See also:

Important safety notes
For reasons of safety, Mercedes-Benz recommends that you drive with the lights switched on even during the daytime. In some countries, operation of the headlamps varies due to legal requirements a ...

High outside temperatures
If DEF heats up to over 122 °F (50 °C ) for extended periods, e.g. as a result of direct sunlight on the DEF reservoir, DEF can decompose. Ammonia vapors develop as a result. WARNING When o ...

Roadside Assistance button
Open the stowage compartment under the armrest. Press and hold Roadside Assistance button 1 for more than two seconds. This initiates a call to the Mercedes-Benz Customer Assistance Center ...