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172Driving and operating
ABS starts to regulate brake pressureas 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 3 115.
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 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 3 114.
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Driving and operating1759Warning
Do not let this special safety
feature tempt you into taking risks
when driving.
Adapt speed to the road
conditions.
Control indicator b 3 116.
Deactivation
TC can be switched off when spinning of drive wheels is required:
press button b briefly to deactivate
TC, k illuminates. Deactivation is
displayed as status message in the
Driver Information Centre.
TC is reactivated by pressing the b
button again.
TC is also reactivated the next time
the ignition is switched on.
Electronic Stability Control Electronic Stability Control (ESC)
improves driving stability when
necessary, regardless of the type of
road surface or tyre grip. It also
prevents the drive wheels from
spinning. ESC operates in
combination with the Traction Control system (TC) 3 174.
As soon as the vehicle starts to
swerve (understeer/oversteer),
engine output is reduced and the wheels are braked individually. This
considerably improves the driving stability of the vehicle on slippery road
surfaces.ESC is operational after each engine
start as soon as the control indicator
b extinguishes.
When ESC operates b flashes.9 Warning
Do not let this special safety
feature tempt you into taking risks
when driving.
Adapt speed to the road
conditions.
Control indicator b 3 116.
Deactivation
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Driving and operating179
NORMAL mode
In NORMAL mode, when neither
SPORT nor VXR button is pressed,
all settings of the systems are
adapted to standard values.
SPORT mode
The settings of the systems are
adapted to a sportier driving style.
VXR mode
The drive dynamic characteristics are adapted to high performance
settings.
In this mode the illumination of main
instruments is switched to red.
Personalised settings in the VXR
mode
The driver can select the functions of
the VXR mode when VXR button is
pressed. These settings can be changed in the menu Settings in the
Info-Display. Vehicle personalisation 3 132.Driver assistance
systems9 Warning
Driver assistance systems are
developed to support the driver
and not to replace the driver's
attention.
The driver accepts full
responsibility when driving the
vehicle.
When using driver assistance
systems, always take care
regarding the current traffic
situation.
Cruise control
The Cruise control can store and
maintain speeds of approx. 20 to
120 mph. Deviations from the stored
speeds may occur when driving uphill or downhill.
For safety reasons the cruise controlcannot be activated until the foot
brake has been operated once.
Activating in first gear is not possible.
Do not use the cruise control if it is not advisable to maintain a constant
speed.
With automatic transmission, only
activate cruise control in automatic
mode.
Control indicator m 3 119.
Switching on Press button m, control indicator m in
instrument cluster illuminates white.
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Driving and operating1839Warning
The complete driver attention is
always required while driving with adaptive cruise control. The driver stays fully in control of the vehicle
because the brake pedal, the
accelerator pedal and the cancel
switch have priority over any
adaptive cruise control operation.
Switching on
Press button C to switch on adaptive
cruise control. The control indicator
m illuminates white.
Activation by setting the speed
Adaptive cruise control can be
activated between 31 mph and
112 mph.
Accelerate to the desired speed and
turn thumb wheel to SET/-, the
current speed is stored and
maintained. Control indicator m
illuminates green.
The adaptive cruise control symbol,
the following distance setting and set speed are indicated in the top line ofthe Driver Information Centre.
The accelerator pedal can be
released. Adaptive cruise control
remains activated while gearshifting.
Overriding set speed It is always possible to drive faster
than the selected set speed by
depressing the accelerator pedal.
When the accelerator pedal is
released, the vehicle returns to the
desired distance if a slower vehicle is
ahead. Otherwise it returns to the
stored speed.
Once the system is activated,
adaptive cruise control decelerates or
brakes if it detects a vehicle ahead,
which is slower or closer than the
desired following distance.9 Warning
Accelerating by the driver
deactivates automatic braking by
the system. This is indicated as a
pop-up warning in the Driver
Information Centre.
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Driving and operating185
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.
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 in the
speedometer when the system
detects a vehicle in the driving path.
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:
■ 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 slows down below 28 mph or accelerates above
120 mph,
■ Traction Control system is operating for more than
20 seconds,
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186Driving and operating
■ Electronic Stability Control isoperating,
■ 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,
■ 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.
When adaptive cruise control is
deactivated automatically, the control
indicator m 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 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.
■ 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 todetect the next preceding vehicle.
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188Driving and operating
Hill and trailer considerations
System performance on hills and
when towing a trailer depends on your
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.
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, 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, 3 132.
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.
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Driving and operating189
Vehicle messages 3 126.
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.
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 3 132 or that it
is not deactivated by the button 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 maximum distance of
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
3 132.
Selecting the alert sensitivity
The alert sensitivity can be set to
near, medium or far.