Front Turn Signal Problem!

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74 Shortbed

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Ok, this is on my 74 beater, when I put the turn signals on(left or right)both sides blink but the rear ones work normal and so does the 4 ways and brake lights, I replaced the turn signal switch and both flashers, traced the wires from the switch all the way to the lights, did it 4 times and everything is good no bare wires or loose connections anywhere, followed the diagrams all the way and everything is right, sooo, obviously I missed something somewhere, anybody have an idea what I missed.. Thanks..

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theblindchicken

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Almost sounds like they're somehow swapped with or shorted to your hazard lights... Try turning the hazard switch on, maybe you'll have turn signals? :shrug:

Wait, do you mean that only both the front turn signals flash, but the rears in the tails operate just fine?
 

74propu

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Check the ground straps inside the sockets . If one is broke or missing the lights will hunt for a ground and flash all the lights.
 

74 Shortbed

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Almost sounds like they're somehow swapped with or shorted to your hazard lights... Try turning the hazard switch on, maybe you'll have turn signals? :shrug:

Wait, do you mean that only both the front turn signals flash, but the rears in the tails operate just fine?
That's the first thing I thought of but the hazards work fine even before I changed out the switch. Yeah just the fronts back works fine, figure it has to be in the front somewhere.:shrug:
 

74 Shortbed

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Check the ground straps inside the sockets . If one is broke or missing the lights will hunt for a ground and flash all the lights.
First thing I looked for is a bad ground and checked all the sockets and they all look fine, and all lights work. But I guess I could check them again, did it 4 times but what's one more time, lol, maybe I just didn't see it, I'll find out in a while when the sun come up.. Thanks.
 

Georgeb

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I noticed you mentioned changing a switch. Did you change the turn signal switch in the column?
Any change when the headlights are on?
What happens if you take out one bulb. Does the other side work correctly or not at all?
 

74 Shortbed

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Yep, changed the one in the column, nothing changes with the headlights on and I tried taking 1 bulb out at a time same thing, also took both bulbs out and the markers still blink. I've never had this happen before ever, strange but I'll go through it again one more time this morning, I had to have missed something somewhere, probably right in front of me that's why I missed it, lol..
 

Georgeb

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On the truck harness Lt Blu is the left front and Dk Blu is the right front. Check the continuity from the purple incoming power to the respective outputs to verify the switch is good. Do it with the switch unplugged as a short in the system will give you a faulty reading. Alternatly you could unplug then switch harness and feed +12vdc to either the light or dark blue wires and see if one or both sides light up. This will help narrow your search. If both still light up it is an issue other than the switch. If each lights seperatly look more closely at the switch......
 

74 Shortbed

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Well crap, wasted the whole morning on this crap, went through it all again and everything is good, checked the continuity and the new switch is good, guess I could feed power to each side and see what happens, I'll try that in the morning got a bunch of **** to do this afternoon.. Thanks for the help guys.
 

74 Shortbed

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Well, I unplugged the switch and fed power to one side at a time and both sides lit up, so It has to be a problem beyond the switch, time to double check everything again.
 

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Well, I think I found the problem at least part of it, I unplugged the firewall connector and cleaned all the contacts and plugged it back on and they work, didn't see anything wrong other than 40+ yrs of crud but who knows, so we'll see how long they work..
 

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