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Driving and operating159
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.
Before 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
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. 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 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 is released.
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160Driving 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 the eco button.
Deactivation is indicated by the LED in the button extinguishing.
Autostop If the vehicle is at a low speed or 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.
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 steering assist can be
reduced during an Autostop.
Conditions for an Autostop
The stop-start system checks if each
of the following conditions is fulfilled.
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Driving and operating161
■ 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 3 150.
Immediately after motorway driving
an Autostop may be inhibited.
New vehicle running-in 3 158.
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.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 - 3 110.
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
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162Driving and operating
■ 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 engine restart may be
noticeable.
Parking ■ Do not park the vehicle on an easily
ignitable surface. The high
temperature of the exhaust system
could ignite the surface.
■ Always apply parking brake. Apply manual parking brake without
pressing release button. Apply as
firmly as possible on downhill or uphill slopes. Depress the footbrake at the same time to reduce
operating force.
Apply electric parking brake by pulling switch m for approx.
one second. Control indicator m
must illuminate.
■ Switch off the engine and ignition. Turn the steering wheel until the
steering wheel lock engages.
■ If the vehicle is on a level surface or
uphill slope, engage first gear or set the selector lever to P before
switching off the ignition. 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 theselector lever to P before switching
off the ignition. Turn the front
wheels towards the kerb.
■ Lock the vehicle and activate the anti-theft alarm system.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.
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Driving and operating163Engine 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 or warning
code 55 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 g illuminates additionally,
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.
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164Driving and operating
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 3 207, 3 274 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 (DEF) into the exhaust system.
The designation of the used DEF is
AdBlue Ⓡ 1)
. 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 approx.4000 mpg and depends on the driving
behaviour.
1) Registered trademark of the Verband der Automobilindustrie e.V. (VDA)
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Driving and operating165
If the AdBlue level falls below a
certain value, a level warning Exhaust
Fluid Range: 1500 mi will be
displayed in the Driver Information Centre (DIC).
A volume of at least 5 litres of AdBlue must be refilled soon.
Driving is possible without any
restrictions.
If AdBlue is not refilled within a certain
distance, further level warnings are
displayed in the DIC depending on
the current AdBlue level. The
warnings announce restrictions,
starting with limitations of the
maximum speed up to a prevention of an engine restart. The restrictions are
a legal requirement.
Before a limitation of the maximum
speed is activated with the next
restart, the warning messages
■ Exhaust Fluid Empty Refill Now
■ Max Speed Upon Restart 60 mph
are alternately displayed in the DIC.
Additionally the control indicator Y
illuminates continuously and a
warning chime sounds.
A speed limitation to 60 mph will be
activated with approx. 560 miles
exhaust fluid range remaining.
After a further limitation of the
maximum speed to 30 mph, a
prevention of the engine restart will be
announced.
Before the prevention of the engine
restart is activated, the warning
messages
■ Exhaust Fluid Empty Refill Now
■ Speed Limited to 30 mph
■ Engine Will Not Restart
are alternately displayed in the DIC.
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166Driving and operating
Additionally the control indicator Y
flashes continuously and a warning
chime sounds repeatedly.
To restart the engine, the tank must be filled with AdBlue first.
Refilling AdBlueCaution
Only use AdBlue that complies
with European standards
DIN 70 070 and ISO 22241-1.
Do not use additives.
Do not dilute AdBlue.
Otherwise the selective catalytic
reduction system could be
damaged.
Notice
Only use the designated AdBlue canisters for refilling to prevent a
topping up of too much AdBlue.
Additionally the fumes in the tank are captured in the canister and do not
emerge.
Since AdBlue has a limited
durability, check the date of expiry
before refilling.
Notice
A volume of at least 5 litres of AdBlue
must be added when refilling.
Otherwise the refilling of AdBlue
might not be detected by the system.
If AdBlue must be refilled at
temperatures below -11 °C, the
refilling of AdBlue might not be
detected by the system. In this case,
park the vehicle in a space with a
higher ambient temperature until
AdBlue is liquefied.
Notice
When unscrewing the protective cap from the filler neck, ammonia fumesmight emerge. Do not inhale as the
fumes have a pungent smell. The
fumes are not harmful by inhalation.
The vehicle must be parked on a level surface.
The filler neck for AdBlue is located
behind the fuel filler flap.
The fuel filler flap is located at right rear side of the vehicle.The fuel filler flap can only be opened
if the vehicle is unlocked.
1. Remove key from ignition lock.
2. Close all doors to avoid ammonia fumes entering the interior of the
vehicle.
3. Pull fuel filler flap at the recess and open 3 210.
4. Unscrew protective cap from the
filler neck.
5. Open AdBlue canister.
6. Mount one end of the hose on the
canister and screw the other end
on the filler neck.
7. Lift the canister until it is empty.