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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 vehicle 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.
ABS works from a speed of about 8 km/h,
regardless of road-surface conditions. ABS
works on slippery surfaces, even when you only
brake gently.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 61). G
WARNING
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, includ-
ing driving safety systems, will also become
inoperative. Observe the information on the ABS warning lamp (Y page 249) and display mes-
sages which may be shown in the instrument
cluster (Y page 223).
Brakes X
If ABS intervenes: continue to depress the
brake pedal with force until the braking sit-
uation is over.
X To 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 indication
of hazardous road conditions; this serves as a
reminder to take extra care while driving. BAS (Brake Assist)
General notes BAS operates in emergency braking situations.
If you depress the brake pedal quickly, BAS
automatically boosts the braking force, thus
shortening the stopping distance.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 61). G
WARNING
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.
Brakes X
Keep 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. BAS PLUS (Brake Assist PLUS) with
Cross-Traffic Assist
General notes BAS PLUS can help you to minimise the risk of a
collision with a vehicle or a pedestrian and
reduce the effects of such a collision. If BAS
PLUS detects a danger of collision, you are
assisted when braking.
i Pay attention to the important safety notes
in the "Driving safety systems" section
(Y page 61).
BAS PLUS is only available on vehicles with the
Driving Assistance package.
For BAS PLUS to assist you when driving, the
radar sensor system and the camera system
must be operational. 62
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With the help of a sensor system and a camera
system, BAS PLUS can detect obstacles:
R that are in the path of your vehicle for an
extended period of time
R that cross the path of your vehicle
In addition, pedestrians in the path of your vehi-
cle can be detected.
BAS PLUS detects pedestrians using typical
characteristics such as the body contours and
posture of a person standing upright.
If the radar sensor system or the camera system is malfunctioning, BAS PLUS functions are
restricted or no longer available. The brake sys-
tem is still available with complete brake boost- ing effect and BAS.
i Observe the restrictions described in the
"Important safety notes" section
(Y page 63).
Important safety notes G
WARNING
BAS PLUS cannot always clearly identify
objects and complex traffic situations.
In such cases, BAS PLUS may:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake. Terminate the
intervention in a non-critical driving situation. G
WARNING
BAS PLUS cannot always clearly identify peo- ple, this is especially the case if they are mov-
ing. BAS PLUS cannot intervene in these
cases. There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. G
WARNING
BAS PLUS does not react:
R to small people, e.g. children
R to animals
R to oncoming vehicles
R when cornering As a result, BAS PLUS may not intervene in all
critical situations. There is a risk of an acci-
dent.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
In the event of snowfall or heavy rain, detection
can be impaired.
Detection by the radar sensor system is also
impaired in the event of:
R dirt on the sensors or obscured sensors
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
R vehicles quickly moving into the radar sensor
system detection range
Detection by the camera system is also impaired
in the event of:
R dirt on the camera or if the camera is covered
R glare on the camera system, e.g. from the sun
being low in the sky
R darkness
R if:
- pedestrians move quickly, e.g. into the path
of the vehicle
- the camera system no longer detects a
pedestrian as a person due to special cloth- ing or other objects
- a pedestrian is concealed by other objects
- the typical outline of a person is not distin-
guishable from the background
Following damage to the front end of the vehicle, have the radar sensor settings and operation
checked at a qualified specialist workshop. This also applies to collisions at slow speeds where
there is no visible damage to the front of the
vehicle.
Following damage to the windscreen, have the
configuration and operation of the camera sys-
tem checked at a qualified specialist workshop. Driving safety systems
63Safety Z
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Function
To avoid a collision, BAS PLUS calculates the
brake force necessary if:
R you approach an obstacle and
R BAS PLUS has detected a risk of a collision
When driving at a speed under 30 km/h: if
you depress the brake pedal, BAS PLUS is acti-
vated. Braking assistance from BAS PLUS is car-
ried out at the last possible moment.
