We bought a used 2015 Odyssey about two weeks ago and are still learning how to operate all the features. Earlier this week my husband decided to stay in the car in the passenger seat with the accessory mode on and set the radio stations while I went into a store. While he was seeking stations and listening to the radio, all the power in the car suddenly died. When I returned to the car, not even the door locks worked. I was unable to unlock the driver's door with my automatic key and had to use the actual key to get back into the car. Nothing we tried would start the car. The dealer sent out a tow truck. The tow truck driver worked with the battery and managed to start the car. It was too late by then to go directly to the dealer, so we went home and called the next day. We have an appointment to take the car in for service tomorrow. In the meantime, we received the 2015 Odyssey Owner's Manual I ordered in the mail and learned by reading the manual that this model has an Automatic Power Off feature that will automatically cut power to the car if it's left parked with the accessory mode on for 30 minutes to an hour. The owner's manual said to press the Engine Start/Stop button twice to switch to standard Vehicle Off mode. Today we decided to try to duplicate the problem, see if we could get out of the Automatic Power Off mode, and possibly save a trip to the dealer for service. We ran the car in Accessory Mode for almost an hour and experimented with how various features work before I turned on the CD player. Soon after I turned on the CD player, all the power died. I could press the Start/Stop button twice to get Power On to come back on, but could not return to full accessory mode. As soon as I press the brake to try to start the car, all the power goes out again. We tired jump starting the car. Battery shows okay, but car still won't start. Ideas on what to do now?