Tail Lights/Parking Lamps Don't Work

[paulyt]

Hello,

I have a 2007 Yukon Denali with 226,000+ miles on it. I just had to replace my original alternator a few weeks ago. After replacing the alternator, I noticed my parking lamps/tail lights don't work at all. Even with the headlights on the tail lights still remain off. I have checked the fuses and relay and they are fine. Does anyone have any idea what could be causing this problem?

Before I had my alternator replaced I was having a different issue with my parking lights, every time it rained or I washed my car the parking lights would stay on constantly. The only fix I found for this was to pull the fuses or relay. Here is a thread about it here: http://www.tahoeyukonforum.com/threads/parking-lights-wont-turn-off.96918/ Not sure if they are related but I figured I should mention it.

Thank you in advance! Any help would be greatly appreciated!

-Paul

 

[jmm121783]

do you have the tow package? a trailer hitch? If so, please check the junction from the body harness to the trailer hitch, this can easily corrode and short/create problems with the taillights. I had a really weird issue with my truck where the rear right "running lights" (lights that stay on in the dark so that people can see you when you're not pressing/applying the brakes or turn signals). To fix this problem the only thing I found that would work 100% that didn't involve 10+ hours of troubleshooting was to run a jumper wire from the working drivers side tail to the other non functioning tail light. Most of the times it is that trailer harness junction that gets rotted out, especially if your car is in the Northern parts of the country.