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168Driving and operating
Fault9Warning
If there is a fault in the ABS, the
wheels may be liable to lock due
to braking that is heavier than
normal. The advantages of ABS are no longer available. During
hard braking, the vehicle can no longer be steered and may
swerve.
Have the cause of the fault remedied
by a workshop.
Parking brake
Manual parking brake9 Warning
Always apply parking brake firmly
without operating the release
button, and apply as firmly as
possible on a downhill or uphill
slope.
To release the parking brake, pull
the lever up slightly, press the
release button and fully lower the
lever.
To reduce the operating forces of
the parking brake, depress the
foot brake at the same time.
Control indicator R 3 109.
Electric parking brake
Applying when vehicle is stationary
9 Warning
Pull switch m for approx.
one second, the electric parking
brake operates automatically with
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184Driving and operating
Press button E; the current setting is
shown in the Driver Information
Centre. Press button E again to
change the alert sensitivity. The
setting is also displayed in the top line
of the Driver Information Centre.Note that the alert timing sensitivity
setting is shared with the following distance setting of the adaptive cruise control. So changing the alert timing
sensitivity changes the adaptive
cruise control following distance
setting.
Alerting the driver
A green illuminated vehicle ahead
control indicator A lights up in the
instrument cluster when the system has detected a vehicle in the driving
path. When the distance to a
preceding moving vehicle gets too
small or when approaching another
vehicle too rapidly and a collision is
imminent, the collision alert symbol
pops up in the Driver Information
Centre. Simultaneously a warning
chime sounds.
Depress the brake pedal, if it is
required by the situation.
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Driving and operating185
SettingsSettings can be changed in the Auto
collision preparation menu in the
vehicle personalisation 3 126.
Forward collision alert based on front camera system
Forward collision alert uses the front
camera system in the windscreen to
detect a vehicle directly ahead, in
your path, within a distance of approx. 60 metres.
Activation
Forward collision alert operates
automatically above 25 mph, if it is not
deactivated by button V, see below.
Selecting the alert sensitivity
The alert sensitivity can be set to
near, medium or far.
Press button V; the current setting is
shown in the Driver Information
Centre. Press button V again to
change the alert sensitivity.
Alerting the driver
A green illuminated vehicle ahead
control indicator A lights up in the
instrument cluster when the system has detected a vehicle in the driving
path.
When the distance to a preceding
moving vehicle gets too small or when
approaching another vehicle too
rapidly and a collision is imminent, the
collision alert symbol pops up in the
Driver Information Centre.
Simultaneously a warning chime
sounds. Depress the brake pedal, if it is required by the situation.
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Driving and operating187
The minimum indicated distance is
0.5 s.
If there is no vehicle ahead or the vehicle ahead is out of range, two
dashes will be displayed: -.- s.
Active Emergency Braking
Active emergency braking can help to reduce the damage from crashes with vehicles and obstacles directly
ahead, when a collision can no longer be avoided either by manual braking
or by steering. Before the active
emergency braking applies, the driver
is warned by the forward collision
alert 3 183.
The feature uses various inputs (e.g.
radar sensor, brake pressure, vehicle speed) to calculate the probability of
a frontal collision.
Active emergency braking operates automatically above walking speed,
provided that Auto collision
preparation setting is not deactivated
in the vehicle personalisation menu
3 126.
The system includes: ■ Brake preparation system
■ Emergency automatic braking
■ Forward looking brake assist9 Warning
This system is not intended to
replace the driver responsibility of driving the vehicle and looking
ahead. Its function is limited to
supplemental use only. The driver
shall continue to apply the brake
pedal as the driving situation
dictates.
Brake preparation system
When approaching a vehicle ahead
so quickly that a collision is likely, the brake preparation system slightly
pressurises 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
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196Driving and operating
When the system detects a vehicle inthe side blind zone while driving
forward, either while passing a
vehicle or being passed, an amber
warning symbol B will illuminate in
the relevant exterior mirror. If the
driver then activates the turn signal,
the warning symbol B starts flashing
amber as a warning not to change
lanes.
Notice
If the passing vehicle is at least 6
mph faster than the passed vehicle,
the warning symbol B in the relevant
exterior mirror will not illuminate.Side blind spot alert is active from
speeds of 6 mph up to 87 mph.
Driving faster than 87 mph
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
come on to indicate that the system is operating.
The system can be activated or
deactivated in the menu Settings in
the Info-Display, vehicle
personalisation 3 126.
Deactivation is indicated by a
message in the Driver Information
Centre (DIC).
Detection zones
The system sensor covers a zone of
approx. 3 metres on both sides of the
vehicle. This zone starts at each
exterior mirror and extends rearwardsby approx. 3 metres. The height of the zone is approx. between 0.5 metres
and 2 metres off the ground.
The system is deactivated if the
vehicle is towing a trailer.
Side blind spot alert is designed to
ignore stationary objects such as
guardrails, posts, curbs, walls and
beams. Parked vehicles or oncoming
vehicles are not detected.
Fault
Occasional missed alerts can occur
under normal circumstances and will
increase in wet conditions.
Side blind spot alert does not operate when the left or right corners of the
rear bumper are covered with mud,
dirt, snow, ice, slush, or in heavy
rainstorms. Cleaning instructions
3 260.
In the event of a fault in the system or if the system does not work due to
temporary conditions, a message is
displayed in the Driver Information
Centre (DIC). Seek the assistance of
a workshop in case of a permanent
fault.
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198Driving and operating
Trajectory lane of the vehicle is
shown in accordance with the
steering angle.
The function can be deactivated in the
Settings menu in the Info-Display.
Vehicle personalisation 3 126.
Warning symbols
Warning symbols are indicated as
triangles 9 on the picture which
shows obstacles detected by the rear sensors of the advanced parking
assist.
Display settings
Brightness can be set with the up/
down buttons of the multifunction
knob.
Contrast can be set with left/right
buttons of the multifunction knob.
Deactivation
The camera is deactivated when a
certain forward speed is exceeded or if reverse gear is not engaged for
approx. 10 seconds.
Activation or deactivation of the rear
view camera can be changed in the Settings menu in the Info-Display.
Vehicle personalisation 3 126.
Fault
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.
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Driving and operating199
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:
■ motorways
■ A-roads
■ play streetsAdd on signs ■ additional hints to traffic signs
■ restriction of trailer towing
■ 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.
Combinations of more signs in the
display are possible.
An exclamation mark in a frame
indicates that there is an additional
sign detected which cannot be
recognised by the system.
The system is active up to a speed of
124 mph depending on the lighting
conditions. At night the system is
active up to a speed of 99 mph.
As soon as the speed becomes
slower than 34 mph the display will be reset and the content of the traffic sign
page will be cleared, e.g. when
entering a city zone. The next
recognized speed indication will be
displayed.
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Driving and operating201
Once setting page is displayed, selectOff to deactivate pop-up function.
Reactivated by selecting On. When
switching on the ignition, pop-up function is deactivated.
Pop-up indication is displayed for approx. 8 seconds in the Driver
Information Centre.
Fault
The traffic sign assistant system may
not operate correctly when:
■ the area of the windscreen, where the front camera is located, is notclean
■ 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. In this
case No Traffic Sign Detection due
to Weather is indicated on the
display
■ 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 systemobserves 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.