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GWARNING
If children are travelling in the vehicle, they
could:
R open doors, thus endangering other people
or road users
R exit the vehicle and be caught by oncoming
traffic
R operate vehicle equipment and become
trapped, for example
There is a risk of an accident and injury.
Always activate the child-proof locks and
override feature if children are travelling in the
vehicle. When leaving the vehicle, always take
the key with you and lock the vehicle. Never
leave children unattended in the vehicle.
You can activate the following child-proof
locks:
R rear doors ( Y page 63)
R rear side windows ( Y page 63)
Child-proof locks for the rear doors
You secure each door individually with the
child-proof locks on the rear doors. A door
secured with a child-proof lock cannot be
opened from inside the vehicle. When the
vehicle is unlocked, the door can be opened
from the outside.
XTo activate: press the child-proof lock
lever up in the direction of arrow :.XMake sure that the child-proof locks are
working properly.XTo deactivate: press the child-proof lock
lever down in the direction of arrow ;.
Override feature for the rear side win-
dows
XTo activate/deactivate: press button :.
If indicator lamp ; is lit, operation of the
rear side windows is disabled. Operation is
only possible using the switches in the driv-
er's door. If indicator lamp ; is off, oper-
ation is possible using the switches in the
rear compartment.
Driving safety systems
Driving safety systems overview
In this section, you will find information about
the following driving safety systems:
R ABS ( Anti-lock Braking System)
( Y page 64)
R BAS ( Brake Assist System) ( Y page 64)
R COLLISION PREVENTION ASSIST (adaptive
Brake Assist and distance warning func-
tion) ( Y page 65)
R Adaptive brake lamps ( Y page 68)
R ESP ®
(E lectronic Stability Program)
( Y page 68)
R EBD ( electronic brake force distribution)
( Y page 70)
R ADAPTIVE BRAKE ( Y page 70)
R STEER CONTROL ( Y page 70)
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Important safety notes
If you fail to adapt your driving style or if you
are inattentive, the driving safety systems can
neither reduce the risk of accident nor over-
ride the laws of physics. Driving safety sys-
tems are merely aids designed to assist driv-
ing. You are responsible for the distance to
the vehicle in front, for vehicle speed and for
braking in good time. Always adapt your driv-
ing style to suit the prevailing road, weather
and traffic conditions and maintain a safe dis-
tance from the vehicle in front. Drive care-
fully.
i The driving safety systems described only
work as effectively as possible when there
is adequate contact between the tyres and
the road surface. Pay particular attention
to the information regarding tyres, recom-
mended minimum tyre tread depths etc. in
the "Wheels and tyres" section
( Y page 316).
In wintry driving conditions, always use
winter tyres (M+S tyres) and, if necessary,
snow chains. Only in this way will the driv-
ing safety systems described in this section
work as effectively as possible.
ABS (Anti-lock Braking System)
General notes
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the vehi-
cle when braking.
The ! ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems
( Y page 64).
GWARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid-
ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
If ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp ( Y page 256) and
display messages which may be shown in the
instrument cluster ( Y page 227).
ABS works from a speed of about
8 km/hupwards, regardless of road-surface
conditions. ABS works on slippery surfaces,
even when you only brake gently.
Braking
XIf ABS intervenes: continue to depress the
brake pedal with force until the braking sit-
uation is over.XTo make a full brake application:
depress the brake pedal with full force.
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
The pulsating brake pedal can be an indica-
tion of hazardous road conditions, and func-
tions as a reminder to take extra care while
driving.
BAS (Brake Assist)
General notes
BAS operates in emergency braking situa-
tions. If you depress the brake pedal quickly,
BAS automatically boosts the braking force,
thus shortening the stopping distance.
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Important safety notes
iObserve the "Important safety notes" sec-
tion ( Y page 64).
GWARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
Braking
XKeep the brake pedal depressed firmly until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated.
COLLISION PREVENTION ASSIST
General notes
COLLISION PREVENTION ASSIST consists of
the adaptive Brake Assist and the distance
warning signal, which are described in the
following.
Distance warning function
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems
( Y page 64).
GWARNING
The distance warning function does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
Thus, the distance warning function cannot
provide a warning in all critical situations.
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
The distance warning function cannot always
clearly identify objects and complex traffic
situations.
In such cases, the distance warning function
may:
R give an unnecessary warning
R not give a warning
Always pay careful attention to the traffic sit-
uation; do not rely on the distance warning
function alone.
