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Driving and operating183
■ Electronic Stability Control isoperating.
■ There is no traffic and nothing detected on the road sides for
several minutes. In this case there are no radar echoes and the sensor may report that it is blocked.
■ Collision imminent braking system is applying the brakes.
■ Radar sensor is blocked by an ice or water film.
■ A fault is detected in the radar, engine or brake system.
When adaptive cruise control is
deactivated automatically, the control
indicator m illuminates white and a
warning symbol is displayed as a pop- up in the Driver Information Centre.
The stored speed is maintained.
9 Warning
When adaptive cruise control is
deactivated, the driver must take
over full brake and engine control.
Switching off
Press C to switch off adaptive cruise
control. The control indicator m
extinguishes. The stored speed is
deleted.
Switching off the ignition also
switches off adaptive cruise control
and deletes the stored speed.
Driver's attention
■ Use adaptive cruise control carefully on bends or mountainroads, as it can lose the vehicle
ahead and require time to detect it
again.
■ Do not use the system on slippery roads as it can create rapid
changes in tyre traction (wheel spinning), so that you could lose
control.
■ Do not use adaptive cruise control during rain, snow or heavy dirt, as
the radar sensor can be covered by
a water film, dust, ice or snow. This
reduces or completely suppresses
the visibility. In case of sensor
blockage, clean the sensor cover.
System limits ■ The system's automatic brake force
does not permit hard braking and
the braking level may not be
sufficient to avoid a collision.
■ After a sudden lane change, the system needs a certain time to
detect the next preceding vehicle.
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Driving and operating185
Hill and trailer considerations
System performance on hills and
when towing a trailer depends on
vehicle speed, vehicle load, traffic
conditions and the road gradient. It
may not detect a vehicle in your path
while driving on hills. On steep hills,
you may have to use the accelerator
pedal to maintain your vehicle speed.
When going downhill, especially
when towing a trailer, you may have
to brake to maintain or reduce your
speed.
Note that applying the brake
deactivates the system. It is not
recommended to use adaptive cruise
control on steep hills especially when towing a trailer.
Radar unit
The radar unit is mounted behind the
radiator grille below the brand
emblem.
9 Warning
The radar unit was aligned
carefully during manufacture.
Therefore, after a frontal accident, do not use the system. The front
bumper may appear to be intact,
however the sensor behind can be
out of position and react
incorrectly. After an accident,
consult a workshop to verify and
correct the adaptive cruise control
sensor position.
Settings
Settings can be changed in the Auto
collision preparation menu in the
vehicle personalisation 3 129.
Fault
If the adaptive cruise control does not
work due to temporary conditions
(e.g. blockage by ice) or if there is a
permanent system error, then a
message is displayed in the Driver
Information Centre.
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Driving and operating189
Deactivation
The system can be deactivated.
Press V repeatedly until the following
message appears in the Driver
Information Centre.
General information for both
variants of forward collision alert
9 Warning
Forward collision alert is just a
warning system and does not
apply the brakes. When
approaching a vehicle ahead too
rapidly, it may not provide you
enough time to avoid a collision.
The driver accepts full
responsibility for the appropriate
following distance based on traffic, weather and visibility conditions.
The complete attention of the
driver is always required while
driving. The driver must always be
ready to take action and apply the
brakes.
System limitations
The system is designed to warn only for vehicles, but may react also onother metallic objects.
In the following cases, forward
collision alert may not detect a vehicle ahead or sensor performance is
limited:
■ on winding roads
■ when weather limits visibility, such as fog, rain, or snow
■ when the sensor is blocked by snow, ice, slush, mud, dirt, or
windscreen damage
Following distance
indication
The following distance indication
displays the distance to a preceding
moving vehicle. The system uses,
depending on the vehicle equipment,
either the radar behind the radiator
grille or the front camera in the
windscreen to detect the distance of
a vehicle directly ahead in your lane.
It is active at speeds above 25 mph.
When a preceding vehicle is detected ahead, the distance is indicated inseconds, displayed on a page in the
Driver Information Centre 3 117.
Press MENU on the turn signal lever
to select Vehicle Information Menu
X and turn the adjuster wheel to
choose following distance indication
page.
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Driving and operating191
results immediately in a strong
braking. This function helps the driver brake quicker and stronger before theimminent collision.9 Warning
Active emergency braking is not
designed to apply strong
autonomous braking or to avoid automatically a collision. It is
designed to reduce the vehicle
speed before collision. It may not
react on stopped vehicles,
pedestrians or animals. After a
sudden lane change, the system
needs a certain time to detect the
next preceding vehicle.
The complete attention of the
driver is always required while
driving. The driver shall always be ready to take action and apply the brakes and steer to avoid
collisions. The system is designed
to work with all occupants wearing their seat belts.
System limitations
The active emergency braking has
limited or no function during rain,
snow or heavy dirt, as the radar
sensor can be covered by a water
film, dust, ice or snow. In case of
sensor blockage, clean the sensor
cover.
