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:

    Starting procedure with the SmartKey
    To start the engine using the SmartKey instead of KEYLESS-GO, pull the Start/ Stop button out of the ignition lock. X Turn the SmartKey to position 3 in the ignition lock () and release it as ...

    Message memory
    The on-board computer saves certain display messages. You can call up the display messages in the message memory. – Press the or button on the steering wheel to select the Serv. menu. If th ...

    Trailer towing
    When towing a trailer and driving downhill, shift to the lower gear if the automatic transmission constantly shifts between two gears. Engaging a lower gear and reducing the speed reduces the ...