Ever since I hooked up my trailer, to test and make sure everything was working (haven't towed yet), my trailer brake screen is showing the % of brake being used (as I apply the brakes), even when there is no trailer hooked up. I don't think it was showing any % before I plugged in my trailer. Can anyone confirm? It seems like on my 2013 it would only show how much trailer brake was being applied when the trailer was hooked up. Thanks.