The Servotronic is a speed-dependant power steering control system.
The Servotronic is integrated in the general module.
The current for the electrohydraulic converter is controlled in the general module dependent on the driving speed. The higher the speed, the lower the converter current.
On E38 vehicles, the speedometer A-signal line is connected from the IKE to the general module for the purpose of evaluating the vehicle speed. In order to detect errors, in addition to the speedometer A-signal, the speed value is also transferred from the IKE via the K-bus to the general module.
On E39 and E53 vehicles, the wheel speed signal from the ABS/ASC control unit is used instead of the speedometer A signal.