164Driving and operating
Fault9Warning
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 brake
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.
To reduce the operating forces of the
parking brake, depress the foot brake
at the same time.
Control indicator R 3 102.
Electric parking brake
Applying when vehicle is stationary
Pull switch m for approx.
one second, the electric parking
brake operates automatically with an adequate force. For maximum force,
e.g. parking with trailer or on inclines,
pull switch m twice.
The electric parking brake is applied
when control indicator m lights up
3 102.
The electric parking brake can always
be activated, even if the ignition is off.
168Driving and operating
Additionally the selected mode is
displayed as status message in the
Driver Information Centre.
If the vehicle comes into threshold
with deactivated ESP, the system will reactivate ESP for the time duration
of the threshold, when the brake pedal is depressed once.
ESC is reactivated by pressing the
b button again. If the TC system was
previously disabled, both TC and
ESC are reactivated.
ESC is also reactivated the next time
the ignition is switched on.Interactive driving system
Flex Ride Flex Ride driving system allows the
driver to select between three driving
modes:
■ SPORT mode: press button SPORT , LED illuminates.
■ TOUR mode: press button TOUR,
LED illuminates.
■ NORMAL mode: neither button SPORT nor TOUR is pressed, no
LED illuminates.
Deactivate SPORT mode and TOUR
mode by pressing corresponding
button once more.
In each driving mode 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.
SPORT mode
The settings of the systems are
adapted to a sportier driving style:
■ Damping of shock absorbers reacts
more stiffly to provide better 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.
170Driving and operating
Flex Ride - OPC VersionThe OPC Version of Flex Ride systemworks in the same way as the
standard Flex Ride system with the
difference that the modes have a
more sporty characteristic.OPC Flex Ride driving system allows
the driver to select between three
driving modes:
■ OPC mode: press button OPC,
LED illuminates.
■ SPORT mode: press button SPORT , LED illuminates.
■ NORMAL mode: neither button SPORT nor OPC is pressed, no
LED illuminates.
Deactivate SPORT mode and OPC mode by pressing corresponding
button once more.
In each driving mode OPC 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.OPC mode
The drive dynamic characteristics are adapted to high performance
settings.
In this mode the illumination of main
instruments is switched to red.
SPORT mode
The settings of the systems are
adapted to a sportier driving style.
NORMAL mode
In NORMAL mode, when neither
SPORT nor OPC button is pressed,
all settings of the systems are
adapted to standard values.
Personalised settings in the OPC
mode
The driver can select the functions of
the OPC mode when OPC button is
pressed.
Select the relevant settings in
Settings , I Sport Mode in the Colour-
Info-Display.
Colour-Info-Display 3 114.
Vehicle personalisation 3 118.
178Driving and operating
Deactivation
Adaptive cruise control is deactivated by the driver when:
■ button 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 below15 km/h (on vehicles with automatic transmission it slows down to a stop
without deactivating within
two minutes),
■ Traction Control system is operating for more than
20 seconds,
■ Electronic Stability Control is operating,■ there is no traffic and nothingdetected on the road sides for
several minutes. In this case there
are no radar echoes and the sensor
may report that it is blocked,
■ collision imminent braking is applying the brakes,
■ radar sensor is blocked by an ice or
water film,
■ 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:
■ Electric parking brake is applied,
■ vehicle is being held to a stop by the
system for more than two minutes,
■ vehicle stops and a door is opened.
When adaptive cruise control is
deactivated automatically, the control indicator m or C illuminates white
and a warning symbol is displayed as a pop-up in the Driver Information
Centre.
The stored speed is maintained.
9 Warning
When adaptive cruise control is
deactivated, the driver must take
over full brake and engine control.
Switching off
Press button 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.
Driving and operating179
Driver's attention■ Use adaptive cruise control carefully on bends or mountainroads, 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 completelythe 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 pedestrians, animals or
stopped vehicles.
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
entering 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 on
the driving path or not. Adaptive
cruise control may not be able to
Driving and operating181consult 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 3 114.
Vehicle personalisation 3 118.
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 3 116.
Forward collision alert
The forward collision alert can help to
avoid or reduce the harm caused by
front-end crashes. If a vehicle directly
ahead is approached too quickly, a
warning chime and alert in the Driver
Information Centre is provided.
The green illuminated vehicle ahead
symbol A appears in the instrument
cluster when the system has detected
a vehicle in the driving path. A
precondition is that forward collision
alert is activated in the vehicle
personalisation menu 3 118 or that it
is not deactivated by the button V
(depending on the system, see
below).
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 3 173.
■ Forward collision alert based on
front camera system
on vehicles with no cruise control or
traditional cruise control only
3 171.
184Driving and operating
Deactivation
The system can be deactivated.
Press button 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 to
other metallic 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, 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 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 3 107.
On Baselevel display set Settings
X with the Menu button and
select Following distance indication
via the adjuster wheel on the turn signal lever 3 107.
On Midlevel or Uplevel display, select
Info menu and press o to
select Following distance indication
3 107.
The minimum indicated distance is
0.5 seconds.
186Driving and operatingpedestrians 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 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
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 3 114.
Vehicle personalisation 3 118.
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 3 116.