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 charg ...

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. - ...

Notes for 4MATIC vehicles
Vehicles with 4MATIC must not be towed with either the front or the rear axle raised, as doing so will damage the transmission. If the vehicle has transmission damage or damage to the front ...