See also:

Unlocking the driver's door (mechanical key)
If the vehicle can no longer be unlocked with the SmartKey, use the mechanical key. If you use the mechanical key to unlock and open the driver's door, the anti-theft alarm system will be trigg ...

Transfer case
This section is only valid for vehicles with 4- wheel drive (4MATIC). Power is always transmitted to both axles. Performance tests may only be carried out on a 2-axle dynamometer. The brake sy ...

System self-test
If an adult occupant is properly sitting on the passenger seat and the OCS classifies the occupant as an adult, the indicator lamp illuminates and goes out again after approximately 6 seconds ...