Mercedes-Benz electrical power steering system may fail.
Under such conditions, owners may get a warning on the dashboard that says:
Also, the red power steering light will come on.
If you get this warning, the steering wheel will be difficult to turn because the electric steering motor may be disabled.
The problem could be something as simple as a blown fuse to an issue with the power steering motor if your Mercedes-Benz has electric power steering.
If this message comes up while driving:
If the message comes up when you start the car:
Even though newer Mercedes-Benz cars have electric power steering, the steering has a mechanical link to the steering rack.
It is safe to drive only if you feel you have enough strength to turn the steering wheel manually.
Without the help of the steering motor, the steering wheel will be extremely hard to turn.
The system can malfunction if the battery is partially discharged, or the voltage regulator is not working correctly.
Charge the battery using a smart trickle charger.
There is a 125 A pre-fuse that feeds the power steering motor. This fuse can blow disabling the electric power steering assist.
If the fuse blows, it is an indication of a problem or lousy steering motor. The fuse is located in the prefuse box in the engine bay.
The power steering motor can fail which will make the steering very heavy to turn and also trigger the Steering Malfunction See Operator's Manual error message on the dashboard.
The steering motor is mounted on the steering rack and is easy to replace. If you need to replace the steering motor follow this guide.
The software for the electric steering may be the culprit and may need to be updated. You will have to take the car to the dealer to get the module updated.
Call your local dealer to check if there is an update available for your steering system.
Approximately 28,000 model-year 2015 Mercedes-Benz C300 and C400 4Matic sedans manufactured between Jan. 27 and Dec. 1, 2014 were recalled due to an error in the electric power steering control unit software.
Due to this problem a loss of electric power steering assist could occur, necessitating extra steering effort, particularly at lower speeds, and increasing the risk of a crash.