the brake light on top of my cab works. my turn signals work, and my running lights work but the 2 rear brake lights dont work. anybody have a solution? thanks

 

i had a similar problem in my 98 1/2 ton. i had power at the wire harness but not to bulb the taillight assembly had gone bad. i would check for power at the wire harness first then check the taillight assembly

 

also the light on my trailer brake compter thing that is mounted under my steering wheel isnt coming on anymore either.

 

i would still start out at the taillight assembly and wire harness, also in alot of GM pickups there is a wire harness to plug in trailer lights if not hard wired in already, try removing your trailer lights from this section see what happens or make sure you have power to that part of the harness. hope that helps