126Driving and operating
take up to 25 minutes. Typically it
needs between 7 and 12 minutes.
Autostop is not available and fuel
consumption may be higher during
this period. The emission of smells
and smoke during this process is
normal.
Under certain driving conditions, e.g.
short distances, the system cannot
clean itself automatically.
If cleaning of the filter is required and if previous driving conditions did not
enable automatic cleaning, it will be
indicated by control indicator %.
% illuminates when diesel particle
filter is full. Start cleaning process as
soon as possible.
% flashes when diesel particle filter
has reached the maximum filling level. Start cleaning process
immediately to avoid damage to the
engine.
Cleaning process To activate cleaning process,
continue driving, keep engine speed
above 2000 revolutions per minute.
Shift down if necessary. Diesel
particle filter cleaning is then started.
If control indicator g also
illuminates, cleaning is not possible:
seek the assistance of a workshop.Caution
If the cleaning process is
interrupted, there is a risk of
provoking severe engine damage.
Cleaning takes place quickest at high engine speeds and loads.
The control indicator % extinguishes
as soon as the self-cleaning
operation is complete.
Catalytic converter
The catalytic converter reduces the
amount of harmful substances in the
exhaust gases.Caution
Fuel grades other than those listed on pages 3 148, 3 205 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
Driving and operating131Drive systems
All-wheel drive The All-Wheel Drive (AWD) system
enhances driving characteristics and stability, and helps to achieve the best possible driveability regardless of
ground surface. The system is always
active and cannot be deactivated.
The torque is distributed steplessly
between the wheels of the front and rear axle, depending on the driving
conditions. Additionally the torque
between the rear wheels is distributed
depending on the surface.
For optimum system performance,
the vehicle's tyres should not have
varying degrees of wear.
When using a temporary spare
wheel, the AWD system is
automatically disabled.
The AWD system will also be
temporarily disabled to protect the
system from overheating if there is
excessive wheel spin. When the
system cools down, AWD will be
restored.The deactivation of the AWD system
will be indicated by a message on the
Driver Information Centre.
If a service message or warning
code S73 is displayed on the Driver Information Centre, there is a
malfunction in the AWD system. Seek the assistance of a workshop.
Vehicle messages 3 95, Towing the
vehicle 3 191.Brakes
The brake system comprises two
independent brake circuits.
If a brake circuit fails, the vehicle can
still be braked using the other brake
circuit. However, braking effect is
achieved only when the brake pedal
is depressed firmly. Considerably
more force is needed for this. The
braking distance is extended. Seek the assistance of a workshop before
continuing your journey.
When the engine is not running, the
support of the brake servo unit
disappears once the brake pedal has been depressed once or twice.
Braking effect is not reduced, but
braking requires significantly greater
force. It is especially important to bear this in mind when being towed.
Control indicator R 3 85.
Antilock brake system Antilock brake system (ABS)
prevents the wheels from locking.
