Turn signal issue

I just had this issue again after replacing my heater core. I did not remove any of my gauge bezel or switches from the main dash, but when I pulled the dash back it must have made a few connections loose. Turns out my issue was 2 things, first was the orange/yellow wire at the hazzard switch, it was a bit loose. Second the same wire where it plugs into the MFS on the column was slightly loose there as well.
 
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I've checked that. The MFS has a new connector and the hazard side is tight. I even trying jiggling everything while the turn signal was on. Thanks for the input. I'm willing to try anything. I need to get this on the road for my son.
 

jrichker

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SN Certified Technician

Mar 10, 200027,1792,70522473Dublin GAlowendmac.com
Jun 5, 2016
Multifunction turn signal switch:
Before you think about replacing the multifunction switch with one from the junkyard, here are some things to be aware of...

The problem is more common in GT models because they had fog lights 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:

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The following diagram is for 90-93model cars.

Turn signal switch wiring:

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This may help you. From another post on turn signal problems problem
 
What year is this?
I ran into a problem with the wrong mfs but if I remember right the plugs were different so this may be a moot point.
You do realize there are two flashers.

Its a 92 GT. I have checked to make sure I have the correct MFS . I also do realize there are 2 flashers. This is the craziest #$_@ I have had to deal with lately.
 
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I think to take it out of the equation I'd replace the multi function switch again and double check yourself by part number you have a 90-93 switch. I don't know what else it could be since you've tested the wiring as you say and you have power coming in at the right spots and if you jump the wire the correct light illuminates.

Double check your wiring again and ensure all is as it should be and you have power into the switch where you should and the connector is tight and the connector pins are solid. If all that checks out, try another switch as again I dont know what else it could be. Bad switch, bad wiring or bad connections, or a combination thereof.

Hang in there, don't give up, you'll figure it out. Electrical issues are and can be tough to figure out. If you get frustrated quit for the day and sleep on it and maybe something will come to you. It has for me in the past. Good luck
 
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Thanks. The new switch should be here by the weekend. If it doesn't work I will have to swallow my pride and take it somewhere. My son asked me how can you rebuild a car and not fix turn signals. That felt good.
 
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Thanks. The new switch should be here by the weekend. If it doesn't work I will have to swallow my pride and take it somewhere. My son asked me how can you rebuild a car and not fix turn signals. That felt good.

That's harsh... if my kid said that to me I'd do something like this to him. :D

iPjLv6z.jpg
 
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Without installing the mfs on to the column, plug it into the harness and probe the wires from the back to see if you have power coming out of the switch to the wires that go to the lights.
You say the turn signal lights come on when you move the lever but do not blink? Is that correct?
What happens when you turn the 4 way flashers on then hit the turn signals?
 
Without installing the mfs on to the column, plug it into the harness and probe the wires from the back to see if you have power coming out of the switch to the wires that go to the lights.
You say the turn signal lights come on when you move the lever but do not blink? Is that correct?
What happens when you turn the 4 way flashers on then hit the turn signals?
I'll check and let you know.
 
Without installing the mfs on to the column, plug it into the harness and probe the wires from the back to see if you have power coming out of the switch to the wires that go to the lights.
You say the turn signal lights come on when you move the lever but do not blink? Is that correct?
What happens when you turn the 4 way flashers on then hit the turn signals?


I believe he said he can jump the wires and the correct light will illuminate, switch disconnected.... but perhaps I read that incorrectly