See also:

Important safety notes
WARNING When leaving the vehicle, always remove the SmartKey from the ignition lock. Always take the SmartKey with you and lock the vehicle. Do not leave children unattended in the vehicle, ...

System self-test
The 42 indicator lamp illuminates when you: • turn the SmartKey to position 1 or 2 in the ignition lock • on vehicles with KEYLESS-GO, press the Start/Stop button once or twice The indicator ...

Safety
As it should be, the M-Class is full of standard safety features like an electronic stability system, antilock brakes, traction control, side curtain airbags, and side-impact airbags for the front ...