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rectly. Therefore, make sure that the driver is
rested and alert; otherwise, risks may be de‐
tected too late and an accident be caused as a
result.◀
Function
The system is activated each time the engine
is started and cannot be switched off.
After travel has begun, the system is trained
about the driver, so that increasing lack of
alertness or fatigue can be detected.
This procedure takes the following criteria into
account:▷Personal driving style, for example, steer‐
ing behavior.▷Driving conditions, for example, length of
trip.
Starting at approximately 43 mph/70 km/h, the
system is active and can display a recommen‐
dation to take a break.
Break recommendation
If the driver becomes increasingly less alert or
fatigued, a message is displayed in the Control
Display with the recommendation to take a
break.
A recommendation to take a break is displayed
only once during an uninterrupted trip.
After a break, another recommendation to take
a break cannot be displayed until after approxi‐
mately 45 minutes.
System limits
The function may be limited in the following
situations, for instance, and will either output
an incorrect warning or no warning at all:
▷When the clock is set incorrectly.▷When the vehicle speed is mainly below
about 43 mph/70 km/h.▷With a sporty driving style, such as during
rapid acceleration or when cornering
quickly.▷In active driving situations, such as when
changing lanes frequently.▷When the road surface is poor.▷In the event of strong side winds.
PreCrash
The concept With this system critical driving situations that
might result in an accident can be detected
above a speed of approx. 20 mph/30 km/h. In these situations, preventative protection
measures are automatically undertaken to
minimize the risk in the event of an accident as
much as possible.
Critical driving situations may include:
▷Full brake applications.
If the vehicle includes the collision warning or
collision warning with braking feature, impend‐
ing collisions with vehicles driving ahead or
stopped in front of you can also be detected
within the system's range.
Note Personal responsibility
The system cannot possibly serve as a
substitute for the driver's personal judgment of
the traffic situation. The system may not al‐
ways detect critical situations reliably and in a
timely manner. Adapt speed to traffic situation
and drive alertly; otherwise, a risk to safety may
result.◀
Function
After the safety belt is buckled, the front belts
are automatically pretensioned once after the
vehicle is driven is away.
In critical driving situations, the following indi‐
vidual functions become active as needed:
▷The front belts are automatically preten‐
sioned.▷Automatic closing of the windows.Seite 129SafetyControls129
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▷Automatic closing of the glass sunroof.▷For vehicles equipped with Comfort Seats:
automatic positioning of the backrest for
the front passenger seat.
After a critical driving situation without an acci‐
dent, the front belts are loosened again. All
other systems can be restored to the desired
setting.
If the belt tension does not loosen automati‐
cally, stop the vehicle and unbuckle the belt
using the red button in the buckle. Fasten the
belt before continuing on your trip.
PostCrash
In the event of an accident, the system can
bring the car to a halt automatically without in‐
tervention by the driver in certain situations.
This can reduce the risk of a further collision
and the consequences thereof.
Depressing the brake pedal can cause the ve‐
hicle to brake harder. This interrupts automatic
braking. Depressing the accelerator pedal also
interrupts automatic braking.
After coming to a halt, the brake is released
automatically. Secure the vehicle against roll‐
ing.
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Driving stability control systemsVehicle equipmentAll standard, country-specific and optional
equipment that is offered in the model series is
described in this chapter. Therefore, equip‐
ment is also described that is not available in a
vehicle, e. g., because of the selected optional
equipment or country variant. This also applies
for safety-related functions and systems.
Antilock Brake System ABS ABS prevents locking of the wheels during
braking.
The vehicle remains steerable even during full
brake applications, thus increasing active
safety.
ABS is operational every time you start the en‐
gine.
Brake assistant
When you apply the brakes rapidly, this system
automatically produces the maximum braking
force boost. This then reduces braking dis‐ tance to a minimum during full braking. This
system utilizes all of the benefits provided by ABS.
Do not reduce the pressure on the brake pedal
for the duration of the full braking.
When equipped with Driving Assistant Plus or
with Active Cruise Control with Stop & Go
function, ACC is supported by the braking in‐
tervention if there is a possible risk of collision.
To do this, the braking force is automatically increased if the braking pressure is insufficient
when the brakes are applied.Drive-off assistant
This system supports driving away on gradi‐
ents. The parking brake is not required.1.Hold the vehicle in place with the foot
brake.2.Release the foot brake and drive away
without delay.
After the foot brake is released, the vehicle is
held in place for approx. 2 seconds.
Depending on the vehicle load or when a trailer
is being used, the vehicle may roll back
slightly.
Driving off without delay
After releasing the foot brake, start driv‐
ing without delay, since the drive-off assistant
will not hold the vehicle in place for more than
approx. 2 seconds and the vehicle will begin
rolling back.◀
Automatic Differential Brake
The system controls the driving force by auto‐
matic braking intervention on individual
wheels. The function corresponds to a differ‐
ential lock: the system detects if a wheel be‐
gins to spin, because of loose road surface, for
example, and automatically brakes it.
The driving force is diverted to the wheel with
better traction.
