2013 Tail Light short I can’t figure out.

[FireMaddox]

Trying to figure out this tail light short and looking for answers.

It’s a 2013 LS Tahoe. All the lights work fine except for the tail lights. I’ve checked bulbs, all the fuses, grounds, harness plugs, switch and replaced the trailer light relay and nothing. It’s also intermittent. Some days they come on. Some not. They will come on randomly while driving and then randomly shut off. Bumps in the road don’t seem to change that. I’m pulling my hair out and at a loss. I’ve crawled under it for hours checking the harness for breaks and so far nothing. Any suggestions?

 

[Doubeleive]

Trying to figure out this tail light short and looking for answers.

It’s a 2013 LS Tahoe. All the lights work fine except for the tail lights. I’ve checked bulbs, all the fuses, grounds, harness plugs, switch and replaced the trailer light relay and nothing. It’s also intermittent. Some days they come on. Some not. They will come on randomly while driving and then randomly shut off. Bumps in the road don’t seem to change that. I’m pulling my hair out and at a loss. I’ve crawled under it for hours checking the harness for breaks and so far nothing. Any suggestions?

can you clarify? brake lights? running lights? reverse lights? license plate lights? all of them?
one place you did not mention checking is the fuse box

 

[FireMaddox]

can you clarify? brake lights? running lights? reverse lights? license plate lights? all of them?
one place you did not mention checking is the fuse box

Running lights only. All other lights work.

 

[Doubeleive]

Running lights only. All other lights work.

That makes things easier, if you cannot find any break in the wiring then try adding a ground and see if that fixes it, if not then you know it is only the power wire.
adding a ground will not hurt anything and is very easy to do on the end pigtail right under the rear bumper, just go right to any easy ground location. such as a bumper mounting bolt 50% chance for a very easy fix.