This is NOT BS, my truck did this several times...got the the "no light on, no problem with this truck, can't replicate" speech by some idiot service manager. Why on earth would someone make this up?! I am just coming across this thread tonight for the first time, I explain that I had the same issue here:
http://www.gm-trucks.com/forums/topic/162450-does-your-2014-do-this/?p=1478378
I made that post on July 16th, never in my experience have I had a vehicle do this. But, to this date I haven't been driving it because its been at my dealer for water leaks, and other various issues for about a month now.