Mercedes-Benz GL-Class: DEF
Important safety notes
For BlueTEC vehicles only.
DEF is a non-flammable, non-toxic, colorless, odorless and water-soluble fluid.
Only use DEF that complies with
ISO 22241. Do not add any special
additives to DEF and do not thin DEF with
water. This could destroy the BlueTEC
exhaust gas aftertreatment.
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.
High outside temperatures
If DEF heats up over 122 °F (50 °C ) for longer periods, e.g. as a result of direct sunlight on the DEF reservoir, DEF can decompose.
Ammonia vapors develop as a result.
WARNING
When opening the filler cap of the DEF tank
ammonia gas vapors may escape. Refill DEF in a well ventilated area only.
Ammonia gas
vapors have a pungent odor and are
particularly irritating for your skin, mucous
membranes, and eyes. Inhaling ammonia gas
vapors will cause burning eyes, nose, and
throat, as well as coughing and watering eyes.
Low outside temperatures
DEF freezes at a temperature of approximately 12 °F (–11 °C ). The vehicle is equipped with a DEF preheating system when it leaves the factory. Winter operation is therefore also guaranteed at temperatures below 12 °F(–11 °C ).
Additives
Only use DEF in accordance with ISO
22241. Do not use additives with DEF and
do not dilute DEF with water. This may
destroy the BlueTEC exhaust gas
aftertreatment system.
Damage resulting from the use of additives or water is not covered by the Mercedes- Benz Limited Warranty.
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
service products, cleaning agents or dust,
lead to increased emission values, system
malfunctions, catalytic converter damage
or damage to the BlueTEC system.
Additives in gasoline
One of the major problems with poor quality
fuels is the creation of carbon deposits during
the combustion process. Mercedes-Benz
recommends that you use fuel brands
containing additives that prev ...
Engine oil
...
See also:
Uniform tire quality grading
Quality grades can be found where applicable on the tire sidewall between the
tread shoulder and maximum section width. For example:
Treadwear 200 Traction AA Temperature A.
In addition to the mar ...
Speedometer with segments
The segments in the speedometer indicate
which speed range is available.
DISTRONIC activated:
One or two segments in the set speed range
light up.
DISTRONIC detects a vehicle in front:
T ...
Automatic Door Locks
The vehicle may have an automatic lock/unlock feature. This feature can be programmed
using the Driver Information Center (DIC). See Vehicle Personalization
for more information on DIC p ...