See also:

Floormat on the driver's side
WARNING Whenever you are using a floormat, make sure there is enough clearance and that the floormat is securely fastened. The floormat should always be securely fastened using the fastening ...

Additives
Only use DEF in accordance with ISO 22241. Do not use additives with DEF and do not dilute DEF with water. This may destroy the BlueTEC exhaust gas aftertreatment system. ...

Immobilizer
The immobilizer prevents your vehicle from being started without the correct SmartKey. When leaving the vehicle, always take the SmartKey with you and lock the vehicle. The engine can be started ...