To improve fuel savings the alternator is designed to charge on deceleration and take advantage of the vehicle's kinetic energy.
I too have had that message displayed but after a five minute drive in sport mode with plenty of intended engine revving (gearing down) the battery was good to go. Actually one of my HID headlights failed during this incident but magically fixed itself upon restart (designed by Microsoft... haha, fixed by a simple re-boot).
I have thought about hooking up my multimeter to the battery to confirm the car only charges on deceleration... but hell, a $50-70K car should be smart enough to charge the battery if discharged regardless of accelerating or decelerating...
Last edited by lbjgh; 12-28-2012 at 02:10 PM.