See also:

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. ...

Door control panel
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Locking the vehicle
If the vehicle can no longer be locked with the SmartKey, you can lock it by taking the following steps. ► Close the front-passenger door, the rear door on the front-passenger side and the ...