Mercedes-Benz Electric Steering Noise
This bulletin applies to Mercedes-Benz vehicles equipped with electric steering, such as 2017 CLS400 vehicles. A rattling/humming noise may be heard from the electric steering system.
The ball screw drive of electric steering may be damaged by external forces such as hitting the curb with the front wheels, driving over obstacles (bumps, potholes, etc.) at an inappropriate speed, and/or corrosion ingress through a damaged rack boot, any of which can require replacement of the steering gear.