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Driving and operating211Traffic sign assistant
Functionality
Traffic sign assistant detects
designated traffic signs via a front
camera and displays them in the
Driver Information Centre.
If the vehicle is equipped with an
embedded navigation system, traffic signs from data maps may be
included additionally.
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
● time constraints
● distance constraints
● direction arrows
Speed limit signs and no passing
signs are displayed in the Driver
Information Centre until the nextspeed limit sign or end of speed limit
is detected or up to a defined sign
timeout.
Indication of multiple signs on the
display is possible.
An exclamation mark in a frame
indicates that there is an additional
sign detected which cannot be clearly
identified by the system.
The system operates without loss of
performance up to a speed of
200 km/h depending on the lighting
conditions. At night the system is
active up to a speed of 160 km/h.
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216Driving and operatingThe system is operational at vehicle
speeds between 60 km/h and
180 km/h and if lane markings are
available.
The system gently turns the steering
wheel and the control indicator a
changes to yellow, if the vehicle
approaches a detected lane marking
without using the turn signal in that
direction.
The system alerts by flashing a
together with three chimes, from the
respective direction, if the lane is
departed significantly.
The system is only operable when a
lane marking is detected.
If the system only detects lane
markings on one side of the road, it
will only assist for this side.
Lane keep assist detects hands-free
driving. In this case a message in the
Driver Information Centre pops-up
and a chime sounds as long as lane
keep assist detects hands-free
driving.Deactivation
The system is deactivated by
pressing a; the LED in the button
extinguishes.
Fault
The system performance may be
affected by:
● Windscreen not clean or affected
by foreign items, e.g. stickers
● Close vehicles ahead
● Banked roads
● Winding or hilly roads
● Road edges
● Roads with poor lane markings
● Sudden lighting changes
● Adverse environmental conditions e.g. heavy rain or
snow
● Vehicle modifications, e.g. tyres.
Switch off the system if the system is
disturbed by tar marks, shadows, road cracks, temporary or
construction lane markings, or other
road imperfections.9 Warning
Always keep your attention on the
road and maintain proper vehicle
position within the lane, otherwise
vehicle damage, injury or death
could occur.
Lane keep assist does not
continuously steer the vehicle.
The system may not keep the
vehicle in the lane or give an alert,
even if a lane marking is detected.
The steering of the lane keep
assist may not be sufficient to
avoid a lane departure.
The system may not detect hands-
off driving due to external
influences (road condition and
surface, weather etc). The driver
has full responsibility to control the vehicle and is always required tokeep the hands on the steeringwheel while driving.
Using the system while towing a
trailer or on slippery roads could
cause loss of control of the vehicle
and a crash. Switch the system off.
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Driving and operating221For the values specific to your
vehicle, refer to the EEC Certificate of
Conformity provided with your vehicle
or other national registration
documents.
General information The official fuel consumption and
specific CO 2 emission figures quoted
relate to the EU base model with
standard equipment.
Fuel consumption data and CO 2
emission data are determined
according to regulation R (EC)
No. 715/2007 (in the latest applicable
version), taking into consideration the
vehicle weight in running order, as specified by the regulation.
The figures are provided only for the
purpose of comparison between different vehicle variants and mustnot be taken as a guarantee for the
actual fuel consumption of a
particular vehicle. Additional
equipment may result in slightly
higher results than the stated
consumption and CO 2 figures.Furthermore, fuel consumption is
dependent on personal driving styleas well as road and traffic conditions.Trailer hitch
General information
Only use towing equipment that has
been approved for your vehicle.
Entrust retrofitting of towing
equipment to a workshop. It may be
necessary to make changes that
affect the cooling system, heat
shields or other equipment.
The bulb outage detection function for trailer brake light cannot detect a
partial bulb outage, e.g. in case of four
times five watt bulbs, the function only detects lamp outage when only a
single five Watt lamp remains or none remain.
Fitting of towing equipment could
cover the opening of the towing eye.
If this is the case use the coupling ball
bar for towing. Always keep the
coupling ball bar in the vehicle when
not in use.
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222Driving and operatingDriving characteristics andtowing tips
Before attaching a trailer, lubricate the coupling ball. However, do not do
so if a stabiliser, which acts on the coupling ball, is being used to reduce snaking movements.
During trailer towing do not exceed a
speed of 80 km/h. A maximum speed
of 100 km/h is only appropriate if an
oscillation damper is used and the
permissible gross trailer weight does
not exceed the vehicle’s curb weight.