FunctionXTo activate/deactivate: activate or deac-
tivate the distance warning function in the
on-board computer ( Y page 218).
If the distance warning function is not activa-
ted, the æ symbol appears in the assis-
tance graphics display.
The distance warning function can help you
to minimise the risk of a front-end collision
with a vehicle ahead or reduce the effects of
such a collision. If the distance warning func-
tion detects that there is a risk of a collision,
you will be warned visually and acoustically.
Without your intervention, the distance warn-
ing function cannot prevent a collision.
The distance warning function issues a warn-
ing at speeds:
R of around 30 km/h or more, if, over several
seconds, the distance maintained to the
vehicle travelling in front is insufficient. The
· distance warning lamp then lights up
in the instrument cluster.
R of around 7 km/h or higher, if you very
quickly approach a vehicle in front. An
intermittent warning tone will then sound,
and the · distance warning lamp will
light up in the instrument cluster.
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XBrake immediately in order to increase the
distance from the vehicle in front.
or
XTake evasive action provided it is safe to do
so.
For the distance warning function to assist
you when driving, the function must be acti-
vated in the on-board computer and be opera-
tional ( Y page 218).
Due to the nature of the system, particularly
complicated but non-critical driving condi-
tions may also cause the system to display a
warning.
With the help of the radar sensor system, the
distance warning function can detect obsta-
cles that are in the path of your vehicle for an
extended period of time.
From a speed of around 70 km/h, the dis-
tance warning function can also react to sta-
tionary obstacles, such as stopped or parked
vehicles.
If you approach an obstacle and the distance
warning function detects a risk of a collision,
the system will alert you both visually and
acoustically.
In particular, the detection of obstacles can
be impaired in the case of:
R dirt on the sensors or the sensors are
obscured
R snow or heavy rain
R interference by other radar sources
R strong radar reflections, for example, in
multi-storey car parks
R a narrow vehicle travelling in front, e.g. a
motorcycle
R a vehicle travelling in front on a different
line
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensor checked at a qualified spe-
cialist workshop. This also applies to colli-
sions at slow speeds where there is no visible
damage to the front of the vehicle.
Adaptive Brake Assist
i Observe the "Important safety notes" sec-
tion for driving safety systems
( Y page 64).
GWARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions. In these cases, Adaptive Brake Assist
may not intervene. There is a risk of an acci-
dent.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
GWARNING
Adaptive Brake Assist does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R to stationary obstacles
R when cornering
As a result, Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
Due to the nature of the system, particularly
complicated but non-critical driving condi-
tions may also cause Brake Assist to inter-
vene.
Adaptive Brake Assist aids you in braking dur-
ing hazardous situations at speeds above
7 km/h and uses the radar sensor system to
evaluate the traffic situation.
With the help of a sensor system, adaptive
Brake Assist can detect obstacles that are in
the path of your vehicle for an extended
period of time.
Should you approach an obstacle and adap-
tive Brake Assist has detected a risk of colli-
sion, adaptive Brake Assist calculates the
braking force necessary to avoid a collision.
Should you apply the brakes forcefully, adap-
tive Brake Assist will automatically increase
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the braking force to a level suitable for the
traffic conditions.XKeep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if:
R you release the brake pedal
R there is no longer any danger of a collision
R no obstacle is detected in front of your
vehicle
Adaptive Brake Assist is then deactivated.
Vehicles with PRE-SAFE ®
: if adaptive Brake
Assist requires particularly high brake pres-
sure, preventive passenger protection meas-
ures (PRE-SAFE ®
) are deployed simultane-
ously.
Up to vehicle speeds of around 250 km/h,
adaptive Brake Assist is capable of reacting
to moving objects that have already been rec-
ognised as such at least once over the period
of observation. Adaptive Brake Assist does
not react to stationary obstacles.
If adaptive Brake Assist is not available due
to a malfunction in the radar sensor system,
the brake system remains available with full
brake boosting effect and BAS.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or the sensors are
obscured
R snow or heavy rain
R interference by other radar sources
R strong radar reflections, for example, in
multi-storey car parks
R a narrow vehicle travelling in front, e.g. a
motorcycle
R a vehicle travelling in front on a different
line
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensor checked at a qualified spe-
cialist workshop. This also applies to colli-
sions at slow speeds where there is no visible
damage to the front of the vehicle.
