PRE-SAFE®takes the following measures
depending on the hazardous situation detected:
Rthe front seat belts are pre-tensioned.
Rif the vehicle skids, the side windows and the
sliding sunroof are closed.
Rvehicles with the memory function for the
front-passenger seat: the front-passenger
seat is adjusted if it is in an unfavorable posi-
tion.
If the hazardous situation passes without result-
ing in an accident, PRE-SAFE
®slackens the belt
pre-tensioning. All settings made by PRE-SAFE®
can then be reversed.
If the seat belt pre-tensioning is not reduced:
XMove the seat backrest or seat back slightly
when the vehicle is stationary.
The seat belt pre-tensioning is reduced and
the locking mechanism is released.
The seat-belt adjustment is an integral part of
the PRE-SAFE
®convenience function. You will
find information on the convenience function
under "Belt adjustment" (
Ypage 51).
PRE-SAFE®PLUS (anticipatory occu-
pant protection system PLUS)
Introduction
PRE-SAFE®PLUS is only available in vehicles
with the Driving Assistance package.
Using the radar sensor system, PRE-SAFE
®
PLUS is able to detect that a head-on or rear-end
collision is imminent. In certain hazardous sit-
uations, PRE-SAFE
®PLUS takes pre-emptive
measures to protect the vehicle occupants.
Important safety notes
The intervention of PRE-SAFE®PLUS cannot
prevent an imminent collision.
The driver is not warned about the intervention
of PRE-SAFE
®PLUS.
PRE-SAFE®PLUS does not intervene if the vehi-
cle is backing up.
When driving, or when parking or exiting a park-
ing space with assistance from Active Parking
Assist, PRE-SAFE
®PLUS will not apply the
brakes.
Function
PRE-SAFE®PLUS intervenes in certain situa-
tions if the radar sensor system detects an
imminent head-on or rear-end collision.
PRE-SAFE
®PLUS takes the following measures
depending on the hazardous situation detected:
Rif the radar sensor system detects that a
head-on collision is imminent, the seat belts
are pre-tensioned.
Rif the radar sensor system detects that a rear-
end collision is imminent:
-the brake pressure is increased if the driver
applies the brakes when the vehicle is sta- tionary.
-the seat belts are pre-tensioned.
The PRE-SAFE®PLUS braking application is can-
celed:
Rif the accelerator pedal is depressed when a
gear is engaged
Rif the risk of a collision passes or is no longer
detected
Rif DISTRONIC PLUS indicates an intention to
pull away
If the hazardous situation passes without result-
ing in an accident, the original settings are
restored.
Automatic measures after an acci-
dent
Immediately after an accident, the following
measures are implemented, depending on the
type and severity of the impact:
Rthe hazard warning lamps are activated
Rthe emergency lighting is activated
Rthe vehicle doors are unlocked
Rthe front side windows are lowered
Rvehicles with a memory function: the electri-
cally adjustable steering wheel is raised
Rthe engine is switched off and the fuel supply
is cut off
Rvehicles with mbrace: automatic emergency
call
Rvehicles with the hybrid drive system: the
hybrid system and the high-voltage electrical
system are deactivated
Occupant safety61
Safety
Z
Braking
XKeep the brake pedal firmly depressed 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 System
PLUS) with Cross-Traffic Assist
General information
BAS PLUS can help you to minimize 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.
iPay attention to the important safety notes
in the "Driving safety systems" section
(
Ypage 68).
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.
With the help of a sensor system and a camera
system, BAS PLUS can detect obstacles:
Rthat are in the path of your vehicle for an
extended period of time
Rthat cross the path of your vehicle
In addition, pedestrians in the path of your vehi- cle can be detected.
BAS PLUS detects pedestrians by 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.
iObserve the restrictions described in the
"Important safety notes" sec-
tion“ (
Ypage 69).
Important safety notes
GWARNING
BAS PLUS cannot always clearly identify
objects and complex traffic situations.
In such cases, BAS PLUS may:
Rintervene unnecessarily
Rnot 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.
GWARNING
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.
GWARNING
BAS PLUS does not react:
Rto small people, e.g. children
Rto animals
Rto oncoming vehicles
Rwhen 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, the rec-
ognition can be impaired.
Recognition by the radar sensor system is also
impaired if:
Rthere is dirt on the sensors or anything else
covering the sensors
Rthere is interference by other radar sources
Rthere are strong radar reflections, for exam-
ple in parking garages
Ra narrow vehicle is traveling in front, e.g. a
motorbike
Driving safety systems69
Safety
Z
Ra vehicle is traveling in front on a different line
Rvehicles quickly move into the radar sensor
system detection range
Recognition by the camera system is also
impaired in the event of:
Rdirt on the camera or if the camera is covered
Rglare on the camera system, e.g. from the sun being low in the sky
Rdarkness
Ror if:
-pedestrians move quickly, e.g. into the path
of the vehicle
-the camera system no longer recognizes 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 configuration and operation of the
radar sensors 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 windshield, have the
configuration and operation of the camera sys-
tem checked at a qualified specialist workshop.
