First trip out with the new camper and my trailer brakes are acting up, the controller is not juicing the blue wire , matter of fact the green lights not glowing now at all. On the way down the green light glowed but the brakes barely felt like they were working. Push the slide on the controller and the light flickered red but no brakes. Now today I have nothing UNLESS I take my test light to ground and stick it in the blue wire near the controller then it starts glowing green and will power up blue wire. DOES THE CONTROLLER HAVE TO SEE A CERTAIN RESISTANCE FROM THE BLUE WIRE ? I've also checked all the grounds etc , all in good shape , trailer is 2 years old and been took care of , trailer brake controller is probably 15 years old. Help . Uh