128Driving and operatingThe adaptive cruise control is
deactivated automatically in the
following cases:
● The brake pedal is depressed.
● The vehicle accelerates above 112 mph (manual and automatic
transmission) or slows down
below 19 mph (manual
transmission).
● The electric parking brake is applied.
● 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 or the
radar system.
● Immediately after the clutch pedal has been depressed or afew seconds after the clutch
pedal has been depressed
(depending on the manual
transmission).Switching off the system
Press w, the adaptive cruise control
mode is disabled and the adaptive
cruise control indication extinguishes
in the Driver Information Centre.
Pressing 5 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 mountainroads, 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 adaptive cruise control during rain, snow or
heavy dirt, as the radar sensor
can be covered by a water film,
dust, ice or snow. This reduces or
suppresses completely thevisibility. In case of sensor
blockage, clean the sensor
cover.
● 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.
130Driving and operatingIf 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.
Radar unit
The radar unit is located in the middle of the front bumper.
9 Warning
The radar unit was aligned
carefully during manufacture.
Therefore, in the event of a front-
end impact, do not use the system.
The front bumper may appear to
be intact, however the sensor
behind may be affected and react
incorrectly. After an accident,
consult a workshop to verify and
adjust the radar unit position.9 Warning
The usage of a license plate
support may have an impact on
the proper operation of the radar
unit and may limit sensor
perfomance. Vehicles driving
ahead, pedestrians or other
objects located in front of the
vehicle may not be detected by the
system.
Do not use a license plate support on the front bumper to ensure
proper system functionality.
Fault
In the event of a fault with the adaptive cruise control, you are alerted by the
illumination of a warning light and the
Driving and operating131display 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.
Do not use the system if the front
bumper is damaged.
Active emergency braking
Active emergency braking can help to reduce the damage and injury from
crashes with vehicles and
pedestrians directly ahead, when the driver does not actively take action
either by manual braking or by
steering. Before the active
emergency braking applies, the driver
is warned by the forward collision
alert.
Forward collision alert 3 134
Front pedestrian protection 3 136Active emergency braking can be
deactivated in the vehicle
personalisation 3 76. If deactivated,
m illuminates in the instrument
cluster and a warning message is
displayed in the Driver Information Centre. When ignition is switched onnext time, system is activated.
The feature uses various inputs (e.g.
camera sensor, radar 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.9 Warning
The usage of a license plate
support may have an impact on
the proper operation of the radar
unit and may limit sensor
perfomance. Vehicles or
pedestrians driving or walking
ahead may not be detected by the
system.
Do not use a a license plate
support to ensure proper system
functionality.
Functionality
Depending on the vehicle
configuration and the detected
objects, there are several operational speed ranges.
On vehicles equipped only with front
camera, the active emergency
braking operates from 3 mph to 50 mph when a vehicle has been
detected.
132Driving and operatingOn vehicles equipped with radar
sensor and front camera, the active
emergency braking operates from
3 mph to 87 mph when a vehicle has
been detected.
Active emergency braking only works when the seat belts of the front
passengers are fastened.
The system includes: ● brake preparation system
● emergency automatic braking ● smart brake assist
● forward collision alert
● front pedestrian protection
Brake preparation system
When approaching a vehicle ahead
or a pedestrian so quickly that a
collision is likely, the brake
preparation system slightly
pressurises the brakes. This reduces
the response time, when braking is
requested.Emergency 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.
Emergency automatic braking can
only occur if a vehicle or a pedestrian
ahead is detected.
Forward collision alert 3 134
Front pedestrian protection 3 136
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.
Emergency 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.
Driving and operating133Smart brake assist
Smart brake assist provides a boost
to braking when the brake pedal is quickly applied. The braking is based on the speed of approach and
distance to a vehicle ahead.
