Brake controller issues

Just bought a new travel trailer (8500 lbs)and was making a two day trip. First day everything went fine. On the second day after about 1/2 hour if I touched the brakes the trailer would momentarily jerk real hard. This happened several times and I got a warning that trailer wiring was incorrect see owners manual. Couldn’t find anything in the owners manual. It finally got to the point when I applied the brakes it started this hard jerking about once a second. I was finally able to pull the truck off the side of the road while the brakes kept jerking. Foot on gas not on brakes. When I finally got stopped they quit working all together. At least I could move the trailer. After stopping for gas the jerking resumed. I made it home by getting an adapter to plug in the 4 flat plug and bypassing the brakes. Anyone have a clue? The truck is a 17 with the IBC. If I purchase an aftermarket unit does it still use the factory ECU?

 

There is a service bulletin for a software reflash on the Ibc in the tundra. Yes, people have put in aftermarket contollers.

 

Do you know if the aftermarket controller such as the P3 uses any of the trucks electronics or just the wiring from the dash to the trailer plug?

 

I have not heard of any aftermarket controller using the truck's electronics. The 2018 and newer Tundras use electronics between the controller and the trailer plug, that is why plug and play controllers don't work on 2018 and later.