72 c10 turn signals not working
 

i'm restoring my c10 and i have working hazards parking lights and brake lights i've did some searching on here i don't have power at the purple wire at the horseshoe connector but i've got it at the flashing unit i've also changed all the bulbs to led i've also hooked a jumper wire to the purple wire and nothing changed not sure whats going anyone got any ideas

Re: 72 c10 turn signals not working
 

You need to change the flasher unit to one designed for LEDs.. Stock unit won't work...

Re: 72 c10 turn signals not working
 

i put one in that has a ground wire on it designed for leds

Re: 72 c10 turn signals not working
 

Before proceeding, be sure the LED flasher is well grounded...

The purple wire feeds voltage from the flasher unit to the turn signal switch for only the turn signals.. I've never installed LEDs on one of these old vehicles, so I'm not sure if the LED flasher unit is normally closed (N.C.) or not.. The stock flasher is N.C... This means that whenever the ignition is on, the purple wire is hot even if the turn signal switch is in the off position.. IF the LED flasher unit is normally open (N.O.), the purple wire will not be hot until a load is applied -- the turn signal is activated..

It sounds like you could have a bad flasher or open circuit (broken wire).. To check this, install the stock flasher and disconnect the "horse shoe" connector.. Turn on the ignition and check for voltage on the purple wire on the body harness side of the connector.. If you have voltage, the wiring is good, the LED flasher is bad...

{EDIT} LEDs are polarity sensitive.. You may need on of these:https://www.classicindustries.com/pr...ts/f90652.html

Re: 72 c10 turn signals not working
 

i've put the led flashing unit in the hazard location and it worked fine but if the purple wire is suppost to be hot with the key on why won't they work when i put a hot jumper on the purple wire i'm starting to get really frustrated

Re: 72 c10 turn signals not working
 

ok just went out and checked if i put the led flasher in the turn signal socket only one terminal is hot but if i take the hazard flasher that is the old style that came in the truck and put it in the turn signal socket the purple wire become hot but nothing happens what i'm confused about is why the led flasher will work in the hazard socket but not in the turn signal socket

Re: 72 c10 turn signals not working
 

You probably have a flasher that is dependent on polarity. Reverse the polarity using some test wires, perhaps with alligator clips or terminal ends.

Re: 72 c10 turn signals not working
 

i ordered one of those polarity reversal adapters from classic we'll see what happens

Re: 72 c10 turn signals not working
 

Not sure if you have tried. When I want to make a change (such as led) I always make sure the circuit is working with all stock components before I go chasing problems down. If it all works, try your new flasher with the old bulbs. It does not care. if it works then try the led. If problem arises reverse polarity on led.

Re: 72 c10 turn signals not working
 

reversing polarity worked thanks to all i was really confused on this one

Re: 72 c10 turn signals not working
 

Good deal, another problem solved. Thanks for letting us know the outcome.

Re: 72 c10 turn signals not working
 

The reverse polarity adapter or reversing polarity of led's?