General information

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.

Check the battery in the SmartKey and replace it if necessary.
Unlock the driver's door using the mechanical key.
Lock the vehicle.
Have the starter battery and battery contacts checked at an authorized Mercedes-Benz Center.

If the SmartKey is faulty, contact Roadside Assistance or an authorized Mercedes-Benz Center.

    See also:

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