My truck is displaying a message to "Service Trailer Brake System" on 2012 Chevrolet Silverado 2500 HD

And the trailer brakes do not work. Can you tell me what will fix this problem?

Asked by for the 2012 Chevrolet Silverado 2500 HD
should be under warranty at the dealer
Thanks
2 answers 1 comment
my 2007 done the same thing took a wire brush to the trailer hookup and sprayed pb blaster on it all works fine now