When driving at a speed above 30 km/h: if
you depress the brake pedal sharply, BAS PLUS automatically increases the brake pressure to adegree suited to the traffic situation.
BAS PLUS provides braking assistance in haz-
ardous situations with vehicles in front within a
speed range between 7 km/h and 250 km/h.
Up to a speed of approximately 70 km/h, BAS
PLUS may react to:
R stationary objects in the path of your vehicle,
e.g. stopped or parked vehicles
R pedestrians in the path of your vehicle
R obstacles crossing your path, which move in
the detection range of the sensors and are
detected
i If BAS PLUS demands particularly high brak-
ing force, preventative passenger protection
measures (PRE-SAFE ®
) are activated simulta-
neously.
X Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
BAS PLUS is deactivated and the brakes func-
tion as usual, if:
R you release the brake pedal
R there is no longer a risk of collision
R no obstacle is detected in front of your vehicle
R you depress the accelerator pedal
R you activate kickdown COLLISION PREVENTION ASSIST
PLUS
General notes i
Observe the "Important safety notes" sec-
tion (Y page 61).
COLLISION PREVENTION ASSIST PLUS consists of a distance warning function with an autono- mous braking function and Adaptive Brake
Assist.
COLLISION PREVENTION ASSIST PLUS can help
you to minimise the risk of a collision with the
vehicle in front or reduce the effects of such a
collision.
If COLLISION PREVENTION ASSIST PLUS
detects that there is a risk of a collision, you will
be warned visually and acoustically. If you do not react to the visual and audible collision warning,
autonomous braking can be initiated in critical
situations. If you apply the brake yourself in a
critical situation, the COLLISION PREVENTION
ASSIST PLUS Adaptive Brake Assist assists you.
Important safety notes In particular, the detection of obstacles can be
impaired in the case of:
R dirt on the sensors or obscured sensors
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
R new vehicles or after a service on the COLLI-
SION PREVENTION ASSIST PLUS system
Please observe the information in the section on running-in the vehicle (Y page 131).
Following damage to the front end of the vehicle, have the configuration and operation of the
radar sensor checked at a qualified specialist
workshop. This also applies to collisions at slow speeds where there is no visible damage to thefront of the vehicle.
Activating/deactivating The COLLISION PREVENTION ASSIST PLUS is
automatically active after switching on the igni-
tion.
You can activate or deactivate COLLISION PRE-
VENTION ASSIST PLUS in the on-board com-
puter (Y page 214). When deactivated, the dis-
tance warning function and the autonomous
braking function are also deactivated.
If COLLISION PREVENTION ASSIST PLUS is
deactivated, the æsymbol appears in the
assistance graphics display. 64
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Distance warning function
General notes
The distance warning function can help you to
minimise the risk of a collision with the vehicle in front or reduce the effects of such a collision. If
the distance warning function detects that there
is a risk of a collision, you will be warned visually and acoustically.
Important safety notes i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 61).G
WARNING
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. G
WARNING
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
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation; do not rely on the distance warning
function alone.
Function The distance warning function issues a warning at speeds:
R of approximately 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 approximately 7 km/h or more, if you rap-
idly approach a vehicle in front. An intermit-
tent warning tone will then sound and the
· distance warning lamp will light up in the
instrument cluster.
X Brake immediately in order to increase the
distance from the vehicle in front.
or
X Take evasive action provided it is safe to do
so.
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause the system to display a warning.
With the help of the radar sensor system, the
distance warning function can detect obstacles
that are in the path of your vehicle for an exten-
ded period of time.
Up to a speed of approximately 70 km/h, the
distance warning function can also react to sta-
tionary obstacles, such as stopped or parked
vehicles.
Autonomous braking function If the driver does not react to the distance warn-
ing signal in a critical situation, COLLISION PRE- VENTION ASSIST PLUS can assist with the
autonomous braking function.
