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.

Impurities in DEF (e.g. due to other 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:

    Displaying service messages
    Switch on the ignition. Press or on the steering wheel to select the Serv. menu. Press or to select the ASSYST PLUS submenu and press to confirm. The service due date appears ...

    Redialing
    The on-board computer saves the last names or numbers dialed in the redial memory. – Press the or button on the steering wheel to select the Tel menu. – Press the button to switch to the r ...

    Cleaning the display
    Before cleaning the display, make sure that it is switched off and has cooled down. Clean the display surface using a commercially-available microfiber cloth and TFT/LCD display cleaner. Dr ...