See also:

Switching the rear-compartment climate control on/off using the front control panel
Turn the SmartKey to position 2 in the ignition lock. Activate the rear compartment function via COMAND. The rear-compartment climate control can be controlled via the front control panel ...

Additives
Do not use any additives in the engine oil. This could damage the engine. ...

Important safety notes
Important safety notes Do not leave the SmartKey in the cargo compartment. You could otherwise lock yourself out WARNING   When leaving the vehicle, always remove the SmartKey from the ...