Adding DEF

Make sure 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 gotten into contact with eyes, flush with plenty of water immediately and seek medical help.
- Clean affected skin immediately with plenty of water.
- If DEF was swallowed, rinse mouth immediately with plenty of water and drink plenty of water. Consult a physician.

If you open the DEF tank cap, small amounts WARNING
If you open the DEF tank cap, small amounts of ammonia vapor may be released. This depends in particular upon the age of the DEF.
Ammonia vapors have a pungent odor and are particularly irritating to:
- skin
- mucous membranes
- eyes
You may experience a burning sensation in your eyes, nose and throat, as well as coughing and watering of the eyes.
Do not inhale any ammonia vapors that may be released. Fill the DEF tank only in wellventilated areas.

Only use DEF in accordance with Only use DEF in accordance with ISO 22241. Do not mix any additives with DEF, and do not dilute DEF with water. This may destroy the BlueTEC exhaust gas aftertreatment system.

The vehicle must be parked on level The vehicle must be parked on level ground to fill the DEF tank. The DEF tank can only be filled as intended with the vehicle parked on a level surface. This avoids false level readings. Filling the tank is not permitted if the vehicle is not parked on a level surface. There is a danger of overfilling, which could result in damage to components of the BlueTEC exhaust gas aftertreatment.

If the outside temperature is lower than - 11 °C, damage may occur when adding DEF.

If DEF is frozen and there is an active warning indicator, adding may not be possible. Park the vehicle in a warmer place, e.g. in a garage, until DEF has become fluid again. Filling is then possible again. Alternatively, have the DEF tank refilled at a qualified specialist workshop.

Rinse surfaces that have come into Rinse surfaces that have come into contact with DEF immediately with water or remove DEF using a damp cloth and cold water. If the DEF has already crystallized, use a sponge and cold water to clean it. DEF residues crystallize after time and contaminate the affected surfaces.

DEF is not a fuel additive and must not be DEF is not a fuel additive and must not be added to the fuel tank. If DEF is added to the fuel tank, this can lead to engine damage.

Further information on DEF.

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