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In wintry driving conditions, alwaysu
se
winter tyres (M+S tyres) and if necessary,
snow chains. Only in this way willt he driv-
ing safety systems describe dinthis section
work as effectively as possible. ABS (Anti-loc
kBraking System)
Important safety notes i
Observe the "Important safety notes" sec-
tio n(Ypage 61).
ABS regulate sbrake pressure in such away
tha tthe wheels do not lock when you brake.
This allowsy ou to continue steering the vehi-
cle when braking.
ABS works from aspeed of about 8km/h
upwards, regardless of road-surface condi-
tions. ABS works on slippery surfaces, even
when you only brake gently. G
WARNING
If ABS is faulty, the wheels could lock when
braking. This limits the steerability of the vehi-
cle when braking and the braking distance
may increase.
If ABS is deactivated due to amalfunction,
then BAS and ESP are also deactivated. There
is an increased risk of your vehicle skidding in
certain situations.
You should always adapt your driving style to
suit the prevailing road and weather condi-
tions.
Braking If ABS intervenes when braking, you will feel
ap ulsing in the brake pedal.
X If ABS intervenes: continue to depress the
brake pedal with force until the braking sit-
uation is over.
X To make afull brake application:
depress the brake pedal with full force.
The pulsating brake pedal can be an indica-
tion of hazardous road conditionsa nd func-tions as
areminder to take extrac are while
driving. G
WARNING
Do not depress the brake pedal several times
in quick succession (pumping). Pumping the
brake pedal reduces the braking effect.Y ou
might otherwise not be able to stop the vehi-
cle in time and could cause an accident.
Depress the brake pedal firmly and smoothly. BAS (Brake Assist)
i Observe the "Important safety notes" sec-
tion (Y page 61).
BAS operates in emergenc ybraking situa-
tions. If you depress the brake pedal quickly,
BAS automatically boosts the braking force,
thus shortening the stopping distance.
X Keep the brake pedal firmly depressed until
the emergenc ybraking situation is over.
ABS prevent sthe wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. G
WARNING
If BAS has malfunctioned, the braking system
remains available with full brake boosting
effect .However, braking force is not auto-
matically increased in emergenc ybraking sit-
uations and the stopping distance may
increase. BAS PLUS (Brake Assist System
PLUS)
BAS PLUS is only available on vehicles with
DISTRONIC PLUS.
i Observe the "Important safety notes" sec-
tion (Y page 61).
BAS PLUS provides braking assistance in haz-
ardous situations at speeds of over
30 km/ha nd uses rada rsensor technology
to assess the traffic situation. 62
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ysystemsSafety
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With the help of the radar sensor system, BAS
PLUS can detect obstacles that are in the
path of your vehicle for an extended period of
time.
At speeds up to approximately 70 km/h, BAS
PLUS may also detect stationar yobstacles,
for example, stopped or parked vehicles.
Should yo uapproach an obstacl eand BAS
PLUS ha sdetected ariskofc ollision, BAS
PLUS calculates the braking force necessary
to avoid arear-en dcollision. Should you apply
the brakes forcefully,B AS PLUS can auto-
matically increase the braking force to alevel
suitable for the traffic conditions.
If BAS PLUS demands particularly high brak-
ing force, preventative passenger protection
measures (PRE-SAFE ®
)a re activated simul-
taneously.
X Keep the brake pedal depressed until the
emergenc ybraking situation is over.
ABS prevent sthe wheels from locking.
The brakes will work normally again if:
R you release the brake pedal.
R there is no longer any danger of arear-end
collision.
R no obstacle is detected in front of your
vehicle.
BAS PLUS is then deactivated.
The radar sensor system is switched off auto-
matically in the vicinit yofradio telescope
facilities (Y page 345).
Vehicles without COMAND and anavigation
system and vehicles for Australia: the radar
sensor system and on-board computer must
be switched off in the vicinit yofradio tele-
scope facilities (Y page 229).
