Ending Android Auto
To end the connection of Android Auto (wireless and wired):
de-authorise the mobile phone in the 
device list under the application More. or
In the device list, select the symbol for the Bluetooth® HFP profile (Hands Free Profile) in the line of the mobile phone.
device list, select the symbol for the Bluetooth® HFP profile (Hands Free Profile) in the line of the mobile phone. The mobile phone remains connected with the system via the Bluetooth® HFP profile.
With Android Auto (wired): disconnecting the connecting cable does not automatically lead to Android Auto (wired) ending. If required, the system can establish the connection via Android Auto (wireless), which can in turn be disconnected using the device list.
Mercedes-Benz recommends disconnecting only when the vehicle is stationary.