See also:

Parking the vehicle for a long period
If you leave the vehicle parked for longer than four weeks, the battery may be damaged by exhaustive discharge. ► Connect a trickle charger. You can obtain information about trickle ch ...

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. Check the battery in ...

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 ...