The autonomous braking function:
R gives the driver more time to react to critical
driving situations
R can help the driver to avoid an accident or
R reduces the effects of an accident
The autonomous braking function is available in
the following speed ranges:
R from 7 km/h to approximately 105 km/h for
moving objects
R from 7 km/h to approximately 50 km/h for
stationary objects
Due to the nature of the system, complicated
but non-critical driving conditions may also
cause the autonomous braking function to inter- vene.
If the autonomous braking function demands
particularly high braking force, preventative
passenger protection measures (PRE-SAFE ®
)
are activated simultaneously. Driving safety syste
ms
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Adaptive Brake Assist
General notes
i Observe the "Important safety notes" sec-
tion (Y page 61).
With the help of Adaptive Brake Assist, the dis-
tance warning signal can detect obstacles that
are in the path of your vehicle for an extended
period of time.
If Adaptive Brake Assist detects a risk of a col-
lision with the vehicle in front, it calculates the
braking force necessary to avoid a collision. If
you apply the brakes forcefully, Adaptive Brake
Assist will automatically increase the braking
force to a level suitable for the traffic conditions.
Adaptive Brake Assist provides braking assis-
tance in hazardous situations at speeds above
7 km/h. It uses radar sensor technology to
assess the traffic situation.
Up to a speed of approximately 250 km/h,
Adaptive Brake Assist is capable of reacting to
moving objects that have already been detected
as such at least once over the period of obser-
vation.
Up to a speed of approximately 70 km/h, Adap-
tive Brake Assist reacts to stationary obstacles.
If Adaptive Brake Assist demands a particularly
high braking force, preventative passenger pro-
tection measures (PRE-SAFE ®
) are activated
simultaneously (Y page 46).
X Keep 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.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 61).G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions. In such cases, Adaptive Brake Assist can:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake. Terminate the
intervention in a non-critical driving situation. G
WARNING
Adaptive Brake Assist does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
As a result, the 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 conditions
may also cause Brake Assist to intervene.
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. Adaptive brake lights
i Observe the "Important safety notes" sec-
tion (Y page 61).
The adaptive brake lights warn following traffic
in an emergency braking situation:
R by 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 warning
lamps are activated automatically. If the brakes are applied again, the brake lamps light up con-
tinuously. The hazard warning lamps switch off
automatically if you travel faster than 10 km/h. 66
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You can also switch off the hazard warning
lamps using the hazard warning button
(Y page 108). ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 61).
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 vehi- cle 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/4ETS (Electronic Traction System) ETS traction control is part of ESP
®
. On vehicles
with 4MATIC, 4ETS is a component of ESP ®
.
Traction control brakes the drive wheels indi-
vidually 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 transfer-
red to the wheel or wheels with traction.
Traction control remains active if you deactivate ESP ®
.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 61). G
WARNING
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.
! Vehicles with 4MATIC: function or perform-
ance tests may only be carried out on a 2-axle dynamometer. Before operating the vehicle on such a dynamometer, please consult a
qualified specialist workshop. You could oth-
erwise damage the drive train or the brake
system.
Vehicles without 4MATIC: when towing your
vehicle with the rear axle raised, observe the
notes on ESP ®
(Y page 309).
If the å ESP®
OFF warning lamp lights up
continuously, then ESP ®
is deactivated.
If the ÷ ESP®
warning lamp and the å
ESP ®
OFF warning lamp are lit continuously,
ESP ®
is not available due to a malfunction.
Observe the information on warning lamps
(Y page 249) and display messages which may
be shown in the instrument cluster
(Y page 223).
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:
X Do not deactivate ESP ®
under any circum-
stances.
X When pulling away, only depress the acceler-
ator pedal as far as is necessary.
