If I'm sitting in the cargo area with my laptop plugged into the rear power outlets, does the key have to be in position 1, or 2. Or can I run off from the battery until it completely discharges. I seem to remember, either my salesman or the video tape saying that the X5 will let the battery discharge until a certain point then shut down the electrical system. I can't find this in the manual. Wonder if this addresses the issue for those folks reporting dead batteries. Maybe there is a bug there. I can't find any references to 'passive battery drain' in internet searches related to cars, just submarines.