In some seldom cases the active
emergency braking system may
provide a short automatic braking in
situations that seem to be
unnecessary, for instance due to
traffic signs in a curve or due to
vehicles in another lane. This is
acceptable operation, the vehicle
does not need service. Firmly apply
the accelerator pedal to override the
automatic braking.
Settings Settings can be changed in the Auto
collision preparation menu in the
vehicle personalisation, 3 129.
Fault
In the event of a system service
requirement, a message is displayed
in the Driver Information Centre.
If the system does not work as it
should, vehicle messages are
displayed in the Driver Information
Centre.
Vehicle messages 3 123.
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Driving and operating209
Pressing Y switches between petrol
and natural gas operation. Switching
is not possible at high loads (e.g.
strong acceleration, running at full
throttle). The LED status shows the
current operating mode.1 off=natural gas
operation1 illumi‐
nates=petrol operation1 flashes=no switching is
possible, one type of
fuel is empty
As soon as the natural gas tank is empty, petrol operation is
automatically engaged until the
ignition is switched off.
If the natural gas tank is not refuelled, the system must be manually
switched to petrol operation before
the engine is started-up again. This
will prevent damage to the catalytic
converter (overheating caused by
irregular fuel supply).
If the selector switch is operated
several times within a short time, a
switchover block is activated. The
engine remains in the current
operating mode. The block remains
active until the ignition is switched off.
A slight loss of power and torque can be expected during petrol operation.
You must therefore adapt your driving
style (e.g. during overtaking
manoeuvres) and vehicle loads (e.g.
towing loads) accordingly.
Every six months run the petrol tank
down until control indicator Y
illuminates, then refuel. This is
necessary to maintain fuel quality as
well as system function necessary for
petrol operation.
Fill the tank completely at regular intervals to prevent corrosion in the
tank.Refuelling9 Danger
Before refuelling, switch off engine
and any external heaters with
combustion chambers. Switch off
any mobile phones.
Follow the operating and safety
instructions of the filling station
when refuelling.
Page 212 of 299
210Driving and operating9Danger
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 the vehicle.
The fuel filler flap can only be opened
if the vehicle is unlocked. Release the
fuel filler flap by pushing the flap.
Petrol and Diesel refuelling
To open, turn the cap slowly anti-
clockwise.The fuel filler cap can be retained in
the bracket on the fuel filler flap.
For refuelling, fully insert the pump
nozzle and switch it on.
After automatic cut-off, it can be
topped up with max. two doses of fuel.
Caution
Wipe off any overflowing fuel
immediately.
To close, turn the fuel filler cap
clockwise until it clicks.
Close the flap and let engage.
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Driving and operating211
Vehicles with misfuel inhibitor9Warning
Do not try to open the flap of the
fuel filler neck manually on
vehicles with misfuel inhibitor.
Disregarding this could lead to
trapping of the fingers.
Vehicles with a selective catalytic
reduction system are equipped with a
misfuel inhibitor.
The misfuel inhibitor ensures that the flap of the fuel filler neck can only be
opened by using a nozzle for diesel
fuel or a funnel for emergency
refilling.
Turn the fuel filler cap slowly anti-
clockwise.
The cap can be retained in the
bracket on the fuel filler flap.
Place the nozzle in straight position to
the filler neck and press with slight
force to insert.
In case of an emergency refilling with a canister, a funnel must be used to
open the cap of the filler neck.The funnel is located on the right side storage in the load compartment.
Place the funnel in straight position to
the filler neck and press with slight
force to insert.
Use the funnel to fill in the diesel fuel
into the filler neck.
After topping-up, put the funnel into
the plastic bag and stow it in the
storage compartment.
Selective catalytic reduction system
3 163.
Natural gas refuelling
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212Driving and operating
The fuel filler flap can only be opened
if the vehicle is unlocked. Release the
fuel filler flap by pushing the flap.9 Warning
Refuel only with a maximum
output pressure of 250 bar. Use
only temperature compensated
filling stations.
The refuelling procedure must be
completed, i.e. the filler neck must be
vented.
The capacity of the natural gas tank depends on outside temperature,
filling pressure and type of refuelling
system. Capacities 3 284.
Close the flap and allow it to engage. Terms for "natural gas vehicles"
abroad:
GermanErdgasfahrzeugeEnglishNGVs = Natural Gas Vehi‐
clesFrenchVéhicules au gaz naturel -
or - Véhicules GNVItalianMetano auto
Terms for "natural gas" abroad:
GermanErdgasEnglishCNG = Compressed
Natural GasFrenchGNV = Gaz Naturel (pour)
Véhicules - or -
CGN = carburantgaz
naturelItalianMetano (per auto)
Liquid gas refuelling
Follow the operating and safety
instructions of the filling station when
refuelling.
The filling valve for the liquid gas is
behind the fuel filler cap.
Unscrew protective cap from the filler neck.
Screw the required adapter hand-
tight onto the filler neck.