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:

    Important safety notes
    WARNING Always remember that you must concentrate primarily on driving the vehicle. The driver's concentration must always be directed primarily at road traffic. For your own safety and tha ...

    Cleaning the wiper blades
    WARNING Before cleaning the windshield or wiper blades, switch off the windshield wipers and remove the SmartKey from the ignition lock. On vehicles with KEYLESS-GO, press the Start/Stop b ...

    Muscular Moves
    Shortly after last year's GL450 arrived, Mercedes introduced a diesel GL320 CDI; click here to compare the 2008 GL-Class with the 2007 model. Thanks to the higher efficiency of its diesel engine, ...