X Adapt your driving style to suit the prevailing
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 previ-
ously selected status. Example:if ESP®
was
deactivated before the engine was switched off,
ESP ®
remains deactivated when the engine is
switched on again. Driving safety systems
67Safety Z
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Deactivating/activating ESP
®Important safety notes
You can select between the following statuses
of ESP ®
:
R ESP ®
is activated
R ESP ®
is deactivated. G
WARNING
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 follow-
ing 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 vehicle
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 (Y page 214).
ESP ®
deactivated:
The å ESP®
OFF warning lamp in the instru-
ment cluster lights up.
ESP ®
activated:
The å ESP®
OFF warning lamp in the instru-
ment 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 situations,
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 cutting action for better traction on loose surfaces. R
Traction control is still activated
R COLLISION PREVENTION ASSIST is no longer
available; nor is it activated if you brake firmly
with assistance from ESP ®
R PRE-SAFE ®
is no longer available; it is also not
activated if you brake firmly with assistance
from ESP ®
R PRE-SAFE ®
Brake is no longer available; it is
also not activated if you brake firmly with
assistance from ESP ®
R ESP ®
still provides support when you brake
firmly
ESP ®
trailer stabilisation General notes
If your vehicle/trailer combination begins to
lurch, ESP ®
assists you in this situation. ESP ®
slows the vehicle down by braking and limiting
the engine output until the vehicle/trailer com- bination has stabilised.
Important safety notes G
WARNING
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 approximately 65 km/h.
ESP ®
trailer stabilisation does not work if ESP ®
is deactivated or disabled because of a malfunc- tion. 68
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EBD (electronic brake force distribu-
tion)
General notes EBD monitors and controls the brake pressure
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 61).G
WARNING
If EBD is malfunctioning, the rear wheels can
lock, e.g. under full braking. This increases 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 249) as well as display
messages (Y page 224). ADAPTIVE BRAKE
i Observe the "Important safety notes" sec-
tion (Y page 61).
ADAPTIVE BRAKE enhances braking safety and
offers increased braking comfort. In addition to
the braking function, ADAPTIVE BRAKE also has the HOLD function (Y page 170) and hill start
assist (Y page 135). PRE-SAFE
®
Brake
General notes PRE-SAFE
®
Brake can help you to minimise the
risk of a collision with a vehicle ahead or a
pedestrian, and reduce the effects of such a
collision. If PRE-SAFE ®
Brake has detected a risk
of a collision, you will be warned visually and
acoustically as well as by automatic braking.
i Pay attention to the important safety notes
in the "Driving safety systems" section
(Y page 61). PRE
‑SAFE ®
Brake is only available in vehicles
with the Driving Assistance Plus package.
For PRE-SAFE ®
Brake to assist you when driving,
the radar sensor system and the camera system must be switched on and operational.
With the help of the radar sensor system and the
camera system, PRE-SAFE ®
Brake can detect
obstacles that are in front of your vehicle for an extended period of time.
In addition, pedestrians in the path of your vehi-
cle can be detected.
PRE-SAFE ®
Brake detects pedestrians using
typical characteristics such as the body con-
tours and posture of a person standing upright.
i Observe the restrictions described in the
"Important safety notes" section
(Y page 69).
Important safety notes G
WARNING
PRE-SAFE ®
Brake will initially brake your vehi-
cle by a partial application of the brakes if a
danger of collision is detected. There may be
a collision unless you brake yourself. Even
after subsequent full application of the brakes
a collision cannot always be avoided, partic-
ularly when approaching at too high a speed.
There is a risk of an accident.
Always apply the brakes yourself and try to
take evasive action, provided it is safe to do
so.
In the event of a partial application of the brakes, the vehicle is braked with up to 50% of the full
braking pressure. G
WARNING
PRE-SAFE ®
Brake cannot always clearly iden-
tify objects and complex traffic conditions.
In these cases, PRE-SAFE ®
Brake may:
R give an unnecessary warning and then
brake the vehicle
R neither give a warning nor intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and be ready to brake, especially if Driving safety systems
69Safety
Z