I just wired up electric trailer brakes on my trailer, and they do not seem to be activating. All connections are soldered, (including ground), I used 14 gauge wire, all connections on the 7 way plug are good and in the right place. However, when I push on the brake pedal in the tow vehicle all I get from the brake controller is a dim red light. When I manually activate them i get no light at all. The brake controller works fine on my other trailer, so any idea what I have done wrong?