Long story boring. Had a brake issue, ended up being the brake pads came off of shoe causing drag and heating up the hub. It wasn't as bad as it could have been. Took it all apart and brake pads fell out. I replaced with a new backing plate. In cutting the wires, I cut too many and had trouble reconnecting to same wires. I had very little response to hand brake on dash. I had a mechanic look at it and he connected the wires properly. I had full engagement upon using gain control switch but none with brake pedal. Mechanic said it may be on the truck end. I drove it home the next morning and I had no brakes, even after I saw that they were working with the gain control switch. The 'service trailer braking system' light came on yesterday as it should and did the same this morning. I was ensured that all wires have been properly hooked up. I have a 2019 Chevy Colorado, with factory installed trailering package. Could this be something simple (mechanic had no time to delve further as we were at a race track and he had to go get ready, or could it be a deeper issue. Before the overheated hub happened last Sunday, I had absolutely no issues with trailer brakes. Any suggestions are very welcome, as I am not a mechanic but can do a lot of stuff on a vehicle if I had to. Thanks in advance