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Driving and operating135Driving hints
Control of the vehicle
Never coast with engine not
running (except during Autostop)
Many systems will not function in this
situation (e.g. brake servo unit, power steering). Driving in this manner is a
danger to yourself and others. All
systems function during an Autostop,
but there will be a controlled reduction
in power steering assist and vehicle
speed is reduced.
Stop-start system 3 137.
Idle boost
If charging of the battery is required
due to battery condition, the power
output of the generator has to be
increased. This will be achieved by an idle boost which may be audible. A
message is displayed in the Driver
Information Centre.Pedals
To ensure the pedal travel is
uninhibited, there must be no mats in the area of the pedals.
Use only floor mats, which fit properly
and are fixed by the retainers on the
driver's side.
Steering If power steering assist is lost
because the engine stops or due to a
system malfunction, the vehicle can
be steered but may require increased
effort.
Control indicator c 3 90.Caution
Vehicles equipped with hydraulic
power steering:
If the steering wheel is turned until it reaches the end of its travel, and
is held in that position for more
than 15 seconds, damage may
occur to the power steering
system and there may be loss of
power steering assist.
Ground clearance
Due to the reduced ground clearance,
the vehicle can be damaged
depending on the vehicle loading and
appearance of the ground. Take
special care and drive slowly on steep driveways, entry and exit of parking
garages, high kerbs and uneven
surfaces. If possible, drive diagonally
with one wheel after another when running over kerbs or uneven
surfaces.
Page 138 of 263

136Driving and operatingStarting and operating
New vehicle running-in
Do not brake unnecessarily hard for
the first few journeys.
During the first drive, smoke may
occur because of wax and oil
evaporating off the exhaust system.
Park the vehicle in the open for a
while after the first drive and avoid
inhaling the fumes.
During the running-in period fuel and engine oil consumption may be
higher and the cleaning process of
the diesel particle filter may take
place more often. Autostop may be
inhibited to allow for charging the
vehicle battery.
Diesel particle filter 3 141.Ignition switch positions0:ignition off1:steering wheel lock released,
ignition off2:ignition on, for diesel engine:
preheating3:starting
Retained power off
The following electronic systems can
work until the driver's door is opened
or for a maximum of 10 minutes after
the ignition is switched off:
● power windows
● power outlets
Starting the engine
Manual transmission: operate clutch.
Automatic transmission: operate
brake and move the selector lever to
P or N.
Do not operate the accelerator pedal. Diesel engine: turn the key to position2 for preheating until control
indicator ! extinguishes.
Turn the key briefly to position 3 and
release: an automatic procedure
operates the starter with a short delay
as long as the engine is running, see
'Automatic Starter Control'.
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Driving and operating137Before restarting or to switch off the
engine, turn the key back to position
0 .
During an Autostop, the engine can
be started by depressing the clutch
pedal.
Starting the vehicle at low
temperatures
Starting the engine without additional heaters is possible down to -25 °С for
diesel engines and -30 °C for petrol
engines. Required is an engine oil
with the correct viscosity, the correct
fuel, performed services and a
sufficiently charged vehicle battery.
With temperatures below -30 °C the
automatic transmission needs a
warming phase of approx. 5 minutes.
The selector lever must be in position
P .
Automatic Starter Control
This function controls the engine
starting procedure. The driver does
not have to hold the key in position 3.
Once applied, the system will go on starting automatically until the engineis running. Because of the checking
procedure, the engine starts running
after a short delay.
Possible reasons for a non-starting
engine:
● Clutch pedal not operated (manual transmission).
● Brake pedal not operated or selector lever not in P or N
(automatic transmission).
● Timeout occurred.
Turbo engine warm-up
Upon start-up, engine available
torque may be limited for a short time, especially when the engine
temperature is cold. The limitation is
to allow the lubrication system to fully
protect the engine.
Overrun cut-off
The fuel supply is automatically cut off
during overrun, i.e. when the vehicle
is driven with a gear engaged but accelerator pedal is released.
Depending on driving conditions, the
overrun cut-off may be deactivated.Stop-start system
The stop-start system helps to save
fuel and to reduce the exhaust
emissions. When conditions allow, it
switches off the engine as soon as the
vehicle is at a low speed or at a
standstill, e.g. at a traffic light or in a
traffic jam. It starts the engine
automatically as soon as the clutch is depressed. A vehicle battery sensor
ensures that an Autostop is only
performed if the vehicle battery is
sufficiently charged for a restart.
Activation The stop-start system is available as
soon as the engine is started, the
vehicle starts-off and the conditions
as stated below in this section are
fulfilled.
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138Driving and operatingDeactivation
Deactivate the stop-start system
manually by pressing eco. The
deactivation is indicated when the
LED in the button extinguishes.
Autostop If the vehicle is at a low speed or at a
standstill, activate an Autostop as
follows:
● Depress the clutch pedal.
● Move the selector lever to neutral.
● Release the clutch pedal.
The engine will be switched off while
the ignition stays on.
An Autostop is indicated by the
needle at the AUTOSTOP position in
the tachometer.
During an Autostop, the heating and
brake performance will be
maintained.
Caution
The power steering assist may be
reduced during an Autostop.
Conditions for an Autostop
The stop-start system checks if each
of the following conditions is fulfilled:
● The stop-start system is not manually deactivated.
● The bonnet is fully closed.
