Driving and operating187Brake preparation system
When approaching a vehicle ahead
so quickly that a collision is likely, the brake preparation system slightlypressurises the brakes. This reduces
the response time, when a manual or automatic braking is requested.
The brake system is prepared so that braking can occur more rapidly.
Emergency automatic braking
After the brake preparation and just
before the imminent collision, this
function automatically applies limited
braking to reduce the impact speed of
the collision.
Forward looking brake assist
In addition to brake preparation
system and emergency automatic
braking, the forward looking brake
assist function makes the brake assist more sensitive. In this way,
depressing the brake pedal slightly
results immediately in a strong
braking. This function helps the driver
brake quicker and stronger before the imminent 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
vehicle personalisation menu in the
Info-Display.
Select the relevant setting in
Settings in the Info-Display.
Vehicle personalisation 3 125.
Fault
In the event of a system service
requirement, a message is displayed
in the Driver Information Centre.
Driving and operating191mirror, when detecting objects that
may not be visible in the interior and
exterior mirrors.
The system's sensors are located in
the bumper on the left and right side
of the vehicle.9 Warning
Side blind spot alert does not
replace driver vision.
The system does not detect:
● vehicles outside the side blind zones which may be rapidly
approaching
● pedestrians, cyclists or animals
Before changing a lane, always
check all mirrors, look over the
shoulder and use the turn signal.
When the system detects a vehicle in the side blind zone while driving
forward, either while passing a
vehicle or being passed, a yellow
warning symbol B will illuminate in
the relevant exterior mirror. If the
driver then activates the turn signal,
the warning symbol B starts flashing
yellow as a warning not to change
lanes.
Note
If the passing vehicle is at least
10 km/h faster than the passed
vehicle, the warning symbol B in the
relevant exterior mirror may not
illuminate.
Side blind spot alert is active from
speeds of 10 km/h up to 140 km/h.
Driving faster than 140 km/h
deactivates the system, indicated by
low lighting warning symbols B in
both exterior mirrors. Reducing the speed again will extinguish the
warning symbols. If a vehicle is then
detected in the blind zone, the
warning symbols B will illuminate as
normal on the relevant side.
When the vehicle is started, both exterior mirror displays will briefly
illuminate to indicate that the system
is operating.
The system can be activated or
deactivated in the Info-Display,
vehicle personalisation 3 125.
Deactivation is indicated by a
message in the Driver Information
Centre.
Detection zones
The detection zones start at the rear
bumper and extend approx.
three metres rearwards and to the
sides. The height of the zone is
approx. between half a metre and
two metres off the ground.
Side blind spot alert is designed to
ignore stationary objects, e.g.
guardrails, posts, curbs, walls and
beams. Parked vehicles or oncoming
vehicles are not detected.
194Driving and operatingFault
Fault messages are displayed with a 9 on the top line of the Info-Display.
The rear view camera may not
operate properly when:
● The surrounding area is dark.● The sun or the beam of headlights is shining directly into
the camera lens.
● Ice, snow, mud, or anything else covers the camera lens. Clean
the lens, rinse it with water, and
wipe it with a soft cloth.
● The tailgate is not closed correctly.
● The vehicle had a rear-end accident.
● There are extreme temperature changes.Traffic sign assistant
Functionality
The traffic sign assistant system
detects designated traffic signs via a
front camera and displays them in the
Driver Information Centre.
Traffic signs which will be detected
are:
Limit and no passing signs ● speed limit
● no passing
● end of speed limit
● end of no passingRoad signs
beginning and end of:
● city regions (country specific)
● motorways
● A-roads
● play streetsAdd-on signs ● additional hints to traffic signs
● restriction of trailer towing
● tractor constraints
● wet warning
● ice warning
● direction arrows
Speed limit signs are displayed in the
Driver Information Centre until the
next speed limit sign or end of speed
limit is detected or up to a defined sign timeout.
Driving and operating197Reasons for signs being cleared:● A predefined distance was driven
or time has elapsed (differs for
each sign type)
● Vehicle drives through a turn
● The speed becomes slower than 52 km/h (city entry detection)
Fault
The traffic sign assistant system may
not operate correctly if:
● The area of the windscreen, where the front camera is
located, is not clean or affected
by foreign items, e.g. stickers.
