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:

    Important safety notes
    WARNING For safety reasons, switch off the windshield wipers and remove the key from the ignition lock before changing the wiper blades (vehicles with KEYLESS-GO: make sure that the on-boar ...

    Roadside Assistance button
    – Press and hold Roadside Assistance button 1 for more than two seconds. This initiates a call to the Mercedes-Benz Customer Assistance Center. The indicator lamp in Roadside Assistance but ...

    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 ve ...