Turn Signal Issues

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eazyglide

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Eli
Truck Year
1976
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C10
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5.3 LM7
Having issues with turn signals not working on a 76 Chevy c10 with a new painless performance wiring harness and everything else working fine mostly. To start, I unplugged headlights (just troubleshooting at this point) and put the truck with the park lights on and walked around truck and all but the front right park/turn signal works and this one does nothing. Thinking the bulbs should be good I put the hazards on and everything works correctly including front right bulb that was in question. No issues with hazards on. Move on to reverse lights, these work correctly. Move to brake lights, these work correctly. Try turn signals again left nothing right nothing. Think to check turn flasher, I believe this is good as i can hear a clicking when i engage turn signal/stops when off and its new (only reasoning to say this). Checked over all fuses and none are bad. Checked power going to purple wire/turn signal switch and I think i remember 9-10v readings. Turn signal switch was new as well from autozone, was a 'matching' 8 wire switch that seems to work and have other reasoning to think its working as it should. Not sure where to go at this point, I had similar problems on last wiring harness but it had no hazards/front right turn/park light instead. I have now swapped out just about everything I can think of. Also have video of hazards. Any suggestions?
 

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projo198

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I just fought this on my '76 K10.

Looks like I get to be the first to say it, but check your grounds. I added a frame, motor, cab and bed ground strap and it fixed a lot of these issues.

If you are hearing clicking in the relay with turns and 4-ways there is something wrong with either the wiring, bulbs or light receptacle.

To be honest for my left rear turn I gave up and ran a whole new wire to it. Only one I couldn't get working.
 

eazyglide

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5.3 LM7
Grounds is only thing i assumed were good but ill go and sand every ground and add a few more to chassis-firewall and separate out some grounds I have stacked on eachother to new locations
 

Jgonick

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Incandescent or LED bulbs? With incandescent- Front park/turn lights use a two filament bulb. One filament will blink with turn signal the other filament is the the park light. (brake lights are also two filament bulbs) Hazard lights are fed by a different power source than turn signal lights. On the turn signal switch connector- brown feeds power to hazard lights and purple feeds power to turn signals.

Check the bulbs (a filament might be bad causing right park light not to be on) and check the connection at the turn signal switch (especially the purple wire). If the lights are flashing correctly with hazards that means the problem is -not getting power from purple wire. If checking connection and re-seating the connection at the turn signal switch doesn't fix the problem, re-check to confirm voltage on purple wire. Is there voltage on purple wire at turn signal switch connection? If no volts- double check fuse. What type of flasher? thermal or electric? If it is electric the terminals might be reversed. -or possibly bad flasher.

If you do have roughly 12 volts on purple wire-
Could possibly be a bad turn signal switch even though it is new.

I believe painless uses the same colors as original wiring
 
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ramirezsl

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tucson
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jorge
Truck Year
1982
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c10
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Having issues with turn signals not working on a 76 Chevy c10 with a new painless performance wiring harness and everything else working fine mostly. To start, I unplugged headlights (just troubleshooting at this point) and put the truck with the park lights on and walked around truck and all but the front right park/turn signal works and this one does nothing. Thinking the bulbs should be good I put the hazards on and everything works correctly including front right bulb that was in question. No issues with hazards on. Move on to reverse lights, these work correctly. Move to brake lights, these work correctly. Try turn signals again left nothing right nothing. Think to check turn flasher, I believe this is good as i can hear a clicking when i engage turn signal/stops when off and its new (only reasoning to say this). Checked over all fuses and none are bad. Checked power going to purple wire/turn signal switch and I think i remember 9-10v readings. Turn signal switch was new as well from autozone, was a 'matching' 8 wire switch that seems to work and have other reasoning to think its working as it should. Not sure where to go at this point, I had similar problems on last wiring harness but it had no hazards/front right turn/park light instead. I have now swapped out just about everything I can think of. Also have video of hazards. Any suggestions?
Having kinda same issue.. my dashboard right turn signal bulb won’t blink when I turn right I thought it might have been the bulb but it’s good, bought a new printed circuit and still no good. All my exterior lights work when turning right turn signal on except on the dashboard.. anyone had an idea where I can start to troubleshoot???
 

Jgonick

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my dashboard right turn signal bulb won’t blink when I turn right I thought it might have been the bulb but it’s good, bought a new printed circuit and still no good. All my exterior lights work
Does it work with hazard lights?
Double check to make sure the bulb is making good contact and use a voltmeter if possible to check for volts.
If you are not getting volts, since you just replaced the printed circuit, check the connector to the printed circuit- look for the dark blue wire and make sure it is making good contact.- It should be beside a light blue wire on the connector (you could also check for volts there on the dk blue wire) The dark blue wire runs to the bulkhead. At the bulkhead -inside the cab- there should be two wires- one comes from the turn signal switch the other is the one that runs to the printed circuit.
 

ramirezsl

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Does it work with hazard lights?
Double check to make sure the bulb is making good contact and use a voltmeter if possible to check for volts.
If you are not getting volts, since you just replaced the printed circuit, check the connector to the printed circuit- look for the dark blue wire and make sure it is making good contact.- It should be beside a light blue wire on the connector (you could also check for volts there on the dk blue wire) The dark blue wire runs to the bulkhead. At the bulkhead -inside the cab- there should be two wires- one comes from the turn signal switch the other is the one that runs to the printed circuit.
Thank you I will look into what you said and give it a shot… I will also turn the hazards on and see if they work…. If they do I will send a message your way… maybe you have another idea I can use….
 

ramirezsl

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Thank you I will look into what you said and give it a shot… I will also turn the hazards on and see if they work…. If they do I will send a message your way… maybe you have another idea I can use….
???? Any idea if it has a relay of where I can find a fuse???
 

Jgonick

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if your outside turn signals work correctly- it will not be a fuse or relay. The indicator light is on the same circuit as your outside turn signals. Your problem will be a bad ground or bad/ broke wire or connection

I highly doubt the indicator will work with your hazard lights- they use the same wire(s) as the turn signal circuit to go to the indicator lights and turn signals.

Confirming you are using an incandescent bulb in the right indicator.. IF you are using an LED bulb it might be in backward- a lot of LEDs will only allow electricity to flow in one direction. Take it out and turn in 180 degrees.
 
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