190Driving and operating
If Adaptive cruise control is active,
this page shows the alert sensitivity
setting instead of following distance setting 3 179.
Active emergency braking Active emergency braking can help toreduce the damage and injury 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 3 187.
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 for
animals. After a sudden lane
change, the system needs a
certain time to detect the next
preceding vehicle.
The driver shall always be ready to take action and apply the brakes
and steer to avoid collisions.
Functionality
If equipped only with front camera the active emergency braking operates in
forward gear above walking speed up to 80 km/h.
With radar sensor active emergency
braking operates in forward gear
above walking speed at all speeds.
Number plate mounting 3 222.
A precondition is that forward collision
alert is not deactivated in the vehicle
personalisation menu 3 124.
The system includes: ● brake preparation system
● emergency automatic braking
● forward looking brake assist
● intelligent brake assist (only with radar sensor)
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.
If equipped only with front camera the
system operates up to a speed of
80 km/h.
Driving and operating191Emergency automatic brakingAfter 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. Depending on the
situation, the vehicle may
automatically brake moderately or
hard. This front automatic braking can
only occur if a vehicle ahead is
detected, indicated by the vehicle
ahead indicator A 3 187.
If equipped only with front camera the
system operates up to a speed of
80 km/h.
Below a speed of 40 km/h the system can apply full braking.
Emergency automatic braking may
slow the vehicle to a complete stop to
try to avoid a potential crash. If this
happens, emergency automatic
braking may engage the electric
parking brake to hold the vehicle at a
stop. To release press the electric
parking brake button or firmly press
the accelerator 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.
Forward looking brake assist
In addition to the brake preparation
system and emergency automatic
braking, the forward looking brake
assist function makes the brake assist more sensitive. Therefore, pressing
the brake pedal less strongly results
in immediate hard braking. This
function helps the driver brake
quicker and harder before the
imminent collision.
If equipped only with front camera the
system operates up to a speed of
85 km/h.
9 Warning
Active emergency braking is not
designed to apply hard
autonomous braking or to
automatically avoid a collision. It is designed to reduce the vehicle
speed before a collision. It may not
react for pedestrians or animals.
After a sudden lane change, the
system needs a certain time to
detect the next preceding vehicle.
The complete attention of the
driver is always required while
driving. The driver shall always be ready to take action and apply the
brakes and steer to avoid
collisions. The system is designed to work with all occupants wearingtheir seat belts.
Intelligent Brake Assist
If the vehicle is equipped with radar
sensor Intelligent brake assist may
activate when the brake pedal is
applied quickly by providing a boost
to braking based on the speed of
approach and distance to a vehicle
ahead.
192Driving and operatingMinor brake pedal pulsations or pedalmovement 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
Intelligent 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 brake pedal and
then apply the brakes as needed.
Deactivation
On vehicles with front camera active
emergency braking can be
deactivated by repeatedly pressing
the gap switch V to Off setting,
3 187. If deactivated a message is
displayed in the Driver Information
Centre.
On vehicles with radar sensor the
system can be disabled in the
personalisation menu in the Info
Display 3 124.
We recommend to deactivate the
system or set it to alert only in the
following cases:
● when the vehicle is being towed
● if a trailer is attached to the vehicle
● before using an automatic car wash with ignition switched on
● if the windscreen has been damaged close to the camera
● if the front bumper has been damaged
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.
194Driving and operatingDetecting front pedestrian ahead
A pedestrian ahead up to a distance
of approx. 40 m is indicated by the
control indicator 7 in the instrument
cluster.
Front pedestrian alert
When approaching a detected
pedestrian too quickly, the collision
alert symbol pops up in the Driver Information Centre. A warning chime
is provided. The brake system may
prepare for driver braking to occur
more rapidly which can cause a brief, mild deceleration. Continue to apply
the brake pedal as required.
Cruise control or Adaptive cruise
control may be disengaged when the Front pedestrian alert occurs.
Automatic braking If a crash into a pedestrian directlyahead is imminent, and the brakes
have not been applied, Automatic
braking may automatically brake
moderately or brake hard. This can
help to avoid some very low speed
pedestrian crashes or reduce
pedestrian injury.
Automatic braking levels may be reduced under certain conditions,
such as higher speeds.
If this happens, automatic braking
may engage the Electric parking
brake to hold the vehicle at a stop.
Release the parking brake. Pressing
the accelerator pedal will also release Automatic braking and Electric
parking brake 3 171.
This system includes Intelligent brake assist, and the Emergency automatic
braking system may also respond to
pedestrians.
Active emergency braking 3 190.Automatic braking can be disabled in
the vehicle personalisation menu
3 124.
General information9 Warning
The driver must always be ready
to take action and apply the brakes and steer to avoid collisions.
9 Warning
Front pedestrian braking may alert
or automatically brake the vehicle
suddenly in situations where it is
unexpected and undesired. It
could falsely alert or brake for
objects similar in shape or size to
pedestrians, including shadows.
This is normal operation and the
vehicle does not need a service.
To override Automatic braking,
firmly depress the accelerator
pedal, if it is safe to do so.