Tail Lights Not Working

[cwdavis]

Any help would be great.

The issue is I have no tail lights. Last weekend the passenger side was working. I had blinker, hazard, backup, and tail light. The driver side had nothing. I had about 3 volts getting to the back. After trouble shooting I could not find the cause. But the passenger side still worked fine.
I tried working on it this weekend and found both sides were not working. I now get nothing. Everything in the front works fine.

Thank you

[57larry]

check your grounds

[davischevy]

Check the plug in connections in the harness. Sounds like one may have worked its way loose.

As mentioned, grounds are always suspect too.

[71swb4x4]

I would start with the grounds and then on to the harness.

[berch 69GMC]

Check the thread 68 wiring problem. Vettevet walked me through a solution for my issue. Perhaps some of the diagnosis will help you.

[muley]

Agree with the ground. Check that first. Mine was going out intermittantly at first, then more frequently. I would start it up in the morning to warm up, and have no lights. Jump up on the rear bumper and bounce the pickup, there they are! So I made ground straps for,
Motor to the cab
Motor to the frame
Cab to the bed
and at the back end, I went back to bed to the frame.
Now works like a charm.

[Mr Chevorlet]

I would unplug the harness at the back of the truck on the frame and use a test light there and see if all circuits work there, if so its a ground at the tail lights and if all the circuits do not work at the plug at the back, work your way to the signal selector or that area and make sure no wires are broke or almost broke along the frame.

[rotor_kin]

First post here but I just had this issue the other day so I though I might chime in. My taillights were working intermittently and it was a pain to figure out. Turns out it was the turn signal switch in the steering column. Years and years of gunk had worked their way in and all of the contacts were half dirt. I took the springs out and sprayed loads of contact cleaner in there and worked the turn signal selector back and forth until everything moved smoothly and the contacts were shiny. Put it back together and everything came back as should.

Hope this helps!

[cwdavis]

Thank you for the advise. I have not had a chance to apply it. I plain on doing it this weekend. So I will let you know what I find. Again thank you.

[cwdavis]

Okay I was able to get the taillights to work. I it was a ground issue. I cleaned the ground on the rear side markers.

However now the issue is with the driver side. I have no brake, blinker, or hazard light. I would look at the column if not for the brake light. I mean the column does not control the brake. Does it? Any ideas?

Again thank you for the help thus far.

[davischevy]

Originally Posted by cwdavis

Okay I was able to get the taillights to work. I it was a ground issue. I cleaned the ground on the rear side markers.

However now the issue is with the driver side. I have no brake, blinker, or hazard light. I would look at the column if not for the brake light. I mean the column does not control the brake. Does it? Any ideas?

Again thank you for the help thus far.

Did you check the bulb? Did you check for power inside the bulb socket?

[cwdavis]

I checked the side marker bulbs. As for the Brake, Hazard, and blinker. The light is LED. I switched it the passenger side and verified it worked. The socket is getting power. This is what has me confused.

[rotor_kin]

The power for the brake lights does indeed go through the column/turn signal switch. Its kind of weird but I am almost positive thats where your problem is at. You should just need to remove the steering wheel and hub, and then just clean the hell out of everything you see. I always disconnect the battery so that the horn doesn't go crazy and piss off the neighbors

Hope this helps

[northerngmc]

Originally Posted by cwdavis

Okay I was able to get the taillights to work. I it was a ground issue. I cleaned the ground on the rear side markers.

However now the issue is with the driver side. I have no brake, blinker, or hazard light. I would look at the column if not for the brake light. I mean the column does not control the brake. Does it? Any ideas?

Again thank you for the help thus far.

Do you have ground straps on this truck?

There should be several. I had a 69 GMC that I was chasing similar electrical problems. I found there was not a ground strap from the box to the frame. I would suggest looking for grounds straps and if not run a short piece of wire from the box to the frame.