for testing from the MF switch to the headlight pigtail). You could always run your own wiring from the MF switch to the headlights if yours was hacked by someone.
 
Well they for whatever reason weren't relevant. Maybe one day i'll figure out why they're there, but the headlights weren't receiving power. We tested all the way to the headlights without issue. Finally at the MF switch on the back of a connector that had a red/black wire and red/yellow wire, we used a black one to jimmy rig a connection and the lights turned on. So it's not in the connectors but the assembly seems to have an issue.

The lights would basiclly worked when the red/yellow and red/black made connection at the MF switch assembly. Tomorrow if the junk yards are open im going to go and get a new one and plug and play. The lights should work then since we got them to work today.

Thanks though, I wouldn't of ever to of known to look at the MF if it wasn't for this thread and would've stopped at the headlight switch.

if any of you have been reading my repairs thread, I now have the horn working, can fix the lights, and today I got up to third gear (learning standard), all that's left is rims. Soooo close!
 
Nicely done. Foxes have the same issue with the headlight feed connections at the MF switch. There's a decent amount of current through those wires and connectors.

If you ever wanted to unburden the circuit (the MF switch, headlight switch, and all of that wiring), you could add a relay for the low beams (you could do one for the highs too, but most folks don't use highs that often).

Did the wiper thing get figured out too?
 
The wiper thing didn't get figured out, and the turn signals also didn't work. But hopefully that's all under the issue with the whole MF switch. Also the hazards did work, so assuming it's the same set up as the headlight switch leading to the MF it probably is the switch going.

The wipers sweep is a major issue because it isn't 'that' often so it doesn't bug me but still I hope it gets fixed when I replace the MF.

I'll look into adding a relay, save the money in the future and the trouble.