● The driver's door is closed or the driver's seat belt is fastened.
● The vehicle battery is sufficiently charged and in good condition.
● The engine is warmed up.
● The engine coolant temperature is not too high.
● The engine exhaust temperature is not too high, e.g. after driving
with high engine load.
● The ambient temperature is above -5 °C.
● The climate control system allows an Autostop.
● The brake vacuum is sufficient.
● The self-cleaning function of the diesel particle filter is not active.
● The vehicle was driven at least at
walking speed since the last
Autostop.
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Driving and operating139Otherwise an Autostop will be
inhibited.
Certain settings of the climate control
system may inhibit an Autostop. See
'Climate control' chapter for more
details 3 127.
Immediately after motorway driving,
an Autostop may be inhibited.
New vehicle running-in 3 136.
Vehicle battery discharge protection
To ensure reliable engine restarts,
several battery discharge protection
features are implemented as part of
the stop-start system.
Power saving measures
During an Autostop, several electrical
features such as auxiliary electric
heater or rear window heating are
disabled or switched to a power
saving mode. The fan speed of the
climate control system is reduced to
save power.
Restart of the engine by the driver
Depress the clutch pedal to restart the
engine.The engine start is indicated by the
needle at the idle speed position in
the tachometer.
If the selector lever is shifted out of
neutral before depressing the clutch
first, control indicator - illuminates
or is shown as a symbol in the Driver Information Centre.
Control indicator - 3 89.
Restart of the engine by the stop- start system
The selector lever must be in neutral to enable an automatic restart.
If one of the following conditions
occurs during an Autostop, the
engine will be restarted automatically
by the stop-start system:
● The stop-start system is manually deactivated.
● The bonnet is opened.
● The driver's seat belt is unfastened and the driver's door
is opened.
● The engine temperature is too low.● The charging level of the vehiclebattery is below a defined level.
● The brake vacuum is not sufficient.
● The vehicle is driven at least at walking speed.
● The climate control system requests an engine start.
● The air conditioning is manually switched on.
If the bonnet is not fully closed, a
warning message is displayed in the
Driver Information Centre.
If an electrical accessory, e.g. a
portable CD player, is connected to
the power outlet, a brief power drop
during restart might be noticeable.
Parking9 Warning
● Do not park the vehicle on an
easily ignitable surface. The
high temperature of the
exhaust system could ignite the
surface.
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140Driving and operating● Always apply the parkingbrake. Activate the manual
parking brake without pressing
the release button. Apply as
firmly as possible on a downhill
slope or uphill slope. Depress brake pedal at the same time to reduce operating force.
For vehicles with electric
parking brake, pull switch m for
approx. one second.
The electric parking brake is
applied when control indicator
m illuminates 3 89.
● Switch off the engine.
● If the vehicle is on a level surface or uphill slope, engage
first gear or set the selector
lever to position P before
removing the ignition key. On
an uphill slope, turn the front
wheels away from the kerb.
If the vehicle is on a downhill
slope, engage reverse gear or
set the selector lever to position P before removing the ignitionkey. Turn the front wheels
towards the kerb.
● Close the windows and the soft
top.
● Remove the ignition key. Turn the steering wheel until the
steering wheel lock is felt to
engage.
For vehicles with automatic
transmission, the key can only
be removed when the selector
lever is in position P.
● Lock the vehicle.
● Activate the anti-theft alarm system.
● The engine cooling fans may run
after the engine has been
switched off 3 188.
Caution
After running at high engine
speeds or with high engine loads,
operate the engine briefly at a low load or run in neutral for
approx. 30 seconds before
switching off, in order to protect
the turbocharger.
Notice
In the event of an accident with airbag deployment, the engine is
turned off automatically if the vehicle
comes to a standstill within a certain time.
Page 143 of 263

Driving and operating141Engine exhaust9Danger
Engine exhaust gases contain
poisonous carbon monoxide,
which is colourless and odourless and could be fatal if inhaled.
If exhaust gases enter the interior
of the vehicle, open the windows.
Have the cause of the fault
rectified by a workshop.
Avoid driving with an open load
compartment, otherwise exhaust
gases could enter the vehicle.
Diesel particle filter
The diesel particle filter system filters
harmful soot particles out of the
exhaust gases. The system includes
a self-cleaning function that runs
automatically during driving without
any notification. The filter is cleaned
by periodically burning off the soot
particles at high temperature. This
process takes place automatically
under set driving conditions and may
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 the cleaning of the filter is required
and if previous driving conditions did
not enable automatic cleaning, it will
be indicated by control indicator %.
Simultaneously Diesel partic. filter is
full continue driving appears in the
Driver Information Centre.
% 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 additionally a message appears in
the Driver Information Centre that
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.
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142Driving and operatingThe 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 3 177, 3 240 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.9 Warning
Avoid contact of your eyes or skin
with AdBlue.
In case of eye or skin contact,
rinse off with water.
Caution
Avoid contact of the paintwork with AdBlue.
In case of contact, rinse off with water.
AdBlue freezes at a temperature of
approx. -11 °C. As the vehicle is
equipped with an AdBlue pre-heater,
the emissions reduction at low
temperatures is ensured. The AdBlue
pre-heater works automatically.
The typical AdBlue consumption is
approx. two litres per 600 miles, but
can also be higher depending on
driving behaviour (e.g. high load or
towing).