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Driving and operating229The driver assistance systems donot relieve the driver from full
responsibility for vehicle
operation.
Lane keep assist
Lane keep assist helps to avoid
crashes due to unintentional lane
departures. The front camera
observes the lane markings between
which the vehicle is driving. If the
vehicle approaches a lane marking, the steering wheel is gently turned to
position the vehicle back into the lane. Turn steering wheel in same
direction, if system steering is not
sufficient. Turn steering wheel gently
into opposite direction, if lane change
is intended.
When crossing a lane marking
significantly, lane keep assist starts a
visual and acoustic warning.
Unintended lane departure is
assumed
● without using turn signal
● using the turn signal in the opposite direction of the lane
departure
● without braking
● without acceleration
● without active steering.
Note
The system is switched off during
detection of ambiguous lane
markings, e.g. in construction areas.
Note
The system may be switched off if it
detects lanes which are too narrow,
too wide or too curved.
ActivationThe lane keep assist is activated by
pressing a. The LED in the button
illuminates to indicate that the system
is switched on.
When the control indicator a in the
instrument cluster or in the head-up display illuminates green, the system
is ready to assist.
The 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.
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230Driving and operatingThe 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.
The system is deactivated
automatically when a trailer is
detected.
System limitations
The system performance may not
operate properly when:
● Vehicle speed is out of range from 60 to 180 km/h.
● Driving on winding or hilly roads.
● During nighttime driving.● Weather limits visibility, such as fog, rain, or snow.
● The sensor in the windscreen is blocked by snow, ice, slush, mud,dirt, windscreen damage or
affected by foreign items, e.g.
stickers.
● The sun is shining directly into the camera lens.
● Close vehicles ahead
● Banked roads
● Road edges
● Roads with poor lane markings
● Sudden lighting changes
● 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 operating235Driving characteristics and
towing 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 kerb 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 3 301.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
3 288.
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 of 60 kg
(engines B20DTH / B20NFT: 90 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.
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Driving and operating237Stow/hide coupling ball bar
Pull the grip located left of the number
plate under the rear bumper fascia at an angle of approx. 45° to the ground.
A buzzing tone sounds as a warning
when the release handle is pulled out and the ball neck is disengaged.
With the flat of the hand, swivel the
released coupling ball bar to the right
until it engages under the floor. Make sure that the release handle is back inits hidden initial position, otherwise
the buzzing tone will not stop.
9 Warning
Towing a trailer is permitted only
when the coupling ball bar is fitted correctly. If the coupling ball bar
does not engage correctly or if the
release handle is impossible to guide to its hidden initial position in the housing or if the buzzing tone
sounds after engaging the
coupling ball bar, seek the
assistance of a workshop.
Eye for break-away stopping cable
Attach break-away stopping cable to
eye.
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 the system is working
keep steering wheel as still as
possible.
Trailer stability assistant is a function
of the Electronic Stability Control
3 183.
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258Vehicle careNo.Circuit1–2–3ABS4–5–6Tailgate7Fog light8Memory module9Heated windscreen10Seat lumbar11DC/DC battery12Heated rear window13Heated mirror14–15–16Front wiper17Power seat, passengerNo.Circuit18Sunblind19Power seat, driver20–21Sunroof22Rear wiper/Airbag23Adaptive forward lighting24–25–26Transmission control module27Ignition/Instrument panel28–29Rear view camera/Air vent30Malfunction indicator light/
Trailer31–32Camera33Seat heat front34Seat heat rearNo.Circuit35Damping/All-wheel drive36Fuel system37–38–39–40Steering wheel lock41–42–43Heated steering wheel44Headlight range adjustment45–46Engine control module47–48DC/DC converter/Air vent/E-
Boost49Rear door control module50–51–
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260Vehicle careInstrument panel fuse box
In left-hand drive vehicles, the fuse
box is behind a cover in the
instrument panel.
Disengage cover at the side and
remove.
In right-hand drive vehicles, the fuse
box is located behind a cover in the
glovebox. Open the glovebox and
remove the cover.
No.Circuit1Left power window2Right power window3Body control module4Climate control fan5Body control module6Trailer provisions7Rear seat power folding8Body control module9Engine control module10Head-up display11NO x reduction/Pipe heater12NO
x reduction/Soot sensor13UREA module14Heated steering wheel15Transmission control module16Amplifier17Alarm
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Vehicle care261No.Circuit18Body control module19UREA module20Body control module21Body control module22Body control module23Electric steering wheel lock24Airbag25Diagnostic connector26Power outlet load compartment27EBCM valve28Police provision29–30–31Steering wheel controls32Ignition switch33Climate control34Central gateway moduleNo.Circuit35AUX/USB connector36Wireless charger37Rear wiper38Onstar39Display40Parking assist41Overhead console42RadioVehicle tools
Tools
Vehicles with spare wheel
The jack with wheel wrench, the tools,
an extension bolt for securing a
damaged wheel and the towing eye
are placed in the tool box below the
spare wheel in the load compartment. Spare wheel 3 275.
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268Vehicle careAlways use fine mesh chains that addno more than 10 mm to the tyre tread
and the inboard sides (including chain
lock).9 Warning
Damage may lead to tyre blowout.
Tyre chains are only permitted on
tyres of size 215/60 R16, 215/55 R17 ,
225/55 R17 and 235/45 R18.
Temporary spare wheel
The use of tyre chains is not permitted on the temporary spare wheel.
Tyre repair kit
Minor damage to the tyre tread can be
repaired with the tyre repair kit.
Do not remove foreign bodies from
the tyres.
Tyre damage exceeding 4 mm or that is at tyre's side wall cannot be
repaired with the tyre repair kit.
9 Warning
Do not drive faster than 80 km/h.
Do not use for a lengthy period.
Steering and handling may be
affected.
Two types of tyre repair kit are
available:
● Type 1 indicated by the on/off
switch at the top of the
compressor.
● Type 2 indicated by the on/off
switch at the side of the
compressor.
If vehicle has a flat tyre:
Apply the parking brake and engage first gear, reverse gear or P.