I'd like to add what I found on this issue on my Bighorn with the 8.4" uconnect
I parked my truck on Tuesday night, used my company car for work on Wednesday and Thursday and Thursday evening went start my truck and dead. No lights, no remote unlock, nothing! I checked my security cameras to see if I left lights on or if anyone messed with the truck. Since I back my truck in the drive you can see through the back window to the dash when it's dark. After I parked the truck you can see the lights flash showing that I locked it, 10 seconds later, lights go off, about 30 seconds later the dash lights go off. About 20 minutes later, I can't remember if I locked the doors or not so I hit the lock button from inside the house. In my security camera you can see the lights flash and instrument cluster lights up but never goes off. When I leave for work Wednesday morning you can see the instrument cluster still on. When I get home that night after dark no more instrument cluster lighting up.
After getting my battery charged back up I decided to try a few things. If you lock the doors with the remote when they are already locked, the instrument lights up and stays on. If you unlock the door, open the door, close the door then lock them with the remote, sometimes the instrument shuts off after 30 seconds and sometimes it stays on. If you unlock the door, start the truck, then turn it off get out and lock the doors, the instrument cluster always turns off after 30 seconds.
Seems to be a weird glitch in the software but I'm keeping an eye on it and will be letting the dealer know when I take it in for the power steering ground recall.