Driving and operating173ABS starts to regulate brake pressure
as soon as a wheel shows a tendency to lock. The vehicle remains
steerable, even during hard braking.
ABS control is made apparent
through a pulse in the brake pedal
and the noise of the regulation
process.
For optimum braking, keep the brake
pedal fully depressed throughout the
braking process, despite the fact that
the pedal is pulsating. Do not reduce
the pressure on the pedal.
After starting off, the system performs a self-test which may be audible.
Control indicator u 3 106.
Adaptive brake light During full braking, all three brake
lights flash for the duration of ABS
control.
Fault9 Warning
If there is a fault in the ABS, the
wheels may be liable to lock due
to braking that is heavier than
normal. The advantages of ABS are no longer available. During
hard braking, the vehicle can no longer be steered and may
swerve.
Have the cause of the fault remedied
by a workshop.
Parking brake
Manual parking brake9 Warning
Always apply parking brake firmly
without operating the release
button, and apply as firmly as
possible on a downhill or uphill
slope.
To release the parking brake, pull
the lever up slightly, press the
release button and fully lower the
lever.
178Driving and operating● Antilock Brake System (ABS)with cornering brake control
(CBC)
● Automatic transmission
SPORT mode
The settings of the systems are
adapted to a sportier driving style:
● Damping of shock absorbers reacts more stiffly to providebetter contact with the road
surface.
● The engine reacts more quickly to the accelerator pedal.
● Steering support is reduced.
● Engine torque of All-wheel drive is distributed more to the rear
axle.
● Shift points of automatic transmission occur later.
● Depending on the instrument cluster the colouring of the
display will be adapted.
TOUR mode
The settings of the systems are
adapted to a comfort driving style:
● Damping of shock absorbers reacts more softly.
● Accelerator pedal reacts with standard settings.
● Steering support is in standardmode.
● Engine torque of All-wheel drive is distributed mainly to the front
axle.
● Shift points of automatic transmission occur in a comfort
mode.
NORMAL mode
All settings of the systems are
adapted to standard values.
Drive mode control
Within each manually selected driving mode SPORT, TOUR or NORMAL,
the Drive Mode Control (DMC)
detects and analyses continuously the real driving characteristic,
responses by the driver, and the
active dynamic state of the vehicle. If
necessary, the control unit of DMC
automatically changes the settings
within the selected driving mode or, when recognising greater variations,
the driving mode is changed for the
length of variation.
Driving and operating179If, for example, NORMAL mode is
selected and DMC detects a sporty
driving behaviour, DMC changes
several settings of the Normal mode
into sporty settings. The DMC
changes to SPORT mode in case of
very sporty driving behaviour.
If, for another example, TOUR mode
is selected and whilst driving on a
winding road a sudden hard brake is
necessary, DMC will detect the
dynamic vehicle condition and
changes the settings for suspension
to SPORT mode to increase vehicle
stability.
When the driving characteristic or the
dynamic vehicle state returns to the
former state, DMC will change the
settings to the preselected driving
mode.
Personalised settings in SPORT
mode
The driver can select the functions of
the SPORT mode when SPORT is
pressed.
Select the relevant settings in
Settings , I Sport Mode in the Colour-
Info-Display.Colour-Info-Display 3 117.
Vehicle personalisation 3 121.
Flex Ride - VXR Version The VXR Version of Flex Ride system
works in the same way as the
standard Flex Ride system with the
difference that the modes have a
more sporty characteristic.VXR Flex Ride driving system allows
the driver to select between three
driving modes:
● VXR mode: press VXR, LED
illuminates.
● SPORT mode: press SPORT,
LED illuminates.
● NORMAL mode: neither SPORT
nor VXR is pressed, no LED
illuminates.
Deactivate SPORT mode and VXR
mode by pressing corresponding
button once more.
In each driving mode VXR Flex Ride
networks the following electronic
systems:
● Continuous Damping Control
● Accelerator Pedal Control
● Steering Control
● All-wheel drive
● Electronic Stability Control (ESC)
● Antilock Brake System (ABS) with cornering brake control
(CBC)
● Automatic transmission
Driving and operating1879Warning
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 3 190.
If this symbol does not display, or displays 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
120 mph or slows down below
9 mph (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.● The collision imminent braking system 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 safety belt is released and the
driver's door is opened.
When adaptive cruise control is
deactivated automatically, the control indicator m or C illuminates white
and a warning message is displayed
as a pop-up in the Driver Information
Centre.
The stored speed is maintained.
188Driving and operating9Warning
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.● Adaptive cruise control does notbrake 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.
190Driving 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
vehicle personalisation menu in the
Colour-Info-Display.
Select the relevant setting in Settings,
I Vehicle in the Colour-Info-Display.
Colour-Info-Display 3 117.
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.
Vehicle messages 3 119.
Forward collision alert The forward collision alert can help to
avoid or reduce the harm caused by
front-end crashes.
A vehicle ahead is indicated by a
control indicator A.
194Driving and operatingIn 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, e.g. 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 in
seconds, displayed on a page in the
Driver Information Centre 3 110.On Baselevel display set Settings
X with the Menu button and select
Following distance indication via the
adjuster wheel on the turn signal lever
3 110.
On Midlevel or Uplevel display, select
Info menu and press o to select
Following distance indication 3 110.
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 3 183.
Active emergency braking
Active emergency braking can help to reduce 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 3 190.
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
3 121.
The system includes: ● brake preparation system
● emergency automatic braking
● forward looking brake assist
Driving and operating1959Warning
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. The driver must 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.
Below a speed of 11 mph the system
can apply full braking.
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,
depressing the brake pedal less
strongly results in immediate hard
braking. This function helps the driver
brake quicker and harder before the
imminent collision.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 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 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.