i tapped into the factory trailer 7 pin wiring for both a goose neck trailer plug and for a 7 pin plug(less brake wire) for a slide in camper. the camper power wire is run to a battery isolator and the ground wire is run to the battery negative. the back up lights and outside running lights work ok on all plugs. i am having trouble with both the brake and turn signal lights on all plugs. all fuses, wire taps and new wires are ok. any ideas on what to check next???? :--)