Turn Signal Issue That's Got Me Completely Stumped.

[Ellman605]

Well, I'm still lost. What I found last night was if I put on my hazards, they blink. Now, the second I press the brake pedal and the brake lights up, the hazards just light up. No flashing, just stay lit up.

[Myron]

While trying to figure all this out today I unplugged the taillight harness and now I have 12v at C156 connectors P and N :banana: . I'm guessing I have a socket or two burnt up back there. Ellman605, unplug your taillight harness and see if it still grounds out when you hit the brakes. If so, your problem is in the harness somewhere. If not, your problem is either in the switch or the wiring leading from it to the harness plug.

[Myron]

Long post ahead. I took my bulbs out and with a meter I get 12v at the plug. Put a bulb in and it won't light up. Redo the ground and still nothing. If I have a bulb in the socket I lose my voltage reading at C156 if it's plugged in. So what's the issue? I'm no electrician but I'm guessing it's ohms or amps? I run a hot straight from the battery to the taillight harness and viola, my lights are burning. Well, some of them anyways. Ok, so my taillight harness was trash. Someone had stuck it with a test light so many times I could see light through it. I fixed it the best I could and still nothing. The copper inside the wires was so corroded that they had turned a nasty shade of greenish-black. I pulled the taillight harness from one of my other trucks and now everything's fine back there. I plugged my hot in C156 and my lights burn, then the brake switch, then the fusebox. All good? I've got a glorified redneck connector fused in my fusebox making it work for now. Blinkers don't work anymore, but I'll look into that later. Whatever my ohm/amp drop is, it's before the fusebox. I'll update when I find the problem.

[Myron]

Ok so now my rear lights quit working on the driver's side. No running light, brake, or signal. This is strange considering that, with my old harness, I could not get the drivers side to work no matter what I tried. I assumed the sockets were bad, or the wires were corroded somewhere else down the line. I'm starting to think the wires running to that side may be grounded out somewhere? Does anyone know a way to check for this? I don't know much about wiring, but seeing as I'm constantly running into wiring problems, I need to understand it clearly if I'm going to get anywhere.

[mvusse]

If there is a short to ground, you will be lowing fuses. It is more likely the ground wire that powers those three bulbs is bad.

[Myron]

I have redone the ground behind the driver's taillight. Also checked continuity between it and the the sockets. Is there another ground thst would be relevant to my problem? Or could that one still be bad?