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Driving and operating1359Warning
If the vehicle battery is discharged,
the vehicle must not be towed,
tow-started or jump-started as the
steering wheel lock cannot be
disengaged.
Operation on vehicles with
electronic key system in case of
failure
If either the electronic key fails or the
battery of the electronic key is weak,
the Driver Information Centre may
display No Remote Detected or
Replace Battery in Remote Key when
you try to start the vehicle.
Hold the electronic key with buttons outside at the marking on the steering column cover as shown in the
illustration.
Depress the clutch pedal (manual
transmission) or the brake pedal
(automatic transmission or manual
transmission automated) and press
Start/Stop button to start the engine.
This option is intended for
emergencies only. Replace the
electronic key battery as soon as
possible 3 24.
For unlocking or locking the doors,
see fault in radio remote control unit
or electronic key system 3 25.
Power saving mode
This function manages the duration of
using certain systems to avoid
discharging of the vehicle battery.
After the engine has stopped, some
systems can still be used such as the audio and telematics system,
windscreen wipers, dipped beam
headlamps, courtesy lamps, etc. for a total maximum time of about forty
minutes.
Changing into power saving
mode
When a certain discharging status of
the vehicle battery is achieved, the
active functions are switched in
standby mode. A message appears in the Driver Information Centre
indicating Power saving mode .
A telephone call being made at this
time will be maintained for around 10
minutes with the Bluetooth handsfree
system of the Infotainment system.
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136Driving and operatingDeactivating power saving mode
Standby mode is reactivated
automatically next time the vehicle is
driven. To use the functions
immediately, start the engine:
● for less than ten minutes to use the systems for approximately
five minutes
● for more than ten minutes to use the systems for up to
approximately thirty minutes.
Have the engine run for the duration
specified to ensure that the battery
charge is sufficient. Do not repeatedly and continuously restart the engine in
order to charge the battery.Starting the engine
Vehicles with ignition switch
Turn key to position 1 to release the
steering wheel lock.
Manual transmission: operate clutch
and brake pedal.
Automatic transmission: operate
brake pedal and move selector lever
to P or N.
Do not operate accelerator pedal.
Diesel engines: wait until control
indicator ! extinguishes.
Turn key briefly to position 2 and
release after the engine has been
started.
Manual transmission: during an
Autostop, the engine can be started
by depressing the clutch pedal
3 138.
Automatic transmission: during an
Autostop, the engine can be started
by releasing the brake pedal 3 138.
Vehicles with power button
Manual transmission: operate clutch
and brake pedal.
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Driving and operating137Automatic transmission: operate
brake pedal and move selector lever
to P or N.
Do not operate accelerator pedal.
Press and release Start/Stop: an
automatic procedure operates the
starter with a short delay until the engine is running.
Before restarting or to switch off the
engine when vehicle is stationary, press Start/Stop once more briefly.
Manual transmission: during an
Autostop, the engine can be started
by depressing the clutch pedal
3 138.
Automatic transmission: during an
Autostop, the engine can be started
by releasing the brake pedal 3 138.
Emergency shut off during driving If the engine needs to be switched offduring driving in case of emergency,
press Start/Stop for five seconds.9Danger
Switching off the engine during
driving may cause loss of power
support for brake and steering
systems. Assistance systems and
airbag systems are disabled.
Lighting and brake lights will
extinguish. Therefore power down the engine and ignition while
driving only when required in case of emergency.
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 requires a
warming phase of approx.
five minutes. The selector lever must
be in position P.
Heating functionalities
Note
Individual heating functionalities,
such as heated seats or heated
steering wheel, may be temporarily
unavailable in the event of electrical
loading constraints. Functions will
be resumed after some minutes.
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.
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138Driving and operatingStop-start systemThe 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.
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.
DeactivationDeactivate the stop-start system
manually by pressing Ò. The
deactivation is indicated when the
LED in the button illuminates.
AutostopVehicles with manual transmission
An Autostop can be activated at a
standstill.
Activate an Autostop as follows: ● Depress the clutch pedal.
● Set the lever to neutral.
● Release the clutch pedal.
The engine will be switched off while
the ignition stays on.Vehicles with automatic transmission If the vehicle is at a standstill with
depressed brake pedal, Autostop is
activated automatically.
The engine will be switched off while the ignition stays on.
The stop-start system will be disabled
on inclines.Indication
An Autostop is indicated by control
indicator D.
During an Autostop, the heating and
brake performance will be
maintained.
