188Driving and operating
The selected following distance is
indicated by filled distance bars in the
adaptive cruise control page.
Note that the following distance
setting is shared with the sensitivity
setting of forward collision alert
3 192.
Example: If setting 3 (far) is selected,
then the driver is warned sooner
before a possible collision, also if
adaptive cruise control is inactive or
switched off.
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
The green illuminated vehicle ahead
control indicator A is displayed when
the system detects a vehicle in the driving path.
Forward collision alert 3 192.
If this symbol does not display, or displays only 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.
● Gear 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
15 km/h (on vehicles with
automatic transmission it slows
down to a stop without
deactivating within two minutes).
● The Traction Control system is operating.
● The 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.
Driving and operating189● The collision imminent brakingsystem is applying the brakes.
● The radar sensor is blocked by an ice or water film.
● A fault is detected in the radar, engine or brake system.
Additionally, the system is
automatically deactivated on vehicles
with automatic transmission (full
speed range adaptive cruise control)
when:
● The electric parking brake is applied.
● The vehicle is being held to a stop
by the system for more than
two minutes.
● The vehicle stops, the driver's seat belt is released and the
driver's door is opened.
When adaptive cruise control is
deactivated, the control indicator m
and C in the Driver Information
Centre changes from green to white
and a pop-up message is displayed.
The stored speed is maintained. 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.
Switching off
Press C to switch off adaptive cruise
control. The control indicator m or C
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 need 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 suppresses completely 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.
Driving and operating191Hill and trailer considerations
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. It is not
recommended to use adaptive cruise
control on steep hills.
Radar 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, 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 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 thevehicle personalisation menu in the
Colour-Info-Display.
Select the relevant setting in Settings,
I Vehicle in the Colour-Info-Display.
Colour-Info-Display 3 118.
Vehicle personalisation 3 121.
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.
Driving and operating193
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 Driver Information
Centre.Note that the alert timing sensitivity
setting is shared with the following
distance setting of the adaptive cruise control 3 184. So changing the alert
timing sensitivity changes the
adaptive cruise control following
distance setting.
Alerting 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.
The control indicator A changes to
yellow when the distance to a
preceding moving vehicle gets too
short or when approaching another
vehicle too rapidly.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.
If 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.
194Driving and operatingSettings
Settings can be changed in the
vehicle personalisation menu in the
Colour-Info-Display.
Select the relevant setting in Settings,
I Vehicle in the Colour-Info-Display.
Colour-Info-Display 3 118.
Vehicle personalisation 3 121.
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.
Alerting 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.
When the distance to a preceding
moving vehicle gets too short or when approaching another vehicle too
rapidly and a collision is imminent, the
collision alert symbol pops-up in the
Driver Information Centre.
Simultaneously, 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.
Driving and operating195General 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
Forward collision alert is designed to warn for vehicles only, but may also
react to other objects.
In the following cases, forward
collision alert may not detect a vehicle ahead or sensor performance may be 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,
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 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 3 111.On Baselevel display set Settings
X with the Menu button and select
Following distance indication via the
adjuster wheel on the turn signal lever
3 111.
On Midlevel or Uplevel display, select
Info menu and press o to select
Following distance indication 3 111.
The minimum indicated distance is
0.5 seconds.
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 following
distance setting instead 3 184.
Driving and operating197sudden 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.
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 cases, the active emergency braking 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.
Settings
Settings can be changed in the vehicle personalisation menu in the
Colour-Info-Display.
Select the relevant setting in Settings,
I Vehicle in the Colour-Info-Display.
Colour-Info-Display 3 118.
Vehicle personalisation 3 121.
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 do, vehicle messages are
displayed in the Driver Information
Centre.
Vehicle messages 3 120.
Parking assist
9 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.
198Driving and operatingFront-rear parking assist
The front-rear parking assist
measures the distance between the vehicle and obstacles in front and
behind the vehicle. The system gives acoustic signals and display
messages.
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 from the rear of the vehicle.
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 11 km/h.
An illuminated LED in the parking
assist button r indicates that the
system is ready to operate.
If the vehicle exceeds a speed of
11 km/h, the front parking assist is
deactivated. The front parking assist
is always reactivated when vehicle
speed drops below 11 km/h.
Indication
The system warns the driver with
acoustic signals against potentially
hazardous obstacles behind and in
front of the vehicle. Depending on
which side of the vehicle is closer to
an obstacle, you will hear acoustic warning signals on the respective
side of the vehicle. The interval
between the sounds becomes shorter as the vehicle gets closer to that
obstacle. When the distance is less
than approx. 30 cm, the sound is
continuous.
Additionally, the distance to obstacles is shown in the Driver Information
Centre 3 111.