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Structure and inner electrical connection

The alternator has a separate terminal for the positive battery lead. The control variables (e.g. nominal voltage of alternator) are transferred to the controller via the serial data interface (BSD or LIN).

The regulator is attached to the back of the alternator.

Fig 1: Identifying Electronic Component With Controller
G09895083Courtesy of BMW OF NORTH AMERICA, INC.
Index Explanation
1 Electronic component with controller
PIN ASSIGNMENTS DESCRIPTION

Pin Explanation
BSD/LIN serial data interface (BSD or LIN)
U Positive battery cable