Left Tail Light Has Some Issues

Maintenance/Repairs
1

Ok so I have a 99 GMC Suburban K1500.

The problem I’m having with my left tail light is that it…

  1. No Turn Signal
  2. When My Head Lights are off and the brake is pressed, the left brake light doesn’t work

I tried replacing the bulbs which was my first best guess. ( I did notice that one of the sockets looked burnt out ). Tested it out and still no turn signal. But the brake lights worked.

So a buddy of mine told me that it may be the turn signal flasher…So I went out and brought a replacement. Switched it out and still nothing. But in addition to this the brake lights would only come on unless I turn the head lights on.

Now I will say this…I just recently installed an amp and a subwoofer which required me to remove the dash so I could complete the wiring. Do you think that maybe I could have accidentally hit something like a wire or whatever causing me to have this issue? Also…before I replaced the flasher the turn signal and brake light DID work one early morning on my way to work but shortly afterwards it stopped.

I hope that this is an easy fix because it’s becoming very annoying and I really hate to drive like this. Any help or advice would be greatly appreciated!

Thanks!

2

See if the emergency flashers work ok with that light. If that works then the trouble is most likely with that switch. Cycling the switch a few times might clear the trouble. If the light dosen’t work with the emergency flashers on then you have a bad wire connection to that light somewhere. It may be at that switch.

3

I suspect that your multifunction switch is malfunctioning. One of the classic signs of a bad one is the brake lights not functioning and/or problems with the turn signals. It’s not really a DIY job to replace one because the airbag system is involved during the R&R process.

4

This

http://www.autozone.com/autozone/parts/Dorman-Tail-Light-Circuit-Board/1999-GMC-K1500-1-2ton-Sub-4WD//N-jd1wlZ9ckb9?itemIdentifier=89326_195359_4169

is the most common failure in the tail lights on that series of GM vehicles.

5

I learned something here today. A tail light circuit board and a multifunction switch? It’s a wonder that these vehicles have working tail lights at all.