The other day I used my small utility trailer for the first time with my 2020 2500. After connecting and starting the truck, it listed my fifth wheel, Guest trailer or set up a new one. Didn't have time to set it up, so I just chose Guest and moved on. When I returned, I cut off the truck, disconnected and put the trailer away. I didn't use the truck for two days. When I went out, the truck was completely dead. It had enough juice to unlock the doors once, then would do nothing else.
I had to set my charger to 100A jumpstart for 10 minutes before I was able to get it started. Then, without a trailer connected, it gave me the error message to maintenance the trailer brakes. That trailer didn't have brakes. I'm assuming it had something to do with the trailering app/computer, but it has cranked every time since.