See also:

Displaying a service message
► Switch on the ignition. ► Press to select the standard display menu on the steering wheel. ► Select to select the service interval display. The service due date appears ...

Problems with the steering wheel heating
The steering wheel heating has switched off prematurely or cannot be switched on. The vehicle's electrical system voltage is too low because too many electrical consumers are switched on. - S ...

Cleaning the steering wheel and gear or selector lever
  Thoroughly wipe with a damp cloth or use leather care agents that have been recommended and approved by Mercedes- Benz. ...