COLLISION PREVENTION ASSIST PLUS
General notes
COLLISION PREVENTION ASSIST PLUS is
only available on vehicles with DISTRONIC.
COLLISION PREVENTION ASSIST PLUS
extends the functionality of COLLISION PRE-
VENTION ASSIST with an automatic braking
function. COLLISION PREVENTION ASSIST
PLUS can help you to minimise the risk of a
front-end collision with a vehicle ahead or
reduce the effects of such a collision. If COL-
LISION PREVENTION ASSIST PLUS detects
that there is a risk of a collision, you will be
warned visually and acoustically. In critical
situations COLLISION PREVENTION ASSIST
PLUS also initiates automatic braking.
Function
XTo activate/deactivate: activate or deac-
tivate COLLISION PREVENTION ASSIST
PLUS in the on-board computer
( Y page 218).
If COLLISION PREVENTION ASSIST PLUS is
deactivated, the æ symbol appears in the
assistance graphics display.
If the driver's seat belt is fastened, COLLI-
SION PREVENTION ASSIST PLUS can brake
automatically within a speed range of
between 7 km/h and 200 km/h.
COLLISION PREVENTION ASSIST PLUS can
also react to stationary obstacles with auto-
matic braking within a speed range of
between 7 km/h and 30 km/h.
Vehicles with PRE-SAFE ®
: if the automatic
braking function of COLLISION PREVENTION
ASSIST PLUS intervenes powerfully, preven-
tive passenger protection measures (PRE-
SAFE ®
) are deployed simultaneously.
In particular, the detection of obstacles can
be impaired in the case of:
R dirt on the sensors or the sensors are
obscured
R snow or heavy rain
R interference by other radar sources
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Rstrong radar reflections, for example, in
multi-storey car parks
R a narrow vehicle travelling in front, e.g. a
motorcycle
R a vehicle travelling in front on a different
line
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensor checked at a qualified spe-
cialist workshop. This also applies to colli-
sions at slow speeds where there is no visible
damage to the front of the vehicle.
Adaptive brake lamps
Adaptive Brake Assist warns following traffic
in an emergency braking situation:
R by means of flashing brake lamps
R the hazard warning lamps are activated
If you brake sharply from a speed of more
than 50 km/h or if braking is assisted by BAS
or BAS PLUS, the brake lamps flash rapidly.
In this way, traffic travelling behind you is
warned in an even more noticeable manner.
If you brake sharply from a speed of more
than 70 km/h to a standstill, the hazard warn-
ing lamps are activated automatically. If the
brakes are applied again, the brake lamps
light up continuously. The hazard warning
lamps switch off automatically if you travel
faster than 10 km/h . You can also switch off
the hazard warning lamps using the hazard
warning button ( Y page 110).
ESP ®
(Electronic Stability Program)
General notes
i Observe the "Important safety notes" sec-
tion ( Y page 64).
ESP ®
monitors driving stability and traction,
i.e. power transmission between the tyres
and the road surface.
If ESP ®
detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilise the
vehicle. The engine output is also modified to
keep the vehicle on the desired course within
physical limits. ESP ®
assists the driver when
pulling away on wet or slippery roads. ESP ®
can also stabilise the vehicle during braking.
ETS (Electronic Traction System)
i Observe the "Important safety notes" sec-
tion ( Y page 64).
ETS traction control is part of ESP ®
.
ETS brakes the drive wheels individually if
they spin. This enables you to pull away and
accelerate on slippery surfaces, for example
if the road surface is slippery on one side. In
addition, more drive torque is transferred to
the wheel or wheels with traction.
ETS remains active when you deactivate
ESP ®
.
Important safety notes
GWARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilise the vehicle. In addition, other driving
safety systems are switched off. This increa-
ses the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
! When testing the electric parking brake
on a braking dynamometer, switch off the
ignition. Application of the brakes by
ESP ®
may otherwise destroy the brake sys-
tem.
When towing your vehicle with the front axle
raised, observe the notes on
ESP ®
(Y page 310).
ESP ®
is deactivated if the å ESP®
OFF
warning lamp in the instrument cluster lights
up continuously when the engine is running.
If the ÷ ESP®
warning lamp and the
å ESP®
OFF warning lamp are lit contin-
uously, ESP ®
is not available due to a mal-
function.
