Brake controller

my fathers tacoma 04 model he was towing the boat and the brake lights dont work on the trailer the lights work when he turns on the lights and when he turns on the emergency flashers and we checked the fuses on the trailer controller and they are all good but still no brake light on the trailer but the brakelights are working on the truck so is it the trailer controller not working it is the one installed by toyota as part of the towing package and if you think it is dieing where do i find a cheap one

 

You probably have a rusted/broken male pin in your electrical adapter. PM maverick491 as he will be better able to help. He's our resident tow Nazi.