For BAS PLUS to assist you when driving, the
radar sensor system must be switched on and
operational; see "Radar sensor system" in the
index. G
WARNING
BAS PLUS cannot alwaysc learly identify
object sand complex traffic situations. BAS
PLUS cannot intervene in these cases. There is
arisk of an accident .Always pay
careful attention to the traffic situation and be
ready to brake.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or anything else cover-
ing the sensors
R sno worh eavy rain
R interference by other radar sources
R the possibilit yofstrong radar reflections,
for example in multi-storey car parks
R an arrow vehicle travellin ginfront,e.g. a
motorbike
R av ehicle travellin ginfront on adifferent
line G
WARNING
BA SP LUS does not react:
R to people or animals
R to oncomin gvehicles
R to crossin gtraffic
R when cornering
As aresult ,BAS PLUS may not intervene in
critical situations .There is arisk of an acci-
dent. Always pay careful attention to the traf-
fic situation and be ready to brake.
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensors checked at aqualified spe-
cialist workshop. This also applies to colli-
sions at slow speeds where there is no visible
damage to the front of the vehicle.
If BAS PLUS is not available due to amalfunc-
tion in the radar sensor system, the brake
system remains available with full brake
boosting effect and BAS. Adaptive brake lamps
i Adaptive brake lamps are only available in
certain countries.
If you brake sharply from aspeed of more
than 50 km/h or if braking is assisted by BAS Driving safety systems
63Safety Z
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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 aspeed of more
than 70 km/htoa 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 automaticallyify ou travel
faster than 10 km/h .You can also switch off
the hazard warning lamps using the hazard
warning switch button (Y page 117).ESP
®
(Electronic Stability Program)
Important safety notes i
See the "Important safety notes" section
(Y page 61).
If ESP ®
detect sthat the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilise the
vehicle. If necessary, 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 slip-
pery roads. ESP ®
can also stabilise the vehi-
cle during braking.
If ESP ®
intervenes, the ÷ESP®
warning
lamp flashes in the instrument cluster. G
WARNING
If the ÷ warning lamp in the instrument
cluster flashes, proceed as follows:
R do not deactivate ESP ®
under any circum-
stances.
R only depress the accelerator pedal as far as
necessary when pulling away.
R adapt your driving style to suit the prevail-
ing road and weather conditions.
Otherwise, the vehicle could go into askid.
ESP ®
cannot reduce the risk of an accident if
you drive too fast. ESP ®
cannot override the
laws of physics. !
Switch the ignition off when:
R the parking brake is being tested using a
dynamometer
R the vehicle is being towed with the front/
rear axle raised
Application of the brakes by ESP ®
may oth-
erwise destroy the brake system.
i Only use wheels with the recommended
tyre sizes. Only then will ESP ®
function
properly.
ETS (Electronic Traction Support) Traction control is part of ESP
®
.
Traction control brakes the drive wheels indi-
viduall yifthey spin. This enables you to pull
away and accelerate on slippery surfaces, for
example if the road surface is slippery on one
side.
Traction control remains active if you deacti-
vate ESP ®
. G
WARNING
Traction control cannot reduce the risk of an
accident if you drive too fast. Traction control
cannot override the laws of physics.
Deactivating/activating ESP ® i
Observe the "Important safety notes" sec-
tion (Y page 61).
ESP ®
is activated automatically when the
engine is started.
i Vehicles with ECO start/stop function:
the ECO start/stop function switches the
engine off automatically when the vehicle
comes to astop. The engine startsa uto-
matically when the driver wants to pull
away again. ESP ®
remains in its previously
selected status. Example: if ESP ®
was
deactivated before the engine was
switched off, ESP ®
remains deactivated
when the engine is switched on again. 64
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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 G
WARNING
Activate ESP ®
as soon as the situations
describe dabove no longer apply. ESP ®
will
otherwis enot be abletos tabilise the vehicle
if the vehicle starts to skid or awhee lstarts
to spin.
When you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R the engine's torque is no longer limited and
the drive wheels can spin. The spinning of
the wheels results in acutting action, which
provide sbetter grip.