Function
To avoid a collision, BAS PLUS calculates the
brake force necessary if:
Ryou approach an obstacle, and
RBAS PLUS has detected a risk of collision
When driving at a speed under 20 mph
(30 km/h) : if you depress the brake pedal, BAS
PLUS is activated. The increase in brake pres-
sure will be carried out at the last possible
moment.
When driving at a speed above 20 mph
(30 km/h): if you depress the brake pedal
sharply, BAS PLUS automatically raises the
brake pressure to a value adapted to the traffic
situation.
BAS PLUS provides braking assistance in haz-
ardous situations with vehicles in front within a
speed range between 4 mph (7 km/h) and
155 mph (250km/ h). At speeds of up to approximately 44 mph
(70 km/h), BAS PLUS can react to:
Rstationary objects in the path of your vehicle,
e.g. stopped or parked vehicles
Rpedestrians in the path of your vehicle
Robstacles crossing your path, which move in
the detection range of the sensors and are
recognized by them
iIf BAS PLUS demands particularly high brak-
ing force, preventative passenger protection
measures (PRE-SAFE
®) are activated simulta-
neously (Ypage 60).
XKeep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the whee ls fro
m locking.
BAS PLUS is deactivated and the brakes func-
tion as usual again, if:
Ryou release the brake pedal.
Rthere is no longer a risk of collision.
Rno obstacle is detected in front of your vehi-
cle.
Ryou depress the accelerator pedal
Ryou activate kickdown.
COLLISION PREVENTION ASSIST
PLUS
General information
iObserve the "Important safety notes" sec-
tion (Ypage 68).
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 minimize the risk of a front-end collision
with a vehicle ahead 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.
70Driving safety systems
Safety
Important safety notes
In particular, thedetection of obstacles can be
impaired if:
Rthere is dirt on th esensor sor anythin gelse
covering th esensor s
Rthere is snow or heav yrain
Rthere is interferenc eby other radar source s
Rthere are strongradar reflections, for exam-
ple in parking garages
Ra narrow vehicl eis traveling in front, e.g. a
motorbike
Ra vehicl eis traveling in fron ton adifferen tlin e
Rthevehicl eis ne wor after aservic eon th e
COLLISION PREVENTION ASSIST PLU Ssys-
te m
Observ eth eimportant safet ynote sin th e
"Breaking-in notes" section (
Ypage 145).
Followin gdamag eto th efron ten dof th evehicle,
have th econfiguration and operation of th e
radar sensor checke dat aqualified specialist
workshop. This also applie sto collision sat slow
speeds wher ethere is no visible damag eto th e
fron tof th evehicle.
Switching on/off
The COLLISION PREVENTION ASSIST PLU Sis
automatically active after switching on th eigni-
tion .
You can activat eor deactivat eCOLLISION PRE -
VENTION ASSIST PLU Sin th eon-board com-
puter (
Ypage 247). When deactivated, th edis-
tance warning function and th eautonomous
braking function are also deactivated.
If COLLISION PREVENTION ASSIST PLU Sis
deactivated, th eæ symbol appear sin th e
assistanc egraphic sdisplay.
Distance warning function
Gene ral inform ation
The distanc ewarning function can help you to
minimiz eth eris kof afront-en dcollision wit h a
vehicl eahead or reduce th eeffects of suc h a
collision .If th edistanc ewarning function
detects that there is aris kof acollision ,you will
be warned visually and acoustically.
Important safety notes
iObserv eth e"Importan tsafet ynotes" sec -
tion for driving safet ysystems (Ypage 68).
GWARNIN G
The distanc ewarning function does no treact:
Rto people or animals
Rto oncomin gvehicles
Rto crossing traffic
Rwhen cornering
Thus ,th edistanc ewarning function canno t
provide awarning in all critical situations.
Ther eis aris kof an accident.
Always pay careful attention to th etraffic sit -
uation and be read yto brake.
GWARNIN G
The distanc ewarning function canno talways
clearly identify objects and comple xtraffic
situations.
In suc hcases, th edistanc ewarning function
may:
Rgiv ean unnecessary warning
Rno tgiv e a warning
Ther eis aris kof an accident.
Always pay careful attention to th etraffic sit -
uation and do no trel ysolely on th edistanc e
warning function .
Function
Starting ataspee dof approximately 4mph
(7 km/h), th edistanc ewarning function warn s
you if you rapidly approac h avehicl ein front. An
intermittent warning tone will then sound, and
th e· distanc ewarning lamp will ligh tup in
th einstrumen tcluster.
XBrake immediately in order to increas eth e
distanc efrom th evehicl ein front.
or
XTak eevasive action ,provide dit is saf eto do
so.
