Battery care and maintenance
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2006 BMW M3, 2005 BMW M3, 2004 BMW M3, 2003 BMW M3, and 2002 BMW M3. However, it is still accessible from the selected car via links, so may be relevant.
In low-maintenance batteries, check the acid level at least once a year. If necessary, top up with distilled water up to the top marking.
The increasing number of electronic control units in the car reduces the self-discharging time of the battery (even in standby mode). To maintain the battery service life and to avoid exhaustive discharging, recharge laid-up vehicles every 6 weeks at the latest (refer to battery recharging schedule here, SI 6 10 398 387). The time for self-discharging depends on vehicle type and equipment specification.