R traction control is still activated.
R ESP ®
still provide ssupport when you
brake.
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 ®
willn ot stabilise the vehicle.
X To deactivate: (Ypage 223).
The å ESP®
OFF warning lamp in the
instrument cluster lights up. G
WARNING
ESP ®
is deactivated if the åwarning lamp
in the instrument cluster lights up continu-
ouslyw hen the engine is running.
If the ÷ warning lamp and åwarning
lamp are lit continuously, ESP ®
is not availa-
ble due to amalfunction.
There is an increased risk of yourv ehicle skid-
ding in certain situations.
You should alway sadapt your driving style to
suit the prevailing road and weather condi-
tions. X
To activate:(Y page 223).
The å ESP®
OFF warning lamp in the
instrument cluster goes out.
ESP ®
trailer stabilisation If your vehicle with trailer (vehicle/trailer
combination) begins to lurch, you can only
stabilise the vehicle/trailer combination by
depressing the brake firmly.
In this situation ,ESP ®
assists you and can
detec tifthe vehicle/trailer combination
begins to lurch. ESP ®
slows the vehicle down
by braking and limiting the engine output until
the vehicle/trailer combination has stabi-
lised.
Trailer stabilisation is active above speeds of
about 65 km/h. G
WARNING
If road and weather conditions are poor,
trailer stabilisation will not be able to prevent
the trailer from swerving and will thus be
unable to reduce the risk of an accident. Trail-
ers with ahigh centre of gravity can tip over
before ESP ®
can detect this.
Trailer stabilisation does not work if ESP ®
is
deactivated or disabled because of amal-
function. EBD (electronic brake force distribu-
tion)
i Observe the "Important safety notes" sec-
tion (Y page 61).
EBD monitors and controls the brake pres-
sure on the rear wheels to improve driving
stability while braking. G
WARNING
If EBD has malfunctioned, the braking system
remains available with full brake boosting
effect.H owever, the rear wheels can still lock,
e.g. under full braking. This could cause you
to lose control of your vehicle and cause an
accident .You should therefor eadapt your Driving safety systems
65Safety
Z
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driving style to the differen
thandling charac-
teristics.
X Observ ethe note sonw arning and indicator
lamps (Y page 257) as well as display mes-
sages ( Ypage 234). ADAPTIV
EBRAKE
ADAPTIV EBRAKE enhances braking safety
and offers increased braking comfort. In addi-
tio ntot he brakin gfunction, ADAPTIVE BRAKE
alsoh as the HOLD function (Y page184) and
hills tart assist (Y page149). For further
information, see Driving tips (Y page167). PRE-SAFE
®
Brake
PRE-SAFE ®
Brake is only available in vehicles
with DISTRONIC PLUS.
i Observe the "Important safety notes" sec-
tion (Y page61).
PRE-SAFE ®
Brake can help you to minimise
the risk of afrontal collision with avehicle
ahead or reduce the effects of such acolli-
sion. If PRE-SAFE ®
Brake has detected arisk
of collision, you willbew arned visuallya nd
acoustically as wellasbya utomatic braking.
PRE-SAFE ®
Brake cannot prevent acollision
without youri ntervention.
Thi sfun ctio nwill issue awarnin gats peeds of
aroun d30k m/horm orei f:
R for aperiod of several seconds ,the dis-
tance to the vehicle in front is too shor tfor
the speed at which you are travelling. The
· distance warning lamp then lights up
in the instrument cluster.
R you are rapidly approaching the vehicle in
front.Ani ntermittent warning tonew ill
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.
If the driver and passengers have fastened
their seat belts, PRE-SAFE ®
Brake can also
can also perform the following at speeds of
above approximately 30 km/h:
R brake the vehicle automatically from a
speed of up to approximately 200 km/h
R trigger preventative passenger protection
measures (PRE-SAFE ®
)( Ypage 45)
Due to the nature of the system, particularly
complicated driving conditions may cause
unnecessary warnings or the unnecessary
intervention of PRE-SAFE ®
Brake. To end this,
you can either depress the accelerator pedal
further, activate kickdown or release the
brake pedal.
