186Driving and operating
The stored speed is maintained.
9Warning
When adaptive cruise control is
deactivated, the driver must take
over full brake and engine control.
Switching off
Press C to switch off adaptive cruise
control. The control indicator m
extinguishes. The stored speed is
deleted.
Switching off the ignition also
switches off adaptive cruise control
and deletes the stored speed.
Driver's attention
● Use adaptive cruise control carefully on bends or mountain
roads, as it can lose the vehicle
ahead and require 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.
● Do not use 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 completely suppresses the
visibility. In case of sensor
blockage, clean the sensor
cover.
System limits ● 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.
● Adaptive cruise control does ignore the oncoming traffic.
● Adaptive cruise control does not brake for stopped vehicles,
pedestrians or animals.
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
188Driving and operatingRadar unit
The radar unit is mounted behind the
radiator grille below the brand
emblem.
9 Warning
The radar unit was aligned
carefully during manufacture.
Therefore, after a frontal accident, do not use the system. The front
bumper may appear to be intact,
however the sensor behind can be
out of position and react
incorrectly. After an accident,
consult a workshop to verify and
correct the adaptive cruise control
sensor position.
Settings
Settings can be changed in the Auto
collision preparation menu in the
vehicle personalisation 3 129.
Fault
If the adaptive cruise control does not
work due to temporary conditions
(e.g. blockage by ice) or if there is a
permanent system error, then a
message is displayed in the Driver
Information Centre.
Vehicle messages 3 122.
Forward collision alert The forward collision alert can help to
avoid or reduce the damage caused
by front-end crashes.
A vehicle ahead is indicated by a
control indicator A.
Driving and operating189
If a vehicle directly ahead is
approached too quickly, a warning
chime and alert in the Driver
Information Centre is provided.
A precondition is that forward collision
alert is activated in the vehicle
personalisation menu 3 129 or that it
is not deactivated by pressing V
(depending on the system, see
following).
Depending on the vehicle's
equipment, there are two variants of
the forward collision alert available:
● Forward collision alert based on
radar system
on vehicles equipped with
adaptive cruise control 3 182.
● Forward collision alert based on
front camera system
on vehicles with traditional cruise
control or none 3 179.
Forward collision alert based on
radar system
The system uses the radar sensor
behind the radiator grille to detect a
vehicle directly ahead, in your path,
within a distance of max. 150 metres.
Activation
Forward collision alert operates
automatically above walking speed,
provided that Auto collision
preparation setting is not deactivated
in the vehicle personalisation menu
3 129.
Selecting the alert sensitivity
The alert sensitivity can be set to
near, medium or far.
Press E; the current setting is shown
in the Driver Information Centre.
Press E again to change the alert
sensitivity. The setting is also displayed in the top line of the Driver
Information Centre.
192Driving and operatingapproaching 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.
System limitations
The system is designed to warn only for vehicles, but may react also onother metallic objects.
In the following cases, forward
collision alert may not detect a vehicle ahead or sensor performance is
limited:
● on winding roads
● when weather limits visibility, such as fog, rain, or snow
● when the sensor is blocked by snow, ice, slush, mud, dirt, or
windscreen damage
Following distance
indication
The following distance indication
displays the distance to a preceding
moving vehicle. The system uses,
depending on the vehicle equipment,
either the radar behind the radiator
grille or the front camera in the
windscreen to detect the distance of
a vehicle directly ahead in your lane.
It is active at speeds above 25 mph.
When a preceding vehicle is detected ahead, the distance is indicated inseconds, displayed on a page in the
Driver Information Centre 3 116.
Press MENU on the turn signal lever
to select Vehicle Information Menu
X and turn the adjuster wheel to
choose following distance indication
page.
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 toreduce 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 3 188.
Driving and operating193The 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
3 129.
The system includes: ● brake preparation system
● emergency automatic braking
● forward looking brake assist9Warning
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
results immediately in a strong
braking. This function helps the driver
brake quicker and stronger before the imminent collision.9 Warning
Active emergency braking is not
designed to apply strong
autonomous braking or to avoid automatically a collision. It is
designed to reduce the vehicle
speed before collision. It may not
react on stopped vehicles,
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 wearing their seat belts.
