See also:

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, ...

General notes
WARNING All categories of messages contain important information which should be taken note of and, where a malfunction is indicated, addressed as soon as possible at an authorized Mercedes- ...

Using KEYLESS-GO to start the engine
WARNING As long as the SmartKey is in your vehicle, the vehicle can be started. Therefore, never leave children unattended in the vehicle, as they could otherwise accidentally start the engine ...