138Driving and operatingStarting 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.
Automatic Starter Control
This function controls the engine
starting procedure. The driver does
not need to hold the key in position 3
or to hold Engine Start/Stop pressed.
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 depressed (manual transmission).
● Brake pedal not depressed 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 battery sensor ensures
that an Autostop is only performed if
the 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.
142Driving and operatingDiesel particle filterAutomatic 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 beindicated 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.
Driving and operating143Caution
Fuel grades other than those listedon pages 3 166, 3 225 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.
Automatic transmission
The automatic transmission permits
automatic gearshifting (automatic
mode) or manual gearshifting
(manual mode).
Transmission display
The mode or selected gear is shown
in the Driver Information Centre.
In automatic mode, the driving
programme is indicated by D.
In manual mode, M and the number
of the selected gear is indicated.
R indicates reverse gear.
N indicates neutral position.
P indicates park position.
Selector leverP:park position, wheels are locked, engage only when the vehicle is
stationary and the parking brake
is appliedR:reverse gear, engage only when
the vehicle is stationaryN:neutralD:automatic modeM:manual mode<:upshift in manual mode]:downshift in manual mode
Driving and operating145Gear shift indication
The symbol R with a number beside
it is indicated when gearshifting is
recommended for fuel saving
reasons.
Shift indication appears only in
manual mode.
Electronic driving programmes
● Following a cold start, the operating temperature
programme increases engine
speed to quickly bring the
catalytic converter to the required
temperature.
● The automatic neutral shift function automatically shifts to
idling when the vehicle is stopped
with a forward gear engaged and the brake pedal is pressed.
● Special programmes automatically adapt the shifting
points when driving up inclines or
down hills.Automatic transmission
adaptation feature
This feature adapts transmission
operation during constant driving or
gear shifting. It increases durability
and keeps best shift quality over the
life cycle. You may perceive shifting
at initial mileage as uncomfortable,
but this is normal. Shift quality will be
improved gradually by constant
driving at each gear and gear shifting.
Kickdown If the accelerator pedal is presseddown completely in automatic mode, the transmission shifts to a lower gear
depending on engine speed.
Fault
In the event of a fault, a vehicle message is displayed in the Driver
Information Centre. Vehicle
messages 3 103.
The transmission no longer shifts
automatically. Continued travel is possible with manual shifting.Only the highest gear is available.
Depending on the fault, second gear
may also be available in manual
mode. Shift only when vehicle is at a
standstill.
Have the cause of the fault remedied
by a workshop.
Interruption of power supply In the event of an interruption of
power supply, the selector lever
cannot be moved out of the P
position. The ignition key cannot be
removed from the ignition switch.
If the battery is discharged, start the
vehicle using jump leads 3 210.
If the battery is not the cause of the fault, release the selector lever.
1. Keep the brake pedal depressed and pull the parking brake lever
up.
166Driving and operatingDeactivation
The system is deactivated by
pressing ), the LED in the button
extinguishes.
At speeds below 56 km/h the system
is inoperable.
Fault
The lane departure warning system
may not operate properly when:
● the windscreen is not clean
● there are adverse environmental conditions like heavy rain, snow,
direct sunlight or shadows
The system can not operate when no
lane marking is detected.Fuel
Fuel for petrol engines Only use unleaded fuel that complies
with European standard EN 228 or
E DIN 51626-1 or equivalent.
The engine is capable of running with
fuel that contains up to 10% ethanol
(e.g. named E10).
Use fuel with the recommended
octane rating. A lower octane rating
can reduce engine power and torque
and slightly increases fuel
consumption.Caution
Do not use fuel or fuel additives
that contain metallic compounds
such as manganese-based
additives. This may cause engine
damage.
Caution
Use of fuel that does not comply to EN 228 or E DIN 51626-1 or
equivalent can lead to deposits or
engine damage.
Caution
Use of fuel with a lower octane
rating than the lowest possible
rating could lead to uncontrolled combustion and engine damage.
The engine-specific requirements
regarding octane rating are given in
the engine data overview 3 225. A
country-specific label at the fuel filler
flap can supersede the requirement.
