General notes

If you cannot lock or unlock the vehicle with the SmartKey, either the battery in the SmartKey is discharged, the SmartKey is faulty or the starter battery is discharged.

SmartKey and replace it if necessary. Check the battery in the SmartKey and replace it if necessary.
mechanical key. Unlock the driver's door using the mechanical key.
mechanical key. Lock the vehicle using the mechanical key.
battery contacts checked at a qualified specialist workshop. Have the starter battery and the battery contacts checked at a qualified specialist workshop.

If the SmartKey is faulty, contact Roadside Assistance or a qualified specialist workshop.

    See also:

    Engaging the differential locks
    Pull away slowly when the differential locks are activated. Function or performance tests may only be performed on a 2-axle dynamometer. If you wish to operate the vehicle on such a dynamomet ...

    Call priority
    When service calls are active, e.g. Roadside Assistance or MB Info calls, an emergency call can still be initiated. In this case, an emergency call will take priority and override all other ac ...

    Problems with the seat heating
    The seat heating 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. X Switch off ...