NGBSDG BSD interface to alternator: Notes
WARNING: This page is about a different car, the 2013 BMW X5, 2012 BMW X5, and 2011 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.
The alternator with its BSD interface supports active communications with the engine-management control unit. The alternator is not directly connected to the charge-indicator lamp, but rather to the engine-management control unit. The alternator can detect various defects and malfunctions.