'71 Mach 1 turn signal problem

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Heardatbeat

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Afternoon ya'll. I got a '71 Mach 1 with some turn signal issues. At first it was just a new flasher so I replaced them and they were good. Now my turn signals ain't working. I tried a different flasher thinking that was the issue but it did not address the problem. I replaced the turn signal switch for a new one and it still doesn't work. Checked my fuses and they are all fine. I checked my bulbs and none are burnt either. My hazards work fine and the turn signal lights on the inside of the car work when hazards are on. They flash on the outside as well but individual turn signals ain't working. Anyone got a similar problem that they have fixed?

 

73pony

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Had same problem. Got a new flasher. Worked for two days and out again. Got another flasher and haven’t had a problem since. You might have just got a bad flasher.

 

Heardatbeat

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Had same problem. Got a new flasher. Worked for two days and out again. Got another flasher and haven’t had a problem since. You might have just got a bad flasher.
I have tried two working flashers and also tried an electronic flasher. None of them got the turn signals to work.

 

73pony

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I was going to mention that the second one I got was an electronic one but i see you tried that already. When you checked the fuses did you use an ohm meter? We’re any of the sockets covered with coorosion?

 

Heardatbeat

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I was going to mention that the second one I got was an electronic one but i see you tried that already. When you checked the fuses did you use an ohm meter? We’re any of the sockets covered with coorosion?
I have not checked them with an ohm meter. Do I just put one clamp on one side and one on the other with the ignition on? The fuse box seems to be in pretty good condition. There is no corrosion on any of the contacts.

 

OzCoupe72

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Perhaps check you're getting power to the flasher, check for 12 volts at the white/purple wire on the flasher unit which comes from the fuse box, if nothing then it could be the fuse or a broken wire/dirty connection

If good then try for 12 volt on the light blue wire on the flasher unit when turn signal on, if nothing then it could be anything from the wire to the connections up to the switch

Seeing as you have replaced a few things it sounds more like a connection/wiring problem which would be best chased by a test light or multimeter

Good luck and perhaps Midlife will give you better ideas

 

72 H-code

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Hi,

If you can remove your steering wheel, I would suggest checking the plastic "cam" piece that actuates the flasher contact when you pull up or down on the turn signal lever.

I had replaced mine but forgot to properly orient the springs and it caused intermittent contact when the individual flashers were activated.

It is secured to the inside hub of the steering column with a rivet. Be careful when trying to pry it loose as it may break off the stem and cause you further problems.

Hope you can figure out your problem!

Marco



 

Heardatbeat

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Perhaps check you're getting power to the flasher, check for 12 volts at the white/purple wire on the flasher unit which comes from the fuse box, if nothing then it could be the fuse or a broken wire/dirty connection

If good then try for 12 volt on the light blue wire on the flasher unit when turn signal on, if nothing then it could be anything from the wire to the connections up to the switch

Seeing as you have replaced a few things it sounds more like a connection/wiring problem which would be best chased by a test light or multimeter

Good luck and perhaps Midlife will give you better ideas
I'll give that a shot tomorrow and see what it's doing .

 

Tucaz520

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Do you have the correct bulbs?

Single vs double element.

Dont assune what was in there is correct.

 

Heardatbeat

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Do you have the correct bulbs?

Single vs double element.  

Dont assune what was in there is correct.
I put the correct bulbs when I got the car. At first it was just a bad flasher. I replaced it and it got my turn signals working. Now thats the only thing that doesn't work. Hazards work but not individual turn signals .

 

midlife

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Do you have the correct bulbs?

Single vs double element.  

Dont assune what was in there is correct.
I put the correct bulbs when I got the car. At first it was just a bad flasher. I replaced it and it got my turn signals working. Now thats the only thing that doesn't work. Hazards work but not individual turn signals .
That almost always indicates a bad turn signal switch or a broken lead/bad flasher can from the turn signal flasher if brake lights work.  Here's a little tip: when installing a turn signal switch, put black electrical tape on the back side to cover the rivet heads.  Those rivets can touch metal and short everything out, ruining the TS switch.

 

Heardatbeat

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Do you have the correct bulbs?

Single vs double element.  

Dont assune what was in there is correct.
I put the correct bulbs when I got the car. At first it was just a bad flasher. I replaced it and it got my turn signals working. Now thats the only thing that doesn't work. Hazards work but not individual turn signals .
That almost always indicates a bad turn signal switch or a broken lead/bad flasher can from the turn signal flasher if brake lights work.  Here's a little tip: when installing a turn signal switch, put black electrical tape on the back side to cover the rivet heads.  Those rivets can touch metal and short everything out, ruining the TS switch.
Oh really? Man. That sucks. I was not aware of that. I just removed the old switch with a new one. So even if the hazards work I still could have shorted out the turn signal end of it? My wiring is a rats nest. The wires to the switch don't even match the wiring on the car. It would not surprise me if the previous owners replaced it with some cheap knockoff, the didn't take very good care of the car. I did an ohm test and I am only getting 12V to the two most right pins with it hold it as a frowning face  lollerz

 

midlife

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If the connector is wired correctly, only the yellow wire on the far right (top) should be 12V; the bottom wire is the outgoing horn and should show 0V when the connector is disconnected from the turn signal switch itself.

 

Don C

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Do your brake lights work? The brake light circuit runs through the turn signal switch. Also check the brake lights when the turn signal switch is switched to both sides.

 

Heardatbeat

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If the connector is wired correctly, only the yellow wire on the far right (top) should be 12V; the bottom wire is the outgoing horn and should show 0V when the connector is disconnected from the turn signal switch itself.
I'll have to post a photo of it. Although I may just pull the wiring and start the restoration project of mine.

 

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