Integrated Brake Controller

I am the original poster. I took my truck into the dealer this morning. Using the factory installed 7 pin plug on the bumper of the truck, they could not find anything wrong with the brake controller. There were no error codes and they said that the controller was giving output when the brake pedal was depressed. I always use the plug in the bed of the truck that was installed when I had the hitch installed. The dealer would not check that plug since they didn't install it. I never thought of trying the plug on the bumper since I always have a adaptor for my utility trailer plugged into it. Since the plug in the bed of the truck is in parallel with the factory installed plug, you would think it should work also unless somehow that plug has something broken inside. I am going to pick up my trailer in the morning so I will find out if I have a bad plug. My gut says that something else is wrong but I hope my gut feeling is wrong.