Stumped
 

I was helping my dad with the 1ton he just bought, we were trying to get the tail lights, turn signals and brake lights to work. The right turn signal is all that worked when you turned on the left turn signal, when he got it. When we got started the wiring was a mess, so we removed alot of wiring and tied into the factory wiring that is back there and got the left brake light and turn signal working but that's all that works back there. I checked the fuses, we changed the flasher (that's when the turn signal started to work) we found a broken wire up by the firewall and reconnected it and we still didn't have anything on the right.

Anyone have any ideas of what might be going on?

He is wanting to take this truck to pick up a parts truck for it next weekend so we are trying to get it fixed as soon as we can.

Re: Stumped
 

Have you looked at the wiring at the back,old trailer light wiring is a good place to start

Re: Stumped
 

Check all of the grounding wires and locations at the taillight assembly in question.

Check the receiver socket where each in question bulb is secured and make sure you have a clean area of contact minus any rust or condensation build up.

Like Powerdriver said, check any additional wiring added that is part of any trailering wiring.

From there, work your way back up to the fuse block, then to the interior wiring inline. Back tracing it from the easiest pointe to the most difficult is a start!

Re: Stumped
 

We replaced everthing from about the rear end back, just behind the rear end is where we tied into the factory harness. The factory wires are brown, green, yellow and light green. Brown is for park lights and tag light, green is ground, yellow is left turn and stop and light green is right turn and stop? Am I wrong?

Re: Stumped
 

dark green is right turn and stop
light green is backup
yellow is left turn and stop
brown tail lights
any black wires are ground

Re: Stumped
 

Ok, thank you.
Does it make any difference that it is an 80 with a 4spd?
I should have mentioned that in the beginning but I forgot.

Re: Stumped
 

nope gm has used that color code for years