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Driving and operating175start moving. Be always prepared
to manually apply the brake to hold the vehicle stationary.
Do not leave the vehicle while it is
being held at a stop by adaptive
cruise control. Always move
selector lever to park position P
and switch off the ignition before
leaving the vehicle.
Setting the following distance
When adaptive cruise control detects
a slower moving vehicle in the driving path, it will adjust the vehicle speed tomaintain the following distance
selected by the driver.
The following distance can be set to
close (1 bar), normal (2 bars) or far
(3 bars).
If the engine is running and the
adaptive cruise control is enabled
(grey), you can modify the following
distance setting:
Press Ö, the current setting is shown
in the Driver Information Centre.
Press Ö again to change the following
distance: The new setting is
displayed in the Driver Information Centre.
The selected following distance is
indicated by full bars in the adaptive
cruise control page.9 Warning
The driver accepts full
responsibility for the appropriate
following distance based on traffic, weather and visibility conditions.
Following distance must be
adjusted or the system switched
off when required by the prevailing
conditions.
Detecting the vehicle ahead
If the system detects a vehicle in the
driving path, the adaptive cruise
control symbol displayed in the Driver
Information Centre changes: - is
changed to w.
Deactivation of the functionality
Press Ñ, the adaptive cruise control
is in pause mode and a message is
displayed. The vehicle is driven
without adaptive cruise control.
The adaptive cruise control is
deactivated, but not disabled. The
last stored set speed remains in
memory for later usage.
The adaptive cruise control is
deactivated automatically when:
● The brake pedal is depressed.
● The vehicle accelerates above 112 mph or slows down below
19 mph.
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176Driving and operating● The electric parking brake isapplied.
● The Traction Control system or Electronic Stability Control is
deactivated or operating.
● The selector lever of automatic transmissions is neither in D nor
in M.
● A fault is detected in the Electronic Stability Control.
Switching off the system
Press C, the adaptive cruise control
mode is disabled and the adaptive
cruise control indication extinguishes
in the Driver Information Centre.
Pressing ß to activate the speed
limiter deactivates adaptive cruise
control.
Switching off the ignition deletes the
stored set speed.
Driver's attention ● Use the adaptive cruise control carefully on bends or mountain
roads, as it can lose the vehicle
ahead and needs time to detect it
again.● Do not use the system on slippery roads as it can create
rapid changes in tyre traction
(wheel spinning), so that you
could lose control of the vehicle.
● Do not use the system when the spare wheel is in use.
System limits9 Warning
The system's automatic brake
force does not permit hard braking and the braking level may not be
sufficient to avoid a collision.
● After a sudden lane change, the system needs a certain time to
detect the next preceding
vehicle. So if a new vehicle is
detected, the system may
accelerate instead of braking.
● The adaptive cruise control does ignore the oncoming traffic.
● The adaptive cruise control does not consider pedestrians and
animals for braking and driving
off.
● The adaptive cruise control considers stopped vehicles only
at low speed.
● Do not use the adaptive cruise control when towing a trailer.
● Do not use the adaptive cruise control on roads with an incline ofmore than 10%.
Bends
The adaptive cruise control calculates
a predicted path based on the
centrifugal force. This predicted path
considers the current bend
characteristic, but cannot consider a
future bend change. The system may lose the current vehicle ahead or
consider a vehicle which is not in the
actual lane. This can happen when
entering or exiting a bend or if the
bend gets stronger or weaker. If it no
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Driving and operating177longer detects any vehicle ahead,
then control indicator A will
extinguish.
If the centrifugal force is too high in a
bend, the system slows down the vehicle slightly. This braking level is
not designed to avoid spinning-off the
bend. The driver is responsible for
reducing the selected speed before
entering a bend and in general to
adapt the speed to the road type and
to existing speed limits.
Motorways
On motorways, adapt the set speed
to the situation and the weather.
Always consider that adaptive cruise
control has a limited visibility range, a
limited braking level and a certain
reaction time to verify if a vehicle is on
the driving path or not. Adaptive
cruise control may not be able to
brake the vehicle in time to avoid a
collision with a much slower vehicle or after a lane change. This is
particularly true while driving fast or if the visibility is reduced due to weather
conditions.
While entering or exiting a motorway,
adaptive cruise control may lose the
vehicle ahead and accelerate up to
the set speed. For this reason,
decrease the set speed before the
exit or before the entry.
Vehicle path changes
If another vehicle enters your driving
path, adaptive cruise control will first
consider the vehicle when it is
completely in your path. Be ready to
take action and depress the brake
pedal, if you need to brake more
quickly.
Hill considerations9 Warning
Do not use the adaptive cruise
control on steep hill roads.
