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Driving and operating151Driving hints
Control of the vehicle
Never coast with engine not
running
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.
Stop-start system 3 154.
Idle boost
If charging of the vehicle battery is
required due to battery condition, the
power output of the generator must
be increased. This will be achieved by an idle boost which may be audible.
A message appears 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 3 114.Starting 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 of the vehicle battery.
Diesel particle filter 3 157.
Ignition switch positions Turn key:
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152Driving and operating0:ignition off: Some functions
remain active until key is
removed or driver's door is
opened, provided the ignition was
on previously1:accessory power mode: Steering wheel lock released, some
electrical functions are operable,
ignition is off2:ignition on power mode: Ignition
is on, diesel engine is preheating.
Control indicators illuminate and
most electrical functions are
operable3:engine start: Release key after
starting procedure beginsSteering wheel lock
Remove key from ignition switch and
turn steering wheel until it engages.9 Danger
Never remove the key from
ignition switch during driving as
this will cause steering wheel lock.
Retained power off
The following electronic systems can
work until the driver's door is opened
or for ten minutes after the ignition is
switched off:
● power windows
● power outlets
Starting the engine
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 the accelerator pedal. Diesel engines: turn the key to
position 2 for preheating and wait until
control indicator ! extinguishes.
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Driving and operating153Turn key briefly to position 3 and
release: an automatic procedure
operates the starter with a short delay
until the engine is running, see
Automatic Starter Control.
Manual transmission: during an
Autostop, the engine can be started
by depressing the clutch pedal
3 154.
Automatic transmission: during an
Autostop, the engine can be started
by releasing the brake pedal 3 154.
Before restarting or to switch off the
engine, turn the key back to position
0 .9 Danger
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
The start of 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 battery.
With temperatures below -30 °C the
automatic transmission need a
warming phase of approx. five
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 engine
is 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.
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154Driving 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. 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.Deactivation
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.
Indication
An Autostop is indicated by the
needle at the AUTOSTOP position in
the tachometer.
After restart, the idle speed is
indicated.
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.
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Driving and operating155● The stop-start system is notmanually 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.
Otherwise an Autostop will be
inhibited.Certain settings of the climate control
system may inhibit an Autostop. See
Climate control chapter for more
details 3 144.
Immediately after motorway driving,
an Autostop may be inhibited.
New vehicle running-in 3 151.
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 into 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.
When the engine is restarted, control
indicator D in the Driver Information
Centre extinguishes.If the selector lever is shifted out of
neutral before depressing the clutch
pedal first, control indicator -
illuminates or is shown as a message
in the Driver Information Centre.
Control indicator - 3 112.
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 charge level of the vehicle battery is below a defined level.
● The brake vacuum is not sufficient.
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156Driving and operating● The vehicle is driven at least atwalking 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 engine restart may 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.
● 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.
For vehicles with electric
parking brake, pull switch m for
a minimum of one second until
control indicator m illuminates
constantly and electric parking
brake is applied 3 112.
● 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 ignition
key. Turn the front wheels
towards the kerb.● Close the windows.
● Remove the ignition key from the ignition switch. 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 3 215.
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.
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Driving and operating157Note
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.Engine exhaust9 Danger
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 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 seven and twelve
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.
System requires manual cleaning
process
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
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158Driving and operatingindicated by % and a warning
message in the Driver Information
Centre.
% with a warning message
illuminates when diesel particle filter
is full. Start cleaning process as soon
as possible.
% with a warning message flashes
when diesel particle filter has reached the maximum filling level. Start
cleaning process immediately to
avoid damage to the engine.
Activate manual 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.
Cleaning takes place quickest at high
engine speeds and loads.
The control indicator % extinguishes
as soon as the self-cleaning
operation is complete. Keep on
driving until self-cleaning operation is
complete.Caution
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 3 198, 3 267 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.