Flamingtaco

Seems putting voltage on the brake line (from the trailer battery, when you pull the break-away) is triggering the ITBC to function properly for a short time. I'd try swapping the controller next. Sounds like bad drivers in the controller.

Lenn

I thought about that but this problem presents itself on not only the 2013 F450 but also the 2011 F150.

Flamingtaco

Could be two controller with iffy drivers... rare, but possible. I'm otherwise out of ideas. One truck works fine, two others don't, it would appear the issue is with the two trucks, but... who knows. Ohm out the trailer pins to check for shorts, if none are present, the issue should lie in the trucks.