I bought a camper shell for my Sierra and it has a center brake light on it. The center brake light was wired into the left turn/brake light when it was installed. This means when I use the left turn signal the center light blinks. Looking at the trailer connector there isn't an independent brake light wire. The only thing I can figure is to run the wire up to the cab center brake light, but I can't find anything about the wiring for it. Any suggests would be appreciated.
