See also:

Cleaning the wiper blades
WARNING Before cleaning the windshield or wiper blades, switch off the windshield wipers and remove the SmartKey from the ignition lock. On vehicles with KEYLESS-GO, press the Start/Stop but ...

Cockpit
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Roadside Assistance button
X Press and hold Roadside Assistance button 1 for more than two seconds. This initiates a call to the Mercedes-Benz Customer Assistance Center. The indicator lamp in Roadside Assistance button 1 ...