The braking action of PRE-SAFE ®
Brake is
ended automatically if:
R you drive slower than approximately
15 km/h.
R you manoeuvre to avoid the obstacle.
R there is no longer any danger of arear-end
collision.
R there is no longer an obstacle detected in
front of your vehicle.
With the help of the radar sensor system,
PRE-SAFE ®
Brake can detect obstacles that
are in front of your vehicle for an extended
period of time.
At speeds up to approximately 70 km/h,
PRE-SAFE ®
Brake may also detect stationary
obstacles, for example stopped or parked
vehicles.
If you approach an obstacle and PRE-SAFE ®
Brake detect sarisk of acollision, the system
will initially alert you both visually and acous-
tically. If you do not brake or take evasive
action, the system will warn you by automat-
ically braking the vehicle gently. If there is an
increased risk of collision, preventative 66
Driving safety systemsSafety
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passenger protection measures (PRE-SAFE
®
)
are activated (Y page 45). If the risk of colli-
sion remains and you do not brake, tak eeva-
sive action or accelerate significantly, the
vehicle may perfor mautomatic emergency
braking .Automatic emergenc ybraking is not
performed until immediately prio rtoanacci-
dent that can no longer be avoided. G
WARNING
Even if PRE-SAFE ®
Brake slows the vehicle
before an imminent rear-end collision, the
system cannot avert acollision without the
intervention of the driver. There is arisk of an
accident .Brake according to the situation or
take evasive action. Delayed intervention by
the driver can lead to an accident. G
WARNING
PRE-SAFE ®
Brake cannot alwaysc learly iden-
tify object sand complex traffic conditions.
In these cases, PRE-SAFE ®
Brake may:
R give an unnecessary warning and then
brake the vehicle
R not give awarning or intervene
There is arisk of an accident .Always pay par-
ticular attention to the traffic situation and be
ready to brake, especially if PRE-SAFE ®
Brake
warns you. Terminat ethe intervention in a
non-critical drivin gsituation.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or anything else cover-
ing the sensors
R sno worh eavy rain
R interference by other radar sources
R the possibilit yofstrong radar reflections,
for example in multi-storey car parks
R an arrow vehicle travellin ginfront,e.g. a
motorbike
R av ehicle travellin ginfront on adifferent
line G
WARNING
PRE-SAFE ®
Brak edoes not react:
R to people or animals
R to oncomin gvehicles
R to crossin gtraffic
R when cornering
As aresult ,PRE-SAFE ®
Brak emay not give
warnings or intervene in critical situations.
There is arisk of an accident .Always pay
careful attention to the traffic situation and be
ready to brake.
In order to maintain the appropriate distance
to the vehicle in front and thus prevent acol-
lision ,you must apply the brakes yourself.
X To activate/deactivate: activate or deac-
tivate PRE-SAFE ®
Brak eint he on-board
computer (Y page 223).
The Ä symbol appears in the multifunc-
tion display as long as the HOL Dfunction
is no tactivated (Y page 184).
On vehicles wit hparking guidance, the
Ä symbol is displayed when Pis
engaged or you are driving faste rthan
35 km/h.
The radar sensor system is switched off auto-
matically in the vicinity of radio telescope
facilities (Y page 345).
Vehicles without COMAND and anavigation
system and vehicles for Australia: the radar
sensor system and on-board computer must
be switched off in the vicinity of radio tele-
scope facilities (Y page 229).
For PRE-SAFE ®
Brake to assist you when driv-
ing, the radar sensor system must be
switched on (Y page 229) and be opera-
tional.
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensors checked at aqualified spe-
cialist workshop. This also applies to colli-
sions at slow speeds where there is no visible
damage to the front of the vehicle. Driving safety systems
67Safety Z
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Anti-thef
tsystems Immobiliser
The immobiliser prevents your vehicl efrom
bein gstarted without th ecorrect key.