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 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.
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Driving and operating139● The engine exhaust temperatureis not too high, e.g. after driving
with high engine load.
● The ambient temperature is sufficient.
● The climate control system allows an Autostop.
● The brake vacuum is sufficient.
● The self-cleaning function of the diesel particle filter is not active.
Otherwise an Autostop will be
inhibited.
Certain settings of the climate control
system may inhibit an Autostop. See
Climate control chapter for more
details 3 121.
If an autostop is temporarily not
available, D flashes green 3 95.
Immediately after driving at a higher
speed an Autostop may be inhibited.
New vehicle running-in 3 133.
Vehicle battery discharge protection
To ensure reliable engine restarts, several vehicle 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
Vehicles with manual transmissionConventional restart
All engines have conventional restart.
Depress the clutch pedal without
depressing the brake pedal to restart
the engine.
On engines with late restart a
conventional restart is only possible
without depressed brake pedal.
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 driver's seat belt is unfastened or the driver's door is
opened.
● The engine temperature is too low.
● The charging level of the vehicle battery is below a defined level.
● The brake vacuum is not sufficient.
● The climate control system requests an engine start.
● The air conditioning is manually switched on.
If an electrical accessory, e.g. a
portable CD player, is connected to
the power outlet, a brief power drop
during the restart might be noticeable.
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140Driving and operatingParking9Warning
● Do not park the vehicle on an
easily ignitable surface. The
high temperature of the
exhaust system could ignite the
surface.
● Always apply the parking brake. 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.
● 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 or
switching off ignition on
vehicles with power button. 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 ignition
key or switching off ignition on
vehicles with power button.
Turn the front wheels towards
the kerb.
● Close the windows.
● Remove the ignition key from the ignition switch or switch off
ignition on vehicles with power
button. Turn the steering wheel until the steering wheel lock is
felt to engage.
● Lock the vehicle.
● Activate the anti-theft alarm system.
● The engine cooling fans may run
after the engine has been
switched off 3 187.
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.
Note
In the event of an accident with
airbag deployment, the engine is
switched off automatically if the
vehicle comes to a standstill within a
certain time.
Emergency operation under
extreme cold temperatures
9 Warning
This emergency operation may
only be carried out in case of
extremely cold temperatures and if the vehicle is parked on a levelsurface.
In countries with extreme cold
temperatures it may be necessary to
park the vehicle without applied
parking brake.
This is an emergency operation to
avoid freezing of the parking brake.
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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
Automatic cleaning process
The diesel particle filter system filters
harmful soot particles out of the
exhaust gases.
The start of saturation of the particle
filter is indicated by the temporary illumination of % or H ,
accompanied by a message in the
Driver Information Centre.
As soon as the traffic conditions
permit, regenerate the filter by driving at a vehicle speed of at least 60 km/huntil the control indicator
extinguishes.
Note
On a new vehicle, the first particle
filter regeneration operations may
be accompanied by a burning smell,
which is normal. Following
prolonged operation of the vehicle at
very low speed or at idle, you may,
in exceptional circumstances, notice the emission of water vapour at the
exhaust on acceleration. This does
not affect the behaviour of the
vehicle or the environment.
Cleaning process not possible
If % or H stays on, accompanied
by an audible signal and a message,
this indicates that the particle filter
additive level is too low.
The reservoir must be topped-up
without delay. Seek the assistance of
a workshop.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, 3 233 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.
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142Driving and operatingAdBlue
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 (DEF) 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.
Level warnings
The AdBlue consumption is
approximately 0.7 litres per 1000 km.
The consumption can be higher
depending on driving behaviour (e.g.
high load or towing).
Depending on the calculated range of AdBlue, different messages are
displayed in the Driver Information
Centre. The messages and the
restrictions are a legal requirement.
The first possible warning message appears at an AdBlue range below
2400 km, shows up at each start and each 300 km range reduction:
Top up AdBlue: Starting impossible in 2400 km
Additionally, control indicator Y
illuminates continuously and a chime
sounds with every message pop-up.
At an AdBlue range below 600 km,
the following warning message is
being displayed, shows up at each
start and each 20 km range reduction:
Top up AdBlue: Starting impossible in 600 km
Additionally, control indicator Y
flashes continuously and a chime
sounds with every message pop-up.
Note
In case of high AdBlue consumption,
the Driver Information Centre may
display this warning without the
previous warning stages.
The last warning level is entered
when the AdBlue tank is empty.
Restart of the engine is not possible.