cml22

Hello, All

I'm new here, I've done some digging on my own but I haven't had any luck.

07 Tahoe LTZ - Turn Signals RH/LH work, Brakes RH/LH & 3rd light works. I do not have working tailights. I have checked the stop light fuses and relay under the hood and the fuses near the steering wheel, they seem to be fine. During the day when I manually turn on the running lamps - the license plate bulbs turn on so I assume everything should be in working order for the tail lights to turn on as well. I'm not sure what else to try before spending money to have it looked at.

Any thoughts ?

Thank You

EDIT: corrosion on wiring harness. Mechanic replaced wiring.

Yogi

cml22,
I had this same problem that began with my driver side tail lamp not working. Through time ( about a year) the problem found it's way over to my passenger side tail light and shortly after I had issues with my back up lights and turn signals. I did all the checks for fuses, breakers, weather pack connectors and grounds using a wiring schematic to locate all the possible shorts. I even pulled the fuse box off the fender well under the hood looking for a possible corrosion problem or a disconnect. That wasn't it. In short, I ended up taking it to a dealership. The did all the above and then got under the dash and into the firewall. Sure enough they found the problem. Between the firewall the wiring for my rear lighting had dry rotted within the wiring loom and created both a short and a break in the tail lights. Cost to repair without replacing the entire harness was just over $600 where the tech merely spliced the wires back together. They worked fine for about a month and I again have no tail lights. So, it's likely that the splice that was done was a low quality job.
If you have time and are flexible, do it yourself. Unless you have the cash to have the dealer do it for you. My vehicle is a 2008 Suburban.