X To activat ewith the key: remove the key
from the ignition lock.
X To activate with KEYLESS-GO: switch the
ignition off and open the driver's door.
X To deactivate: switch on the ignition.
i The immobiliser is alway sdeactivated
when you start the engine. ATA (Anti-Theft Alarm system)
Av isual and audible alarm is triggere difthe
alarm system is prime dand you open:
R ad oor
R the vehicle with the emergency key ele-
ment
R the boot lid
R the bonnet
The alarm is not switched off ,even if you
clos ethe open door that has triggere dit, for
example. X
To prime: lock the vehicle with the key or
KEYLESS-GO.
Indicator lamp :flashes .The alarm sys-
tem is primed after approximately 15 sec-
onds.
X To deactivate: unlock the vehicle with the
key or KEYLESS-GO. X
To stop the alarm using the key: insert
the key into the ignition lock.
The alarm is switched off.
or
X Press the %or& button on the key.
The alarm is switched off.
X To stop the alarm using KEYLESS-GO:
grasp the outside door handle. The key
must be outside the vehicle.
The alarm is switched off.
or
X Press the Start/Stop button on the dash-
board. The key must be inside the vehicle.
The alarm is switched off. Tow-away protection
An audible and visual alarm is triggered if your
vehicle's angle of inclination is altered while
tow-away protection is primed. This occurs if
the vehicle is jacked up on one side, for exam-
ple.
X To prime: lock the vehicle with the key or
KEYLESS-GO.
Tow-away protection is primed after
approximately 30 seconds.
X To deactivate: unlock the vehicle with the
key or KEYLESS-GO.
Tow-away protection is deactivated auto-
matically.
To prevent afalse alarm, deactivate tow-away
protection manually if your vehicle:
R is being transported
R is being loaded onto aferry or car trans-
porter, for example
R is parked on amovable surface, e.g. in a
split-level garage
Deactivating:
X Remove the key from the ignition lock. 68
Anti-theft systemsSafety
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X
Press button :.
Indicator lamp ;lights up briefly.
X Lock the vehicle with the key or KEYLESS-
GO.
Tow-away protection is deactivated.
Tow-away protection remains deactivated
until:
R the vehicle is unlocked again.
R ad oor is opened and closed again.
R the vehicle is locked again. Interior motion sensor
If the interior motion sensor is primed, avis-
ual and audibl ealarm is triggered if move-
ment is detected in the vehicle interior while
the vehicle is locked. This occurs if someone
reaches into the vehicle interior, for example.
To activate:
X Make sure that:
R
the side windows are closed.
R the panorama sliding sunroof is closed
(Coupé).
This will prevent false alarms.
X Cabriolet: make sure that the roof is
closed.
X Lock the vehicle with the key or KEYLESS-
GO.
The interior motion sensor is primed after
approximately 30 seconds.
i Cabriolet: in some countries, the interior
motion sensor is primed even if the soft top
is open. The vehicle should only be parked with the soft top closed, however, to pre-
vent insect
sorfalling leaves, for example,
from causing false alarms.
To switch off:
X Unlock the vehicle with the key or KEY-
LESS-GO.
The interior motion sensor is deactivated
automatically.
To prevent afalse alarm, deactivat ethe inte-
rior motion sensor if you lock your vehicle
and:
R people or animals remain in the vehicle.
R the side windows remain open.
R the panorama sliding sunroof remains open
(Coupé).
Deactivating:
X Remove the key from the ignition lock. X
Press button :.
Indicator lamp ;flashes briefly.
X Lock the vehicle with the key or KEYLESS-
GO.
The interior motion sensor is deactivated.
The interior motion sensor remains deactiva-
ted until:
R the vehicle is unlocked again.
R ad oor is opened and closed again.
R the vehicle is locked again.
i UK only: Your vehicle is equipped with a
double lock function. The doors cannot be
opened from the inside if the vehicle has
been locked with the key (Y page 77).
Deactivate the interior motion sensor Anti-theft systems
69Safety Z