Minor brake pedal pulsations or pedal movement during this time is normal
and the brake pedal should continue to be applied as needed. Intelligent
brake assist will automatically
disengage only when the brake pedal is released.9 Warning
Smart brake assist may increase
vehicle braking in situations when
it may not be necessary. You
could block the flow of traffic. If this occurs, take your foot off the brakepedal and then apply the brakes
as needed.
Forward collision alert 3 134.
Front pedestrian protection 3 136.
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 various
types of objects, i.e., traffic signs or
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
might be limited:
● driving on winding or hilly roads
● detecting vehicles with a trailer, tractors, muddy vehicles, etc.
● detecting a vehicle when weather
limits visibility, such as in fog,
rain, or snow
● driving during nighttime● the sensor in the windscreen or the radar unit behind the front
bumper are blocked by snow, ice,
slush, mud, dirt etc.
● the windscreen is damaged or affected by foreign objects, e.g.
stickers
the bumper is damaged or
affected by foreign objects, e.g.
license plate support
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 the vehicle is fitted with snow chains
● when a spare wheel is fitted that is smaller than the other wheels
134Driving and operating● before using an automatic carwash 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 lights are not working
Fault
In case the system requires a service, a message is displayed in the Driver
Information Centre.
If the system does not work properly,
vehicle messages are displayed in
the Driver Information Centre.
Vehicle messages 3 75.
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 and
depending on the vehicle
configuration a radar unit located
behind the front bumper to detect a
vehicle directly ahead, in the path.
If a vehicle directly ahead is
approached too quickly, a warning
chime sounds and a message is
displayed in the Driver Information Centre.
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.
9 Warning
The usage of a license plate
support may have an impact on
the proper operation of the radar
unit and may limit sensor
perfomance. Vehicles driving
ahead, pedestrians or other
Driving and operating135objects located in front of the
vehicle may not be detected by the
system.
Do not use a license plate support on the front bumper to ensure
proper system functionality.
Activation
Depending on the vehicle
configuration and the detected
objects, there are several operational
speed ranges.
On vehicles equipped only with front camera, the forward collision alert
operates from 3 mph to 50 mph when
a vehicle has been detected.
On vehicles equipped with radar
sensor and front camera, the forward
collision alert operates from 3 mph to
87 mph when a vehicle has been
detected.
Alerting the driver
The driver is warned by following
alerts:
● Symbol , and a warning
message are displayed in the
Driver Information Center, when
the distance to the vehicle ahead
gets to small.
● Symbol , and a warning
message are displayed in the
Driver Information Center and a
warning chime sounds, when a
collision is imminent and
immediate driver's action is
required.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.9 Warning
The usage of a license plate
support may have an impact on
the proper operation of the radar
unit and may limit sensor
perfomance. Vehicles or
pedestrians driving or walking
ahead may not be detected by the
system.
Do not use a a license plate
support to ensure proper system
functionality.
Selecting the alert sensitivity
Three alert sensivities can be
selected in the settings of the active
emergency braking within the vehicle personalisation 3 76.
The chosen setting will be memorised
when the ignition has been switched
off. The alert timing will vary based on
136Driving and operatingselected alert setting and vehicle
speed. 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 76. When ignition is switched on
next time, system is activated.
System limitations
Forward collision alert is designed to
warn on vehicles, 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 orthe radar unit behind the front
bumper are blocked by snow, ice,
slush, mud, dirt etc.
● the windscreen is damaged or affected by foreign objects, e.g.
stickers
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 and depending on the vehicle configuration a radar unit inthe front bumper to detect a
pedestrian directly ahead in the path.9 Warning
The usage of a license plate
support may have an impact on
the proper operation of the radar
unit and may limit sensor
perfomance. Vehicles or
pedestrians driving or walking
ahead may not be detected by the
system.
Do not use a a license plate
support to ensure proper system
functionality.
Front pedestrian protection can
detect and alert to pedestrians in a
forward gear at speeds between
3 mph and 37 mph. Additionally, front pedestrian protection can provide a
boost to braking or automatically
brake the vehicle.
During nighttime driving, system
performance is limited.