Now I am gettin Grim! The market lights on the dually fenders and the 3 on the tail gate I cant get to work. All new LED lights, All new Pig tails from the dealer because the old ones were corroded. Is there a fuse for these lights, or any other plugs I can check under the truck???? Any ideas are appreciated.

 

LED lights are polarity sensitive. Any chance you have the wires reversed? Hooking them up backwards won't hurt them. They just won't light.

 

Tried switching them around. Still dont work!

 

LED'S draw less power than filament bulbs do. You may need a in-line load equalizer. For flashers and brakes, sometimes a heavy duty relay is required.
my.02

Fruitman