Cycle through your dash display until you get to the battery voltage screen. Look at the note to the RH side of the gauge. It says something like "hold down the OK button" for a certain amount of time to enter "storage mode" and starts a count down. When it gets to zero, everything and I mean everything shuts off. Key fob doesn't work, power steps off line, everything. To exit this mode, start the truck. it takes a while for everything to come back online. The main infotainment screen tool almost 15 minutes of driving to come back on when I tested it.