Windshield leak (common problem). Water drips down and shorts the GEM module. Drains battery.
Good luck reaching the GEM module. Mine finally dried out by itself and went back to normal.
Word.
My son's F250 Powerstroke did this. It would start cranking in the middle of the night with no one around. Radio, heater blower and cab lights would come on by themselves as well. Finally put on an RV ground cable cut-off relay to stop the demons.
Got to wait 'til he comes home to do a proper fix.
+1 for the windshield leaking on the gem. Seen it a few times.