00 00 ... Battery: Checking display. If necessary, recharge battery.
WARNING: This page is about a different car, the 2007 BMW 550i and 2006 BMW 550i. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
Observe safety instructions for handling vehicle battery.
Vehicles with low-maintenance battery:
Check acid level, top up with distilled water if necessary
If level drops below Max. marking, top up distilled water to Max. marking.
Vehicles with maintenance-free battery:
Check charge start by way of magic eye