Problems with the SmartKey

Problem Possible causes/consequences and Solutions
You cannot lock or unlock the vehicle using the SmartKey. The SmartKey battery is discharged or nearly discharged.
- Try again to lock/unlock the vehicle using the remote control function of the SmartKey. Point the tip of the SmartKey at the driver's door handle from close range and press the button./button. button.
If this does not work:
- Check the SmartKey battery and replace it if necessary.
- Lock or unlock the vehicle using the mechanical key.
The SmartKey is faulty.
- Lock or unlock the vehicle using the mechanical key.
- Have the SmartKey checked at a qualified specialist workshop.
You can no longer lock or unlock the vehicle using KEYLESS-GO. There is interference from a powerful source of radio waves.
- Lock/unlock the vehicle using the remote control function of the SmartKey. Point the tip of the SmartKey at the driver's door handle from close range and press the button./button. button.
There is a malfunction with KEYLESS-GO.
- Lock/unlock the vehicle using the remote control function of the SmartKey. Point the tip of the SmartKey at the driver's door handle from close range and press the button./button. button.
- Have KEYLESS-GO checked at a qualified specialist workshop.
If this does not work:
- Check the SmartKey battery and replace it if necessary.
- Lock or unlock the vehicle using the mechanical key.
You have lost a SmartKey. - Have the SmartKey deactivated at a qualified specialist workshop.
- Report the loss immediately to the vehicle insurers.
- If necessary, have the locks changed as well.
You have lost the mechanical key. - Report the loss immediately to the vehicle insurers.
- If necessary, have the locks changed as well.
The engine cannot be started using the SmartKey. The on-board voltage is too low.
- Switch off non-essential consumers, e.g. seat heating or interior lighting, and try to start the engine again.
If this does not work:
- Check the starter battery and charge it if necessary.
or
- Jump-start the vehicle.
or
- Consult a qualified specialist workshop.
The engine cannot be started using KEYLESS-GO.
The SmartKey is in the vehicle.
A door is open. Therefore, the SmartKey cannot be detected as easily.
- Close the door and try to start the vehicle again.
There is interference from a powerful source of radio waves.
- Start your vehicle with the SmartKey in the ignition lock.
    See also:

    De-authorizing (de-registering) a Bluetooth® device
    Mercedes-Benz USA, LLC recommends deauthorization in both COMAND and the Bluetooth® device, e.g. the mobile phone. Subsequent authorization may otherwise fail. In the Bluetooth® device list, se ...

    Standard display
    Press and hold the button on the steering wheel until the Trip menu with odometer 1 and trip odometer 2 is shown. ...

    Switching COMAND on/off
    Press the function button on the center console. If you switch off COMAND, playback of the current audio or video source will also be switched off. You cannot switch off COMAND while mak ...