System limitations
The active emergency braking has
limited or no function during rain,
snow or heavy dirt, as the radar
sensor can be covered by a water
194Driving and operatingfilm, dust, ice or snow. In case of
sensor blockage, clean the sensor
cover.
In some seldom cases the active
emergency braking system may
provide a short automatic braking in
situations that seem to be
unnecessary, for instance due to
traffic signs in a curve or due to
vehicles in another lane. This is
acceptable operation, the vehicle
does not need service. Firmly apply
the accelerator pedal to override the automatic braking.
Settings Settings can be changed in the Auto
collision preparation menu in the
vehicle personalisation, 3 129.
Fault
In the event of a system service
requirement, a message is displayed
in the Driver Information Centre.
If the system does not work as it
should, vehicle messages are
displayed in the Driver Information
Centre.
Vehicle messages 3 122.
Parking assist
Front-rear parking assist9 Warning
The driver bears full responsibility
for the parking manoeuvre.
Always check the surrounding
area when driving backwards or
forwards while using parking
assist system.
The front-rear parking assist
measures the distance between the vehicle and obstacles in front of and
behind the vehicle. The system gives acoustic signals and display
messages.
Driving and operating195
The system has four ultrasonic
parking sensors each in the rear and
front bumper.
It uses two different acoustic warning
signals for the front and rear
monitoring areas, each with a
different tone frequency. The signal
for front obstacles sounds via the
front speakers, for rear obstacles it
sounds via the rear speakers.
Parking assist button D and
operation logic
Front-rear parking assist is equipped
with D. If the vehicle is additionally
equipped with advanced parking
assist (see the following separate
description), both systems will be
operated by pressing D.
Short press on D deactivates or
activates the front parking assist.
Long press on D (approx.
one second) activates or deactivates
the advanced parking assist.
Button logic to operate the systems is as follows:
● Front-rear parking assist is active: short press deactivates
front-rear parking assist.
● Front-rear parking assist is active: long press activates
advanced parking assist if a
forward gear is engaged.
● Advanced parking assist is active: short press activates
front-rear parking assist.
● Advanced parking assist is active: long press deactivates
advanced parking assist.
● Advanced parking assist and front-rear parking assist are
active: short press deactivates
both systems.
Activation
When reverse gear is engaged, the
front and rear parking assist is ready
to operate.
The front parking assist is also
activated automatically at a speed up
to 7 mph.
Driving and operating197After a manual deactivation, the front
parking assist is activated again if
D is pressed or if reverse gear is
engaged.
Fault
In the event of a fault in the system or
if the system does not work due to
temporary conditions, e.g. ice
covered sensors, control indicator
r illuminates or a message is
displayed in the Driver Information
Centre.
Vehicle messages 3 122.
Control indicator r 3 113.
Advanced parking assist9 Warning
The driver bears full responsibility
for accepting the parking slot
suggested by the system and the
parking manoeuvre.
Always check the surrounding
area in all directions when using
advanced parking assist.
The advanced parking assist system manoeuvres the driver into a parkingslot by giving instructions on the
Driver Information Centre and via
acoustic signals. The driver must
control acceleration, braking, steering
and gearshifting.
The system uses the sensors of the
front-rear parking assist in
combination with two additional
sensors on both sides of the front and rear bumper.
Parking assist button D and
operation logic
Advanced parking assist and front-
rear parking assist (see previous
description) are both operated by
pressing D.
Short press on D deactivates or
activates the front parking assist.
Long press on D (approx.
one second) activates or deactivates the advanced parking assist.
Button logic to operate the systems is as follows:
● Front-rear parking assist is active: short press deactivates
front-rear parking assist.
● Front-rear parking assist is active: long press activates
advanced parking assist if a
forward gear is engaged.
● Advanced parking assist is active: short press activates
front-rear parking assist.