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218Driving and operatingSystem limitations
Traffic sign assistant may not operate properly when:
● Vehicle speed is faster than 200 km/h.
● Driving on winding or hilly roads. ● During nighttime driving.
● The area of the windscreen, where the front camera is
located, is not clean or affected
by foreign items, e.g. stickers.
● Weather limits visibility, such as fog, rain, or snow.
● The sun is shining directly into the camera lens.
● Traffic signs are completely or partially covered or difficult to
discern.
● Traffic signs are incorrectly mounted or damaged.
● Traffic signs do not comply with the Vienna Convention on Road
Signs and Signals.
● The navigation map data is outdated.Caution
The system is intended to help thedriver 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 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.
Additionally, the status of the lane
keep assist is indicated on the Driver
Assistance page in the Driver
Information Center 3 111.
Unintended lane departure is
assumed
● without using turn lights● using the turn lights in the opposite direction of the lane
departure
● without braking
● without acceleration
● without active steering.
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Driving and operating219Note
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.
Activation
The 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 lights 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.
Indication on Driver Assistance page
If the system is active but one or both
lanes are not detected, they appear
as a line of hollow dashes, as shown
on the right side of the vehicle in the
graphic above.
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220Driving and operatingIf the system detects a lane, it
appears as a green dashed line, as
shown on the right side of the vehicle in the graphic above. This dashed line
becomes amber if the vehicle
approaches a detected lane marking
without the turn lights in that direction
has been used.
If the system intervenes by steering, a short amber line appears, as shown on the left side of the vehicle in the
graphic above.
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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228Driving and operatingrelease handle is impossible toguide 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
3 175.
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236Vehicle careReplacing the vehicle batteryNote
Any deviation from the instructions
given in this section may lead to
temporary deactivation or
disturbance of the stop-start system.
When the vehicle battery is being
replaced, please ensure that there
are no open ventilation holes in the
vicinity of the positive terminal. If a
ventilation hole is open in this area, it
must be closed off with a dummy cap, and the ventilation in the vicinity of the negative terminal must be opened.
Ensure that the battery is always
replaced by the same type of battery.
We recommend that you have the
vehicle battery replaced by a
workshop.
Stop-start system 3 157.Charging the vehicle battery9 Warning
On vehicles with stop-start
system, ensure that the charging potential does not exceed 14.6 V
when using a battery charger.
Otherwise the vehicle battery may be damaged.
Jump starting 3 269.
Discharge protection Battery voltage
When the vehicle battery voltage is
running low, a warning message will
appear in the Driver Information
Centre.
1. Switch off any electrical consumers which are not requiredfor a safe ride, e.g. seat heating,
heated rear window or other main consumers.
2. Charge the vehicle battery by driving continuously for a while or
by using a charging device.
The warning message will disappear
after the engine has been started
twice without a voltage drop.
If the vehicle battery cannot be
recharged, have the cause of the fault
remedied by a workshop.
Vehicle battery state of charge
function
The function guarantees longest vehicle battery life via a generator
with controllable power output and
optimised power distribution.
To prevent discharge of the vehicle
battery when driving, the following
systems are reduced automatically in two stages and finally switched off:
● auxiliary heater
● heated rear and front window
● heated steering wheel
● heated mirrors
● heated seats
● fan
In the second stage, a message
which confirms the activation of the
vehicle battery discharge protection
will be displayed in the Driver
Information Centre.
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250Vehicle careNo.Circuit1–2–3ABS4–5–6Tailgate7Rear fog light / Front fog lights8Memory 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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252Vehicle 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 sensor13AdBlue module14Heated steering wheel15Transmission control module16Amplifier17Alarm
Page 255 of 315
Vehicle care253No.Circuit18Body control module19AdBlue 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 wiper38Emergency call39Display40Parking assist41Overhead console42Infotainment SystemVehicle 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 3 265.