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:

    SmartKey
    Display messages Possible causes/consequences and •► Solutions Key Does Not Belong to Vehicle You have put the wrong SmartKey in the ignition lock. •► Use the correct ...

    Adjusting the climate mode settings (AIR FLOW)
    This function is only available with automatic climate control. The climate control settings are especially effective at high temperatures. You can select the following climate control setting ...

    Fuse box in the rear
    The fuse box is behind the armrest in the rear. To open: fold down the armrest. Pull handle 1 on the trim behind the rear seat armrest up in the direction of the arrow. Fold down trim 2. ...