System performance on hills depends
on vehicle speed, vehicle load, traffic
conditions and the road gradient. It
may not detect a vehicle in your path
while driving on hills. On steep hills,
you may have to use the accelerator
pedal to maintain your vehicle speed.
When going downhill you may have to brake to maintain or reduce your
speed.
Note that applying the brake
deactivates the system.
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178Driving and operatingFault
In the event of a fault with the adaptive
cruise control, you are alerted by the
illumination of a warning light and the display of a message in the
instrument panel, accompanied by an
audible signal.
The adaptive cruise control may not
operate correctly if traffic signs do not comply with the Vienna Convention
on Road Signs and Signals.
Have the system checked by a dealer
or a qualified workshop.
As a safety measure, do not use the
system if the brake lights are faulty.
Forward collision alert The forward collision alert may help toavoid or reduce the harm caused by
front-end crashes.
The forward collision alert uses the front camera in the windscreen to
detect a preceding vehicle directly
ahead, in your path.If a vehicle directly ahead is
approached too quickly, a warning
chime and alert in the Driver
Information Centre is provided.9 Warning
Forward collision alert is just a
warning system and does not
apply the brakes. When
approaching a vehicle ahead too
rapidly, it may not provide you
enough time to avoid a collision.
The driver accepts full
responsibility for the appropriate
following distance based on traffic, weather and visibility conditions.
The complete attention of the
driver is always required while
driving. The driver must always be
ready to take action and apply the
brakes.
Activation
Forward collision alert detects
vehicles and operates automatically
at all speeds above 3 mph and
53 mph. The system detects
stationary vehicles if the speed does
not exceed 50 mph.
Alerting the driver
The driver is warned by following
alerts:
● Symbol , illuminates and a
warning message is displayed in the Driver Information Centre
when the distance to the vehicle
ahead gets to small.
● Symbol , illuminates, a warning
message is displayed in the
Driver Information Centre and a
warning chime sounds, when a
collision is imminent and
immediate driver's action is
required.
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Driving and operating1799Warning
Forward collision alert is just a
warning system and does not
apply the brakes. When
approaching a vehicle ahead too
rapidly, it may not provide you
enough time to avoid a collision.
The driver accepts full
responsibility for the appropriate
following distance based on traffic, weather and visibility conditions.
The complete attention of the
driver is always required while
driving. The driver must always be
ready to take action and apply the
brakes.
Caution
The colour lighting of this control
indicator does not correspond to
local traffic laws on following
distance. The driver bears full
responsibility for maintaining safe
following distance according to
applicable traffic rules, weather
and road conditions etc. at all
times.
Selecting the alert sensitivity
The alert sensitivity has to be set to
close, normal or distant in the vehicle personalisation menu 3 116.
The chosen setting will remain until it
is changed. The alert timing will vary
based on vehicle speed. The faster
the vehicle speed, the farther away
the alert will occur. Consider traffic
and weather conditions when
selecting the alert timing.
Deactivation The system can only be deactivated
by deactivating the active emergency
braking in the vehicle personalisation
3 116.
System limitations
Forward collision alert is designed to
warn on vehicles only, but may react
also to other objects.
In the following cases, forward
collision alert may not detect a vehicle ahead or sensor performance is
limited:
● driving on winding or hilly roads
● driving during nighttime
● weather limits visibility, such as fog, rain, or snow
● the sensor in the windscreen is blocked by snow, ice, slush, mud,dirt etc.
● the windscreen is damaged or affected by foreign objects, e.g.
stickers
Active emergency braking
Active emergency braking can help to reduce the damage and injury from
crashes with vehicles, pedestrians
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 or the front pedestrian protection
alert.
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180Driving and operatingForward collision alert 3 178
Front pedestrian protection 3 182
The feature uses various inputs (e.g.
camera sensor, brake pressure,
vehicle speed) to calculate the
probability of a frontal collision.9 Warning
This system is not intended to
replace the driver responsibility for driving the vehicle and looking
ahead. Its function is limited to
supplemental use only to reduce
the vehicle speed before a
collision.
The system may not react to
animals. After a sudden lane
change, the system needs a
certain time to detect the next
preceding vehicle.
The driver must always be ready
to take action and apply the brakes and steer to avoid collisions.
Functionality
Active emergency braking is
equipped with a front camera and
operates in forward gear above
walking speed up to 53 mph. The
system detects stationary vehicles
only if the speed does not exceed
50 mph.
A precondition is that active
emergency braking is not deactivated
in the vehicle personalisation menu
3 116.
If deactivated, m illuminates in the
instrument cluster and a warning
message is displayed in the Driver
Information Centre
If the system has been deactivated
manually, it is reactivated
automatically the next time the
ignition is switched on.