For trailers with low driving stability
and caravan trailers, the use of an
oscillation damper is strongly
recommended.
If the trailer starts snaking, drive more slowly, do not attempt to correct the
steering and brake sharply if
necessary.
When driving downhill, drive in the
same gear as if driving uphill and
drive at a similar speed.
Adjust tyre pressure to the value
specified for full load 3 293.Trailer towing
Trailer loads The permissible trailer loads are
vehicle and engine-dependent
maximum values which must not be
exceeded. The actual trailer load is
the difference between the actual
gross weight of the trailer and the
actual coupling socket load with the
trailer coupled.
The permissible trailer loads are
specified in the vehicle documents. In general, they are valid for gradients
up to 12%.
The permissible trailer load applies
up to the specified incline and at sea
level. Since engine power decreases
as altitude increases due to the air
becoming thinner, therefore reducing
climbing ability, the permissible gross
train weight also decreases by 10%
for every 1000 metres of altitude. The gross train weight does not have to be
reduced when driving on roads with
slight inclines (less than 8%, e.g.
motorways).The permissible gross train weight must not be exceeded. This weight is specified on the identification plate
3 280.
Vertical coupling load
The vertical coupling load is the load
exerted by the trailer on the coupling
ball. It can be varied by changing the
weight distribution when loading the
trailer.
The maximum permissible vertical
coupling load (75 kg) is specified on
the towing equipment identification
plate and in the vehicle documents.
Always aim for the maximum load,
especially in the case of heavy
trailers. The vertical coupling load
should never fall below 25 kg.
Rear axle load
When the trailer is coupled and the
towing vehicle fully loaded, the
permissible rear axle load (see
identification plate or vehicle
documents) may be exceeded by
40 kg. If the permissible rear axle load is exceeded, a maximum speed of100 km/h applies.
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Driving and operating223Towing equipmentCaution
When operating without a trailer,
remove the coupling ball bar.
Stowage of coupling ball bar
The bag with the coupling ball bar is
stowed on the rear floor cover in the
load compartment.
Place the strap through the rear right
lashing eye, wrap around twice and
tighten the strap to secure the bag.
Illustration shows 5-door hatchback.
Illustration shows Sports Tourer.
Fitting the coupling ball bar
On Sports Tourer remove cover from
rear bumper by pushing.
Disengage and fold down the
connecting socket. Remove the
sealing plug from the opening for the
coupling ball bar and stow it.
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224Driving and operatingChecking the tensioning of the
coupling ball bar
● Red marking on rotary knob must
point towards green marking on
coupling ball bar.
● The gap between the rotary knob
and the coupling ball bar must be approx. 6 mm.
● The key must be in position c.
Otherwise, the coupling ball bar must be tensioned before being inserted:
● Unlock coupling ball bar by turning key to position c.
● Pull out rotary knob and turn
clockwise as far as it will go.
Inserting the coupling ball bar
Insert the tensioned coupling ball bar
in the opening and push firmly
upwards until it audibly engages.
The rotary handle snaps back into its
original position resting against the
coupling ball bar without a gap.9 Warning
Do not touch rotary handle during
insertion.
Lock the coupling ball bar by turning
the key to position e. Remove the key
and close the protective flap.
Eye for break-away stopping cable
Page 227 of 311
Driving and operating225Attach breakaway stopping cable to
eye.
Check that the coupling ball bar is
correctly installed
● Green marking on rotary knob must point towards green
marking on coupling ball bar.
● There must be no gap between the rotary handle and the
coupling ball bar.
● The coupling ball bar must be firmly engaged in the opening.
● The coupling ball bar must be locked and the key removed.9Warning
Towing a trailer is permitted only
when a coupling ball bar is fitted correctly. If the coupling ball bardoes not engage correctly, seekthe assistance of a workshop.
Dismounting the coupling ball bar
Open the protective flap and turn the
key to position c to unlock the
coupling ball bar.
Pull out rotary handle and turn
clockwise as far as it will go. Pull out coupling ball bar downwards.
Insert sealing plug in opening.
Fold away connecting socket.
On Sports Tourer insert cover into
rear bumper as shown in the
illustration.
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226Driving and operatingStow the coupling ball bar in the bag
and secure by fixing the strap through the rear right lashing eye. Wrap
around twice and tighten the strap to
secure the bag.
Trailer stability assist
If the system detects snaking
movements, engine power is reduced
and the vehicle/trailer combination is selectively braked until the snaking
ceases. While system is working keep
steering wheel as still as possible.
Trailer stability assist is a function of
the Electronic Stability Control 3 180.