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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. ...

Step-by-step instructions
The following steps have been developed as required of all manufacturers under Title 49, Code of U.S. Federal Regulations, Part 575 pursuant to the "National Traffic and Motor Vehicle Saf ...

Switching the windshield wipers on/ off
WARNING Wiper blades are components that are subject to wear and tear. Replace the wiper blades twice a year, preferably in the spring and fall. Otherwise the windshield will not be wiped ...