See also:

Switching on automatically
With the engine running or the ignition switched on, shift the selector lever into position R. ...

Automatic-Transmission
Starting the engine 1. Depress the brake pedal. 2. Press the Start/Stop button. The ignition is activated automatically for a certain time and is stopped as soon as the engine starts. ...

Note
Children in the vehicle Do not leave children unattended in the vehicle; otherwise, they could endanger themselves and other persons, e.g., by opening the doors. ...