Page 218 of 311

216Driving and operatingSwitch 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 to keep 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.Fuel
Fuel for petrol engines
Only use unleaded fuel that complies
with European standard EN 228 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.
Page 223 of 311

Driving and operating221The refuelling procedure must becompleted, i.e. the filler neck must be
vented.
The capacity of the natural gas tank
depends on outside temperature,
filling pressure, gas composition and
type of refuelling system.
Capacities 3 289.
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)
Fuel filler cap
Only use genuine fuel filler caps.
Diesel-engined vehicles have special fuel filler caps.
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 bulbs with a power of 5 W each,
the function only detects light outage
when only a single 5 W bulb 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.
Page 224 of 311

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 3 290.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 m 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
3 281.
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 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 of
100 km/h applies.
Page 225 of 311
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.
Page 227 of 311

Driving and operating225Illustration shows 5-door hatchback.
Illustration shows Sports Tourer.
Attach 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.
Page 228 of 311
226Driving and operating
Stow 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 3 179.
Page 250 of 311

248Vehicle careNo.Circuit32DC transformer / LED display /
Electrical heater / Climate
control / Glow plug controller33Anti theft warning horn34Horn35Power outlet load compartment36Right high beam (Halogen) /
Right low beam (LED)37Left high beam (Halogen)38LED headlight / Automatic
headlight range adjustment39Front fog light40Central Gateway Module41Water in fuel sensor / Water
pump42Manual headlight range adjust‐
ment43Fuel pump44Rear view camera / Inside rear
view mirror / Trailer moduleNo.Circuit45LED headlight left / Automatic
headlight range adjustment left46Instrument cluster47Steering column lock48Rear wiper49Outside rearview mirror50LED headlight right / Automatic
headlight range adjustment
right51Left low beam (LED)52Engine control module / Trans‐
mission control module53Diesel exhaust system54Windscreen wiper55Electrical rear seat folding56–57–
After having changed defective fuses,
close the fuse box cover and press
until it engages.
If the fuse box cover is not closed
correctly, malfunction may occur.
Instrument panel fuse boxThe fuse box is located behind a
cover.
Pull the cover on the left side to
remove.
Page 253 of 311
Vehicle care251No.Circuit1–2–3Trailer module4–5–6–7–8–9–10Service11–12Front seat heating (on vehicles
with alarm horn)13Rear seat heating (on vehicles
with alarm horn)14Ignition15Seat ventilation16Trailer outletNo.Circuit17Trailer outlet18–19–20–21–22–
After having changed defective fuses,
close the fuse box cover and press
until it engages.
Additional fuses are located near the
vehicle battery.