Electric brakes on my trailer do not work?

I had the switch installed by pro. When I hook up the trailer to the truck I need to use a aligater clip with wire from truck to trailer to make the tariler lights work. Thats one problem the second is the brakes there all new and I just ajusted them but still do not work I get a clicking noise when I hit the switch in the truck but the tires do not stop the trailer. All the wireing looks good. Can it be the ground or somthing with the brakes. Thanks