Boy! This issue just doesn't go away.
To my surprise, about two weeks ago, went to the garage to get our 2.8 X3. It was dead as a doornail. No lights, no response from the key, nothing. Access was only from the conventional lock on the drivers door. I put a multimeter on the underhood terminals and it read 3volts. The car had been used daily prior, albeit local errands only. No indication of any issues. No battery warnings at all. A call to the dealer brought roadside assist. The tech was able to start the X3 immediately with a jump. I drove it for 25-30 minutes and its been fine ever since. Now, after a check up two days later at the dealer, it was pronounced OK and the cause was a phone charger left in the console outlet!! The SA claims that although the outlets turn off they can be "woking up" or awakened if something is plugged in. Now I'm not sure what to believe. Anyone?