The same thing has happened to me twice now. The first time I did not have a trailer and the rear brakes locked up it felt like a tire blew but it did not. I thought maybe it was some type of forward crash alert or that maybe I hit a steel platform causing it to antilock. This time it just happened to me while I had my trailer and it happened all the sudden I was not accelerating and I was not near any other vehicles at all. I called my service advisor and will explain it to him and see what happens .