Turn signal issue.

sc91gt

Registered User
Hello, I've tried the seach in this forum, but it will only search turn, and signal separately. Which only comes up with a billion threads to no where. So, can anybody tell me why the turn signal will work fine sometimes, sometimes not at all, sometimes sporadicaly. Any ideas would be great. Thanks,Shawn.
 
Your SC has fog lights right? Does it have auto dim? It is the multifunction switch. It is that whole assy with your wipers, low/high beam, hazards and turn signals. It was a TSB or recall on most our cars. Make sure the pigtail isn't melted when you change it. If it is put a new one on. Buy Wells, duralast or OEM. If you buy from AM or partstrain you will get bad ones. I know I put two bad brand new ones in before I bought a decent one.
 
Your SC has fog lights right? Does it have auto dim? It is the multifunction switch. It is that whole assy with your wipers, low/high beam, hazards and turn signals. It was a TSB or recall on most our cars. Make sure the pigtail isn't melted when you change it. If it is put a new one on. Buy Wells, duralast or OEM. If you buy from AM or partstrain you will get bad ones. I know I put two bad brand new ones in before I bought a decent one.

And also check the ignition switch on the column. They come apart and can cause intermittent turn signal malfunction....12.00 part...
 
Standard headlight switch, new and good, newer good headlight harness, foglights are not working. But have not tried them since headlight/dashlight fix. Put in a used junkyard multifunction switch that actually clicks when you hit it. I know, its a used part too... The harness' looked good when I switched it. ? Thanks
Your SC has fog lights right? Does it have auto dim? It is the multifunction switch. It is that whole assy with your wipers, low/high beam, hazards and turn signals. It was a TSB or recall on most our cars. Make sure the pigtail isn't melted when you change it. If it is put a new one on. Buy Wells, duralast or OEM. If you buy from AM or partstrain you will get bad ones. I know I put two bad brand new ones in before I bought a decent one.
 
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hold up, you swapped all three at once. I always swap 1 part at a time so if I have a problem I can troubleshoot it. Now you have no foglights and you could have three culprits. Most likely your standard headlight switch was not for a car with foglights. Correct me if I'm wrong folks.
 
Sorry for the confusion.

I first changed the burnt headlight harness and turnsignal stalk. Then I tried a different headlight switch. Since the new headlight switch didn't cure the dashlights I put the motorcraft one back in, and the one i bought in the glovebox. The dashlight culprit was the po's hack job on the stereo wiring. So now the lights work great but the turnsignal is still intermittant. It seems to happen mostly with the headlights on. ? As for the fog lights they did not work when I bought the car and still don't. I have not messed with them yet. Was hoping headlight switch would get them working. Going to check for voltage, but not a high priority yet. Does this help? Thanks for the imput.
hold up, you swapped all three at once. I always swap 1 part at a time so if I have a problem I can troubleshoot it. Now you have no foglights and you could have three culprits. Most likely your standard headlight switch was not for a car with foglights. Correct me if I'm wrong folks.
 
How did you fix the PO's hack job on the wiring harness.....

Are you sure you installed the correct MFS.....

There are 3 different MFS...
 
I'd definately check the ignition switch. They ALL will wear out after awhile. Don't put it off either. If you have an 89-91?, you could lose your brakes!! :eek:

I lost turn signals the other on my car...everything else worked fine (I have a conventional brake swap). Turnsignals worked the next day....the following day, the car wouldn't start. :rolleyes: I'm sure the ignition switch is the problem...it was looking a little loose when I had the dash apart, but I was trying to get my car finished for the shootout. :rolleyes:

On another SC, I lost turnsignals and brakes at the same time...on an exit ramp!!! Changing the ignition switch fixed it.

Ed - what are the three different MFS's? I only knew of two. :confused::eek:
 
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Wiring harness for headlights, I cut the burnt one out and spliced in a good one. For the stereo I found a couple of wires under the plastic touching metal with no insulation or spotty tape job. Deck looks to have been cut out. So I covered all open wires and bundled them nicely till I get a deck. As for the MFS? It looked the same as mine and had all the same pins in the same locations. And the turn signals do the same intermitant no work thing. This morning driving home with the lights on The signals worked fine. Yesterday eve only once in awhile. I have a new ignition switch, just need to get torx bit.
How did you fix the PO's hack job on the wiring harness.....

Are you sure you installed the correct MFS.....

There are 3 different MFS...
 
Ignition switch??

Well, I put a new BWD ignition switch in and the signals wouldn't work at all? Also It died and would turn over fast, faster than normal but would die as soon as you let off the key. Put the ford switch back in and fired up worked fine. Anyone had issues with oreilly's BWD brand stuff before? That is the third suspect Item I've got for this car, headlight switch,dis module, and ignition switch. In all situations I put the ford part back in.
 
I don't know if you checked this in regards to your turn signals, but my relay had a bad solder joint that just went out, and all I did was resolder it and they started working again. My turn signals would do the same thing yours were doing.
 
relay?

Where is that relay located? Thanks, Shawn.
I don't know if you checked this in regards to your turn signals, but my relay had a bad solder joint that just went out, and all I did was resolder it and they started working again. My turn signals would do the same thing yours were doing.
 
Where is that relay located? Thanks, Shawn.

Its under the dash board, on the driver's side, toward center console. Its a large black relay. Biggest one in there, and its mounted on the flat part under the dash, not on the vertical part under the dash thats on the transmission tunnel.
 
OOPs?

Well, when I installed the previous ignition switch it must not have been in the ''run'' position like it was supposed to. When I connected the battery cable all the instrument lights came on as well as the abs solenoid and the the chime for when you leave keys in ignition/lights but instead of dinging it was constant. The ignition cylinder was almost stuck. Worked the cylinder till it slotted the pin in the switch and the car would turn over, but faster than normal but no start. So I disconnected the bat took out the new switch, made sure the ford switch was in the right position and re-installed it. Now it starts up and runs fine but no sigals or reverse lights. Fuses are good. Pushed the hazards and all four corners light and blink like they are supposed to. Have no idea what i could have screwed up.? Any ideas? Please.:(
 
Well I don't know about the reverse lights but my hazards worked fine before I resoldered the relay pin, but my signals didn't.
 
Given the poor wiring set-up for the lights i'm of the opinion putting in a set of auxiliary relays to run the headlights and fog lamps should be a must do on every ones list.

Your lights will be brighter and you won't ever have to replace your MFS and headlight switch again.

Sean
 
Stumped!

Since my previous ignition switch snafu my signals went from working most of the time to not at all and reverse lights no longer work. I tried again swapping switches and turn signal/mfs today. Nothing. Also rechecked all fuses since manual says signal flasher and reverse lights are on the same one and they are all good. The signal relay under the dash clicks and fires the signals at all four corners when hazards are on, but does nothing when I hit the turn signal individually. Does anybody know what can cause this? It sucks to not be able to drive my car for something so simple. Thanks for all the previous info. I am going to go check the fuse slot for voltage. Fuse slot for the flasher/reverse lights has 11.72 volts with ignition on. ?
 
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Mfs

By luck I think my Junkyard mfs switch has the same letters.
There are white letters on the bottom of the MFS that end with AAD, BAD, and CAD.....

AFAIK, they are not interchangeable....:rolleyes:
 

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