Purity

Assuring the purity of DEF is particularly important with respect to avoiding malfunctions in the exhaust gas aftertreatment system.

If DEF is pumped out of the DEF tank, e.g. during repair work, it must not be returned to the tank. The purity of the fluid can no longer be guaranteed.

service products, cleaning agents or dust) Impurities in DEF (e.g. due to other service products, cleaning agents or dust) lead to:
• increased emission values
• damage to the catalytic converter
• engine damage
• malfunctions in the BlueTEC exhaust gas aftertreatment system

    See also:

    Coupling up a trailer
    WARNING Vehicles with air suspension program: While you are coupling or decoupling a trailer, make sure nobody locks or unlocks the vehicle and/or opens or closes doors or the tailgate. The v ...

    Adjusting the seats in the second andthird rows
    Important safety notes WARNING   Never travel in a moving vehicle with the seat backrest in an excessively reclined position as this can be dangerous. You could slide under the seat bel ...

    Adding DEF
    WARNING Make sure - DEF does not come into contact with skin, eyes, or clothing - to keep DEF out of the reach of children If you and/or others have come into contact with DEF: - If DEF has gott ...