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Observe the information on warning lamps
( Y page 258) and display messages which
may be shown in the instrument cluster
( Y page 227).
i Only use wheels with the recommended
tyre sizes. Only then will ESP ®
function
properly.
Characteristics of ESP ®
General notes
If the ÷ ESP warning lamp goes out before
beginning the journey, ESP ®
is automatically
active.
If ESP ®
intervenes, the ÷ ESP®
warning
lamp flashes in the instrument cluster.
If ESP ®
intervenes:
XDo not deactivate ESP ®
under any circum-
stances.XWhen pulling away, only depress the accel-
erator pedal as far as is necessary.XAdapt your driving style to suit the prevail-
ing road and weather conditions.
ECO start/stop function
The ECO start/stop function switches the
engine off automatically if the vehicle stops
moving. When pulling away again, the engine
starts automatically. ESP ®
remains in its pre-
viously selected status. Example: if ESP®
was deactivated before the engine was
switched off, ESP ®
remains deactivated when
the engine is switched on again.
Deactivating/activating ESP ®
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y page 64).
You can select between the following states
of ESP ®
:
R ESP ®
is activated.
R ESP ®
is deactivated.
GWARNING
If you deactivate ESP ®
, ESP ®
no longer sta-
bilises the vehicle. There is an increased risk
of skidding and an accident.
Only deactivate ESP ®
in the situations descri-
bed in the following.
It may be best to deactivate ESP ®
in the fol-
lowing situations:
R when using snow chains
R in deep snow
R on sand or gravel
i Activate ESP ®
as soon as the situations
described above no longer apply. ESP ®
will
otherwise not be able to stabilise the vehi-
cle if the vehicle starts to skid or a wheel
starts to spin.
Deactivating/activating ESP ®
You can deactivate or activate ESP ®
via the
on-board computer.
XTo deactivate: (Y page 218).
The å ESP®
OFF warning lamp in the
instrument cluster lights up.XTo activate: (Y page 218).
The å ESP®
OFF warning lamp in the
instrument cluster goes out.
Characteristics when ESP ®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ ESP®
warning lamp in
the instrument cluster flashes. In such situa-
tions, ESP ®
will not stabilise the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R engine torque is no longer limited and the
drive wheels are able to spin.
The spinning of the wheels results in a cut-
ting action for better traction on loose sur-
faces.
R ETS is still active.
R ESP ®
still provides support when you
brake.
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ESP®
trailer stabilisation
General notes
If your vehicle/trailer combination begins to
swerve, ESP ®
assists you in this situation.
ESP ®
slows the vehicle down by braking and
limiting the engine output until the vehicle/
trailer combination has stabilised.
Important safety notes
GWARNING
If road and weather conditions are poor,
trailer stabilisation will not be able to prevent
the vehicle/trailer combination from swerv-
ing. Trailers with a high centre of gravity can
tip over before ESP ®
can detect this. There is
a risk of an accident.
Always adapt your driving style to the prevail-
ing road and weather conditions.
If your vehicle/trailer combination begins to
lurch, you can only stabilise the vehicle/
trailer combination by depressing the brake
firmly.
ESP ®
trailer stabilisation is active above
speeds of about 65 km/h.
ESP ®
trailer stabilisation does not work if
ESP ®
is deactivated or disabled because of a
malfunction.
EBD (electronic brake force distribu-
tion)
General notes
EBD monitors and controls the brake pres-
sure on the rear wheels to improve driving
stability while braking.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems
( Y page 64).
GWARNING
If EBD has malfunctioned, the rear wheels can
still lock, e.g. under full braking. This increa-
ses the risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have
the brake system checked at a qualified spe-
cialist workshop.
Observe information regarding indicator and
warning lamps ( Y page 256) as well as dis-
play messages ( Y page 229).
ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In addi-
tion to the braking function, ADAPTIVE BRAKE
also has the HOLD function (Y page 181) and
hill start assist ( Y page 147). For further
information, see Driving tips ( Y page 166).
STEER CONTROL
General notes
STEER CONTROL helps you by transmitting a
noticeable steering force to the steering
wheel in the direction required for vehicle
stabilisation.
This steering support is provided in particular
if:
R both right wheels or both left wheels are on
a wet or slippery road surface when you
brake.
R the vehicle starts to skid.
Important safety notes
If there is an ESP ®
malfunction, you will not
receive any steering support from STEER
CONTROL. Power steering will, however, con-
tinue to function.
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