I just picked up my 2021 Chevrolet Express 3500 Extended Passenger. I had the tow hitch/wiring factory installed. I located 4 wires under the dash by the brake peddle that were taped off. I connected the brake controller to them and I have no power to the brake controller. I don’t see any fuse ports that say specifically for a brake controller, only trailer lights, which are all filled with good fuses. Can anyone guide me in the right direction?