Fuel for diesel engines Only use diesel fuel that complies
with EN 590.
In countries outside the European
Union use Euro-Diesel fuel with a
sulphur concentration below 50 ppm.
Driving and operating167Caution
Use of fuel that does not comply toEN 590 or similar can lead to
engine powerloss, increased wear
or engine damage.
Do not use marine diesel oils, heating
oils, Aquazole and similar diesel-
water emulsions. Diesel fuels must
not be diluted with fuels for petrol
engines.
Fuel for liquid gas operation Liquid gas is known as LPG
(Liquefied Petroleum Gas) or under its French name GPL (Gaz de Pétrole
Liquéfié). LPG is also known as
Autogas.
LPG consists mainly of propane and
butane. The octane rating is between 105 and 115, depending on the
butane proportion. LPG is stored as a
liquid at a pressure of approx. five to
ten bar.
The boiling point depends on the
pressure and the mixing ratio. At
ambient pressure, it is between
-42 °C (pure propane) and -0.5 °C
(pure butane).Caution
The system works at an ambient
temperature of approx. -8 °C to
100 °C.
Full functioning of the LPG system can only be guaranteed with liquid
gas which complies with the minimum
requirements of DIN EN 589.
Fuel selector
Pressing LPG switches between
petrol and liquid gas operation as
soon as the required parameters (coolant temperature, gas
temperature and minimum engine
speed) have been reached. The
requirements are usually fulfilled after
approx. 60 seconds (depending on
exterior temperature) and the first firm press on the accelerator. The status
LED shows the current operating
mode.LED off:petrol operationLED
flashes:checking conditions for
fuel transition to liquid
gas operation.
Illuminates if conditions
are fulfilled.LED illu‐
minates:liquid gas operationLED
flashes
five
times
and
extin‐
guishes:liquid gas tank is empty
or failure in liquid gas
system. A message is
displayed in the Driver
Information Centre.
If the fuel tank is empty, the engine
will not start.
168Driving and operatingThe selected fuel mode is stored andreactivated at the next ignition cycle if
conditions allow.
As soon as the liquid gas tanks are
empty, petrol operation is
automatically engaged until the
ignition is switched off.
When switching automatically
between petrol or gas operation, a
brief delay of engine tractive power
may be noticeable.
Every six months, run the petrol tank
down until control indicator Y
illuminates, then refuel. This helps
maintain fuel quality and system
function for petrol operation.
Fill the tank completely at regular
intervals to prevent corrosion in the
tank.
Faults and remedies
If gas mode is not possible, check the following:
● Is there enough liquid gas present?
● Is there enough petrol present for
starting?Due to extreme temperatures in
combination with the gas
composition, it may take slightly
longer before the system switches
from petrol to gas mode.
In extreme situations, the system may
also switch back to petrol mode if the
minimum requirements are not
fulfilled. If conditions allow, it may be possible to manually switch back to
liquid gas operation.
Seek the assistance of a workshop in
the event of all other faults.Caution
Repairs and adjustments may only be made by trained specialists in
order to maintain the safety and
warranty on the LPG system.
Liquid gas is given a particular odour
(odorised) so that any leaks can be
detected easily.
9 Warning
If you smell gas in the vehicle or in
the immediate vicinity, switch to petrol mode immediately. No
smoking. No naked flames or
ignition sources.
If the gas odour persists, do not start
the engine. Have the cause of the
fault remedied by a workshop.
When using underground car parks,
follow the instructions of the operator
and local laws.
Note
In the event of an accident, switch off
the ignition and lights.
Driving and operating169Refuelling9Danger
Before refuelling, switch off
ignition and any external heaters
with combustion chambers.
Follow the operating and safety
instructions of the filling station
when refuelling.
9 Danger
Fuel is flammable and explosive.
No smoking. No naked flames or
sparks.
If you can smell fuel in your
vehicle, have the cause of this
remedied immediately by a
workshop.
Caution
In case of misfuelling, do not
switch on ignition.
Fuel filler flap is located at right rear
side of vehicle.
The fuel filler flap can only be opened
if the vehicle is unlocked. Push flap
and open.