As a result, the engine force is transferred
more efficiently to the wheels during accelera‐
tions.
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Dynamic Performance
Control
The Dynamic Performance Control increases both the agility of the vehicle as well as the
lane stability.
The system seamlessly handles the distribu‐ tion of the drive torque between the two rear
wheels.
Depending on the situation, the drive torque is
shifted from the wheel on the inside of the
curve to the wheel on the outside of the curve
or vice-versa.
To increase the maneuverability, the rear wheel on the outside of the curve is acceler‐
ated when the driving style is correspondingly
sporty.
The steering responds directly; simultane‐
ously, the understeering tendency of the four-
wheel drive is canceled out.
With the oversteering tendency, the system
exerts a stabilizing effect by accelerating the
rear wheel on the inside of the curve.
The system noticeably improves the traction
and simultaneously increases the driving
safety, especially on road surfaces having fluc‐
tuating coefficients of friction.
DSC Dynamic StabilityControl
The concept DSC prevents traction loss in the driving
wheels when driving away and accelerating.
DSC also recognizes unstable vehicle condi‐
tions, such as fishtailing or nose-diving. Sub‐
ject to physical limits, DSC helps to keep the
vehicle on a steady course by reducing engine
speed and by applying brakes to the individual
wheels.Adjust your driving style to the situation
An appropriate driving style is always the
responsibility of the driver.
The laws of physics cannot be repealed, even
with DSC.
Therefore, do not reduce the additional safety
margin by driving in a risky manner.◀
Indicator/warning lamps The indicator lamp flashes: DSC con‐
trols the drive forces and brake forces.
The indicator lamp lights up: DSC has
failed.
Deactivating DSC: DSC OFF
When DSC is deactivated, driving stability is
reduced during acceleration and when driving in bends.
To increase vehicle stability, activate DSC
again as soon as possible.
Deactivating DSC Press and hold the button, but not lon‐
ger than approx. 10 seconds, until the
indicator lamp for DSC OFF lights up in the in‐
strument cluster and DSC OFF is displayed.
The DSC system is switched off.
Activating DSC Press the button.
DSC OFF and the DSC OFF indicator
lamp go out.
Indicator/warning lamps
When DSC is deactivated, DSC OFF is dis‐
played in the instrument cluster.
The indicator lamp lights up: DSC is
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DTC Dynamic Traction
Control
The concept The DTC system is a version of the DSC in
which forward momentum is optimized.
The system ensures maximum forward mo‐
mentum on special road conditions, e.g., unp‐
lowed snowy roads, but driving stability is lim‐
ited.
It is therefore necessary to drive with appropri‐
ate caution.
You may find it useful to briefly activate DTC
under the following special circumstances:▷When driving in slush or on uncleared,
snow-covered roads.▷When rocking the vehicle or driving off in
deep snow or on loose surfaces.▷When driving with snow chains.
Deactivating/activating DTC Dynamic
Traction Control
Activating the Dynamic Traction Control DTC
provides maximum traction on loose ground.
Driving stability is limited during acceleration
and when driving in bends.
Activating DTC Press the button.
TRACTION is displayed in the instru‐
ment cluster and the indicator lamp for DSC
OFF lights up.
Deactivating DTC Press the button again.
TRACTION and the DSC OFF indica‐
tor lamp go out.
Indicator/warning lamps
When DTC is activated, TRACTION is dis‐
played in the tachometer.
The indicator lamp lights up: DTC Dy‐
namic Traction Control is activated.
xDrive xDrive is the all-wheel-drive system of your ve‐
hicle. Concerted action by the xDrive and DSC
further optimize traction and driving dynamics.
The xDrive all-wheel-drive system variably dis‐
tributes the drive forces to the front and rear
axles as demanded by the driving situation and
road surface.
Display on the Control Display
Displaying xDrive view1."Vehicle Info"2."xDrive status"3. "xDrive view"
The following information is displayed:
▷With Professional navigation system: com‐
pass display for the driving direction▷Pitch attitude with degree and percentage▷Transverse gradient with degree indication▷Graphic display for the steering
Displaying distribution of the drive
torque
1."Vehicle Info"2."xDrive status"3. "Torque distribution"
HDC Hill Descent Control
The concept HDC is a downhill driving assistant that auto‐
matically controls vehicle speed on steep
downhill gradients. Without applying the
brakes, the vehicle moves at slightly more than
walking speed.
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Hill Descent Control can be activated at
speeds below approx. 22 mph/35 km/h. When
driving downhill, the vehicle reduces its speed
to approx. walking speed and then keeps its
speed constant.
As long as there is active braking, the system
is on standby. The system does not brake the
vehicle during this time.
Use HDC in low gears or in transmission posi‐
tion D or R only.
Increasing or decreasing vehicle
speed
Specify desired speed in the range from ap‐
prox. 4 mph/6 km/h to approx. 15 mph/25 km/h
using the rocker switch of the cruise control on
the steering wheel. Vehicle speed can be
changed by lightly accelerating.▷Press up the rocker switch to the point of
resistance: the speed increases gradually.▷Press up the rocker switch past the point
of resistance: the speed increases while
the rocker switch is pressed.▷Press down the rocker switch to the point
of resistance: the speed decreases gradu‐
ally.▷Press down the rocker switch past the
point of resistance: when driving forward,
the speed decreases to approx.
