This occurs intermittently and typically right after a start up and I'm starting to back up. The message blinks rapidly on the dash about Trailer Braking Gain. The dashboard red light that reflects on the windshield blinks and the seat (lane deviation) thumps like crazy. Then as suddenly as it began, it quits. Only to return in about 60 seconds. I usually shut off the truck, go to the trailer wire harness connector (the round 8 contact type) and just blow out any debris and wipe the contacts to ensure no ground faults and whether that resolves it or shutting off the truck did, I do not know. This has occurred 3 times in two years. Intermittent electronic anomalies are the hardest to troubleshoot so I won't take it in unless it's constantly doing it.