● Traffic signs are completely or partially covered or difficult to
discern.
● There are adverse environmental
conditions, e.g. heavy rain, snow,direct sunlight or shadows.
● Traffic signs are incorrectly mounted or damaged.
● Traffic signs do not comply with the Vienna Convention on traffic
signs (Wiener Übereinkommen
über Straßenverkehrszeichen).Caution
The system is intended to help the driver within a defined speed
range to discern certain traffic
signs. Do not ignore traffic signs
which are not displayed by the
system.
The system does not discern any other than the conventional traffic
signs that might give or end a
speed limit.
Do not let this special feature
tempt you into taking risks when
driving.
Always adapt speed to the road
conditions.
The driver assistance systems do not relieve the driver from full
responsibility for vehicle
operation.
Lane departure warning
The lane departure warning system
observes the lane markings between
which the vehicle is driving via a front camera. The system detects lane
changes and warns the driver in the
event of an unintended lane change
via visual and acoustic signals.
Criteria for the detection of an
unintended lane change are:
● No operation of turn signals.
● No brake pedal operation.
● No active accelerator operation or speeding-up.
● No active steering.
If the driver is active, no warning will
be issued.
Activation
198Driving and operatingThe lane departure warning system isactivated by pressing ). The
illuminated LED in the button
indicates that the system is switched
on. When the control indicator ) in
the instrument cluster illuminates
green, the system is ready to operate.
The system is only operable at
vehicle speeds above 56 km/h and if
lane markings are available.
When the system recognises an
unintended lane change, the control
indicator ) changes to yellow and
flashes. Simultaneously a chime
sound is activated.
Deactivation
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.
202Driving and operating9Warning
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.
Refuelling9 Danger
Before refuelling, switch off
ignition and any external heaters
with combustion chambers.
Switch off any mobile phones.
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 the vehicle.
204Driving and operatingThe misfuel inhibitor ensures that theflap 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
anticlockwise.
The cap can be retained in the
bracket on the fuel filler flap.
Place the nozzle in a straight line to the filler neck and press with slight
force to insert.
In case of an emergency, refill with a
canister. A funnel must be used to
open the cap of the filler neck.The funnel is located on the right-
hand side storage compartment in the load compartment.
Place the funnel in a straight line to
the filler neck and press with slight force to insert.
Use the funnel to fill 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
3 159.
Natural gas refuellingThe 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 3 272.
Close the flap and allow it to engage. Terms for "natural gas vehicles"
abroad:
Vehicle care239If w illuminates at lower temperatures
and extinguishes after some driving,
this could be an indicator for
approaching a low tyre pressure
condition. Check tyre pressure.
Vehicle messages 3 123.
If the tyre pressure must be reduced
or increased, switch off ignition.
Only mount wheels with pressure
sensors, otherwise the tyre pressure
will not be displayed and w
illuminates continuously.
A temporary spare wheel is not
equipped with pressure sensors. The
tyre pressure monitoring system is
not operational for these wheels.
Control indicator w illuminates. For
the further three wheels the system remains operational.
The use of commercially available
liquid tyre repair kits can impair the
function of the system. Factory-
approved repair kits can be used.
Operating electronic devices or being
close to facilities using similar wave
frequencies could disrupt the tyre
pressure monitoring system.Each time the tyres are replaced, tyre pressure monitoring system sensors
must be dismounted and serviced.
For the screwed sensor: replace
valve core and sealing ring. For
clipped sensor: replace complete
valve stem.
Vehicle loading status
Adjust tyre pressure to load condition according to the tyre information label
or tyre pressure chart 3 273, and
select the appropriate setting in the Tyre load menu in the Driver
Information Centre 3 117. This
setting is the reference for the tyre
pressure warnings.
The Tyre load menu only appears if
the vehicle is at a standstill and the
parking brake is applied. On vehicles
with automatic transmission the
selector lever has to be in P.
Select Tyre load page under Vehicle
Information Menu ? in the Driver
Information Centre 3 117.
Select: ● Light for comfort pressure up to
3 people.
● Eco for Eco pressure up to
3 people.
● Max for full load.
Tyre pressure sensor matching
process
Each tyre pressure sensor has a
unique identification code. The
identification code must be matched
to a new wheel position after rotating