6 mph/10 km/h; when reversing, the speed
decreases to approx. 4 mph/6 km/h.Activating HDC
Press the button; the LED above the but‐
ton lights up.
Deactivating HDC Press the button again and the LED goes
out. HDC is automatically deactivated
above approx. 37 mph/60 km/h.
Display in the instrument cluster The selected speed is displayed
in the speedometer.
▷Green: the system is actively
braking the vehicle.▷Orange: the system is on
standby.
Malfunction
A message is displayed in the instrument clus‐
ter. HDC is not available, e.g., due to elevated
brake temperatures.
Active Steering
Active Steering varies the steering angle of the
wheels in relation to the steering wheel move‐
ment as a function of the speed.
At lower speeds, for example during turning or
maneuvering, the steering angle is increased,
that is to say the steering becomes more di‐
rect.
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At higher speeds, the steering angle is increas‐
ingly reduced.
This enables even more precise handling at
high speeds and more responsive steering
with reduced steering angle at low speeds.
Active roll stabilization
The concept The system reduces the lateral inclination of
the vehicle that occurs during rapid driving in
curves or during quick evasive maneuvers.
Driving stability and driving comfort are in‐
creased under all driving conditions. The sys‐
tem utilizes active stabilizer bars on the front
and rear axles that react immediately to all driv‐
ing situations.
Programs The system offers two different programs.
The programs can be selected via the Driving
Dynamics Control, refer to page 135.
SPORT
Sporty tuning for greater driving agility.
COMFORT
Comfort-oriented tuning for optimal comfort.
Vertical Dynamic Control The concept This system reduces undesirable vehicle mo‐
tion when using a dynamic driving style or trav‐
eling on uneven road surfaces.
The system enhances driving dynamics and
comfort as required for the road surface and
driving style.
Programs The system offers several different programs.The programs can be selected via the Driving
Dynamics Control, refer to page 135.
SPORT/SPORT+
Consistently sporty control of the shock ab‐
sorbers for greater driving agility.
COMFORT/ECO PRO Balanced tuning.
Self-leveling suspension The concept The self-leveling suspension keeps the vehicle
height and ground clearance constant. The
height of the vehicle at the rear axle is main‐
tained at a predefined level under all load con‐
ditions.
The system ensures consistent comfort by
keeping spring travel constant in all driving sit‐
uations.
Malfunction
A Check Control message is displayed. A mal‐ function has occurred in the self-leveling sus‐
pension. Vehicle handling may be altered and
driving comfort may be noticeably reduced.
Visit your nearest service center.
Driving Dynamics ControlThe concept
The Driving Dynamics Control can be used to
adjust the driving dynamics of the vehicle. For
this purpose various programs are available for
selection that are activated via the two buttons
of the Driving Dynamics Control and the DSC
OFF-button.Seite 135Driving stability control systemsControls135
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Operating the programsPress the buttonProgramDSC OFF
TRACTIONSPORT+
SPORT
COMFORT
ECO PRO
Automatic program change
The system may automatically switch to COM‐
FORT in the following situations:
▷The vehicle has a flat tire.▷Failure of Dynamic Damping Control, Dy‐
namic Drive or xDrive.
DSC OFF
Driving stability is limited during acceleration
and when driving in bends.
To increase vehicle stability, activate DSC
again as soon as possible.
Deactivating DSC: DSC OFF Press and hold the button, but not lon‐
ger than approx. 10 seconds, until the
indicator lamp for DSC OFF lights up in the in‐
strument cluster and DSC OFF is displayed in
the tachometer.
The DSC system is switched off.
Activating DSC Press the button.
DSC OFF and the DSC OFF indicator
lamp go out.
Indicator/warning lamps
When DSC OFF is activated, DSC OFF is dis‐
played in the tachometer.
The indicator lamp lights up: DSC OFF
is activated.
TRACTION Maximum traction on loose road surfaces. DTC
Dynamic Traction Control is switched on. Driv‐
ing stability is limited during acceleration and
when driving in bends.
Activating TRACTION Press the button.
TRACTION is displayed in the tach‐
ometer.
The DSC indicator lamp in the instrument clus‐
ter lights up.
Deactivating TRACTION Press the button again.
TRACTION and the DSC indicator
lamp go out.
Indicator/warning lamps
When TRACTION is activated, TRACTION is
displayed in the tachometer.
The indicator lamp lights up: TRAC‐
TION is activated.
SPORT+ Sporty driving with optimized chassis and
adapted engine control with limited driving sta‐
bilization.
Dynamic Traction Control is switched on. The driver handles several of the stabilization
tasks.
Activating SPORT+ Press the button repeatedly until
SPORT+ appears in the tachometer
and the DSC OFF indicator lamp lights up in
the instrument cluster.Seite 136ControlsDriving stability control systems136
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