The system includes: ● emergency automatic braking● forward collision alert
● front pedestrian protectionEmergency automatic braking
After activation of brake preparation
system and just before the imminent
collision, this function automatically
applies limited braking to reduce the
impact speed of the collision or
prohibit a crash.
If active emergency braking is
applied, m flashes in the instrument
cluster.
Depending on the situation, the
vehicle may automatically brake
moderately or hard.
Front automatic braking can only
occur if a vehicle or a pedestrian
ahead is detected.
Forward collision alert 3 178
Front pedestrian protection 3 182
Below a speed of 19 mph, emergency automatic braking may slow down thevehicle to a complete stop. If the
speed exceeds 19 mph, emergency automatic braking reduces the speed.
However, the driver must apply the
brake.
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Driving and operating181Emergency automatic braking may
slow the vehicle to a complete stop to
try to avoid a potential crash.
● Automatic transmission: If the vehicle comes to a complete
stop, automatic braking is
maintained for up to two
seconds. Keep the brake pedal
depressed to prevent the vehicle
from starting off again.
● Manual transmission: If the vehicle comes to a complete
stop, the engine may stall.
Operation of the function may be felt
by a slight vibration in the brake
pedal.9 Warning
Emergency automatic braking is
an emergency crash preparation
feature and is not designed to
avoid crashes. Do not rely on the
system to brake the vehicle.
Emergency automatic braking will
not brake outside of its operating speed range and only responds to
detected vehicles and
pedestrians.
System limitations
In some cases, the active emergencybraking system may provide an
automatic braking in situations that
seem to be unnecessary, for instance
in parking garages, due to traffic signs
in a curve or due to vehicles in
another lane. This is normal
operation, the vehicle does not need
service. Firmly apply the accelerator
pedal to override the automatic
braking if the situation and the
surroundings permit.
In the following cases, active
emergency braking performance is
limited:
● Driving on winding or hilly roads.
● Detecting all vehicles, especially vehicles with a trailer, tractors,
muddy vehicles, etc.
● Detecting a vehicle when weather limits visibility, such as infog, rain, or snow.
● Driving during nighttime.
● The windscreen is damaged or affected by foreign items, e.g.
stickers.Complete attention is always required
while driving, and you should be
ready to take action and apply the
brakes and / or steer the vehicle to
avoid crashes.
We recommend to deactivate the system in the vehicle personalisation
in the following cases:
● when towing a trailer or caravan
● when carrying long objects on roof bars or a roof rack
● when the vehicle is being towed with the engine running
● when a spare wheel is fitted that is smaller than the other wheels
● before using an automatic car wash with the engine running
● before placing the vehicle on a rolling road in a workshop
● if the windscreen has been damaged close to the camera
● if the front bumper has been damaged
● if the brake lamps are not working
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182Driving and operatingFault
In case the system requires a service,
m is illuminated in the instrument
cluster, a message is displayed in the Driver Information Centre and an
audible signal is given.
If the system does not work as it
should do, vehicle messages are
displayed in the Driver Information
Centre.
Vehicle messages 3 115.
Front pedestrian protection
Front pedestrian protection may help
to avoid or reduce the harm caused
by front-end crashes with pedestrians when driving forward.
The system uses the front camera in the windscreen to detect a pedestrian
directly ahead in your path.
Front pedestrian protection can
detect and alert to pedestrians in a
forward gear at speeds between
3 mph and 37 mph.
During nighttime driving, system
performance is limited.9 Danger
Front pedestrian braking does not
provide an alert or automatically
brake the vehicle, unless it detects
a pedestrian.
The system may not detect
pedestrians, including children,
when the pedestrian is not directly ahead, not fully visible, not
standing upright, or when part of a
group.
Front pedestrian protection includes:
● detecting front pedestrian ahead● front pedestrian alert
Front pedestrian protection is
activated together with forward
collision alert.
Forward collision alert 3 178.
Detecting front pedestrian ahead
A pedestrian ahead up to a distance
of approximately 40 m is indicated by
a symbol in the instrument cluster.
Front pedestrian alert
When approaching a detected
pedestrian too quickly, a warning
message is displayed in the Driver
Information Centre. A warning chime
is provided.
Cruise control or Adaptive cruise
control may be disengaged when the
front pedestrian alert occurs.
System limitations In the following cases, front
pedestrian protection may not detect
a pedestrian ahead or sensor
performance is limited:
● vehicle speed is out of range from
3 mph to 37 mph in forward gear
● the distance to an pedestrian ahead is more than 40 m
● driving on winding or hilly roads
● driving during nighttime
● weather limits visibility, such as fog, rain, or snow