You can also remove and rotate the plastic wheel 180 degrees to get new contact surface.

Servotronic is only connected to DSC by the wheel speed sensor signal (vehicle speed) coming from left rear sensor (same as instrument cluster). In this case the code is for Servotronic solenoid and likely too small resistance caused by tired solenoid. You can measure the solenoid resistance via the body module connector pins. If resistance is below 7,5 ohm body module will show this trouble code.

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E39 530dA -02 M-Sport Messing metallic
E53 X5 3.0dA -06 Sport Stratus grey