See also:

Charging the battery
WARNING Never charge a battery still installed in the vehicle unless a battery charger unit approved by Mercedes-Benz is being used. Gases may escape during charging and cause explosions ...

Checking the coolant level
Only check the coolant level when the vehicle is on a level surface and the engine has cooled down. ► Turn the SmartKey to position 2 in the ignition lock. On vehicles with KEYLESS-GO, ...

Problems with the seat ventilation
The seat ventilation 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. - Switch ...