Driving and operating175The preset speed limit is displayed in
the Driver Information Centre when
the system is active.
Activation
Press L. Symbol Lilluminates in the
Driver Information Centre.
If cruise control or adaptive cruise control has been activated before, it
is switched off when speed limiter is
activated and the control indicator m
extinguishes.
Set speed limit
Accelerate to the desired speed and
briefly turn thumb wheel to SET/-: the
current speed is stored as maximum speed. L and the speed limit is
displayedin the Driver Information
Centre.
Change speed limit
With speed limiter active, turn thumb
wheel to RES/+ to increase or SET/-
to decrease the desired maximum
speed.
Exceeding the speed limit
When exceeding the limited speed
without driver input, the speed will
flash in the Driver Information Centre
and a chime sounds during this
period.
In the event of an emergency, it is
possible to exceed the speed limit by
depressing the accelerator pedal
firmly nearly to the final point. In this
case no chime appears.
Release the accelerator pedal and
the speed limiter function is
reactivated once a speed lower than
the limit speed is obtained.
Deactivation Press y: speed limiter is deactivated
and the vehicle can be driven without speed limit.
The stored limited speed is indicated
in brackets. Additionally, a
corresponding message appears.
Speed limiter is deactivated, but not
switched off. Last stored speed
remains in memory for later speed
resume.
Driving and operating1799Warning
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
The green illuminated vehicle ahead
control indicator A is displayed when
the system detects a vehicle in the driving path.
Forward collision alert 3 182.
If this symbol does not appear, or appears briefly, adaptive cruise
control will not respond to vehicles
ahead.
Deactivation
Adaptive cruise control is deactivated by the driver when:
● y is pressed.
● Brake pedal is applied.
● Clutch pedal is depressed for more than four seconds.
● Selector lever of automatic transmission is moved to N.
The system is also automatically deactivated when:
● Vehicle speed accelerates above
190 km/h or slows down below
45 km/h.
● The Traction Control system is operating.
● Electronic Stability Control is operating.
● There is no traffic and nothing detected on the road sides for
several minutes. In this case
there are no radar echoes and
the sensor may report that it is
blocked.
● The active emergency braking system is applying the brakes.● Driving on steep inclines.
● Radar sensor is blocked by an ice
or water film.
● A fault is detected in the radar, engine or brake system.
When adaptive cruise control is
deactivated, the control indicator m
changes from green to white and a
pop-up message is displayed in the
Driver Information Centre.
The stored speed is maintained and
indicated in brackets in the Driver
Information Centre. The system is
deactivated but not switched off.
9 Warning
When adaptive cruise control is
deactivated, the driver must take
over full brake and engine control.
180Driving and operatingSwitching off
Press C to switch off adaptive cruise
control. The control indicator m and
C in the Driver Information Centre
extinguish. 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 of the vehicle.
● 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 thevisibility. 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 pedestrians, animals,very slow speed driving or
stopped vehicles.
● Don't use adaptive cruise control when towing a trailer.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
longer 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
Driving and operating181entering 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 in
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 if 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 and trailer considerations
System performance on hills and
when towing a trailer 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, especially
when towing a trailer, you may have
to brake to maintain or reduce your
speed.
Note that applying the brake
deactivates the system. It is not
recommended to use adaptive cruise
control on steep hills especially when towing a trailer.
184Driving and operatingCaution
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.
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 and a
warning chime sounds. Depress the
brake pedal, if it is required by the
situation.
Settings
Settings can be changed in the
vehicle personalisation menu in the
Info-Display.
Select the relevant setting in
Settings in the Info-Display.
Vehicle personalisation 3 125.
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 40 km/h, if it is not deactivated by pressing V, see
below.
Selecting the alert sensitivity
The alert sensitivity can be set to
near, medium or far.
Press V; the current setting is shown
in the Driver Information Centre.
Press V again to change the alert
sensitivity.
Driving and operating185Alerting the driver
The vehicle ahead control indicator
A illuminates green in the instrument
cluster when the system has detected
a vehicle in the driving path.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.
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 and a
warning chime sounds. Depress the
brake pedal, if it is required by the
situation.
Deactivation
The system can be deactivated.
Press V repeatedly until Forward
Collision Alert Off appears in the
Driver Information Centre.
General information for both
variants of forward collision alert9 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.
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,
windscreen damage or affected
by foreign items, e.g. stickers
Following distance indication
The following distance indication
displays the distance to a preceding
moving vehicle. The system uses,
186Driving and operatingdepending 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 path. It is active at speeds above 40 km/h.
When a preceding vehicle is detected
ahead, the distance is indicated in
seconds, displayed on a page in the
Driver Information Centre 3 117.
Press MENU on the turn signal lever
to select Vehicle Information
Menu ? 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.
If Adaptive cruise control is active,
this page shows the alert sensitivity
setting instead of following distance setting. 3 176.
Active Emergency Braking
Active emergency braking can help to reduce 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 3 182.
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
3 125.
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.
Driving and operating187Brake preparation system
When approaching a vehicle ahead
so quickly that a collision is likely, the brake preparation system slightlypressurises 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
film, 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
vehicle personalisation menu in the
Info-Display.
Select the relevant setting in
Settings in the Info-Display.
Vehicle personalisation 3 125.
Fault
In the event of a system service
requirement, a message is displayed
in the Driver Information Centre.