164Driving and operatingCaution
If the cleaning process is
interrupted, there is a risk of
provoking severe engine damage.
Cleaning process not possible
If cleaning is not possible for anyreasons, Z illuminates and a warning
message appears in the Driver
Information Centre. Engine power
may be reduced. Seek the assistance
of a workshop immediately.
Catalytic converter
The catalytic converter reduces the
amount of harmful substances in the
exhaust gases.
Caution
Fuel grades other than those listed on pages 3 213, 3 283 could
damage the catalytic converter or
electronic components.
Unburnt petrol will overheat and
damage the catalytic converter.
Therefore avoid excessive use of the starter, running the fuel tank
dry and starting the engine by
pushing or towing.
In the event of misfiring, uneven
engine running, a reduction in engine performance or other unusual
problems, have the cause of the fault
rectified by a workshop as soon as
possible. In an emergency, driving
can be continued for a short period,
keeping vehicle speed and engine
speed low.
AdBlue
General information
The selective catalytic reduction
(BlueInjection) is a method to
substantially reduce the nitrogen
oxides in the exhaust emission. This
is achieved by injecting a Diesel
Exhaust Fluid into the exhaust
system. The ammonia released by
the fluid reacts with nitrous gases
(NO x) from the exhaust and turns it
into nitrogen and water.
The designation of this fluid is AdBlue
® . It is a non-toxic, non-flammable,
colourless and odourless fluid which
consists of 32% urea and 68% water.9Warning
Avoid contact of your eyes or skin
with AdBlue.
In case of eye or skin contact,
rinse off with water.
170Driving and operatingTemporary manual mode in drive
mode D
Manual paddle shifting is also
possible in automatic mode D. Upon
completion of manual shifting
operation, transmission changes to
automatic mode D after a defined
time.
To interrupt manual mode, do one of
the following:
● Press < paddle for 1 second.
● Move selector lever towards the left to manual mode and back to
position D.
If the vehicle is at a standstill and
engine is idling, the transmission will remain in temporary manual mode. It
changes to automatic mode when
accelerator pedal is operated for a
defined time, and no paddle shifting
at the steering wheel is performed.
General If a higher gear is selected when
vehicle speed is too low, or a lower
gear when vehicle speed is too high,the shift is not executed. This can
cause a message in the Driver
Information Centre.
In manual mode, no automatic
shifting to a higher gear takes place
at high engine revolutions.
Gear shift indication
The symbol R with a number below it
is indicated when gearshifting is
recommended for fuel saving
reasons.
Shift indication appears only in
manual mode.
Electronic driving programmes
● Following a cold start, the operating temperature
programme increases engine
speed to quickly bring the
catalytic converter to the required
temperature.
● The automatic neutral shift function automatically shifts to
idling when the vehicle is stopped
with a forward gear engaged and the brake pedal is pressed.● When SPORT mode is engaged,
the vehicle shifts at higher engine speeds (unless cruise control is
on). SPORT mode 3 178.
● Special programmes automatically adapt the shifting
points when driving up inclines or
down hills.
● When starting off in snowy or icy conditions or on other slippery
surfaces, the electronic
transmission control selects a
higher gear automatically.
Kickdown If the accelerator pedal is pressed
down completely in automatic mode,
the transmission shifts to a lower gear
depending on engine speed.
Overheat protection
In the event of transmission-
overheating due to high outside
temperatures or sporty driving style,
the torque and the maximum speed of the engine can be temporarily
reduced.