Due to th enature of th esystem, particularly
complicated but non-critical driving condition s
may also caus eth esystem to display awarning .
Wit hth ehelp of th eradar sensor system, th e
distanc ewarning function can detec tobstacles
Driving safety systems71
Safety
Z
that are in the path of your vehicle for an exten-
ded period of time.
Up to a speed of approximately 44 mph
(70 km/h), the distance warning function can
also react to stationary obstacles, such as stop-
ped 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:
Rgives the driver more time to react to critical
driving situations
Rcan help the driver to avoid an accident or
Rreduces the effects of an accident
Vehicles without DISTRONIC PLUS: the
autonomous braking function is available in the
following speed ranges:
R4 - 65 mph (7 - 105 km/h) for moving objects
R4 - 31 mph (7 - 50 km/h) for stationary
objects
Vehicles with DISTRONIC PLUS: the autono-
mous braking function is available in the follow-
ing speed ranges:
R4 - 124 mph (7 - 200 km/h) for moving
objects
R4 - 31 mph (7 - 50 km/h) for stationary
objects
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause the Autonomous Braking Func-
tion to intervene.
If the autonomous braking function requires a
particularly high braking force, preventative
passenger protection measures (PRE-SAFE
®)
are activated simultaneously (Ypage 60).
Adaptive Brake Assist
General information
iObserve the "Important safety notes" sec-
tion (Ypage 68).
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 colli-
sion 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
4 mph (7 km/h). It uses radar sensor technology
to assess the traffic situation.
Up to a speed of approximately 155 mph
(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 observation.
Up to a speed of approximately 44 mph
(70 km/h), adaptive Brake Assist reacts to sta-
tionary obstacles.
If Adaptive Brake Assist demands particularly
high braking force, preventative passenger pro-
tection measures (PRE-SAFE
®) are activated
si multaneously (Ypage 60).
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:
Ryou release the brake pedal.
Rthere is no longer any danger of a collision.
Rno obstacle is detected in front of your vehi-
cle.
Adaptive Brake Assist is then deactivated.
Important safety notes
iObserve the "Important safety notes" sec-
tion for driving safety systems (Ypage 68).
GWARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist can:
Rintervene unnecessarily
Rnot 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.
72Driving safet ysystem s
Safety
GWARNING
Adaptive Brake Assist does not react:
Rto people or animals
Rto oncoming vehicles
Rto crossing traffic
Rwhen 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.
ESP®(Electronic Stability Program)
General notes
iObserve the "Important safety notes" sec-
tion (Ypage 68).
ESP
®monitors driving stability and traction, i.e.
power transmission between the tires 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 stabilize 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 stabilize
the vehicle during braking.
ETS/4ETS (Electronic Traction System)
iObserve the "Important safety notes" sec-
tion (Ypage 68).
ETS traction control is part of ESP
®. On vehicles
with 4MATIC, 4ETS is part 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, even if you
deactivate ESP
®.
Important safety notes
iObserve the "Important safety notes" sec-
tion (Ypage 68).
GWARNING
If ESP
®is malfunctioning, ESP®is unable to
stabilize the vehicle. Additionally, further driv-
ing safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP
®checked at a
qualified specialist workshop.
When towing the vehicle with the rear axle
raised, observe the notes on ESP
®
(Ypage 355).
If the å ESP®OFF warning lamp lights up
continuously, ESP®is deactivated.
If the ÷ ESP®warning lamp lights up contin-
uously, ESP®is not available due to a malfunc-
tion.
Observe the information on warning lamps
(
Ypage 290) and display messages which may
be shown in the instrument cluster
(
Ypage 256).
Only use wheels with the recommended tire
sizes. Only then will ESP
®function properly.
Characteristics of ESP®
General information
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.
XOnly depress the accelerator pedal as far as
necessary when pulling away.
XAdapt your driving style to suit the prevailing
road and weather conditions.
Driving safety systems73
Safety
Z
PRE-SAFE®Brake
General information
PRE-SAFE®Brake can help you to minimize 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 collision, you will be warned visually and
acoustically as well as by automatic braking.
iPay attention to the important safety notes
in the "Driving safety systems" section
(
Ypage 68).
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 be 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.
iObserve the restrictions described in the
"Important safety notes" section
(
Ypage 77).
Important safety notes
GWARNING
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.
GWARNING
PRE-SAFE
®Brake cannot always clearly iden-
tify objects and complex traffic conditions.
In these cases, PRE-SAFE
®Brake may:
Rgive an unnecessary warning and then
brake the vehicle
Rnot give a warning or intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and be ready to brake, especially if
PRE-SAFE
®Brake warns you. Terminate the
intervention in a non-critical driving situation.
GWARNING
PRE-SAFE
®Brake cannot always clearly iden-
tify people, especially if they are moving. In
these cases, PRE-SAFE
®Brake cannot inter-
vene. There is a risk of an accident.
Always pay particular attention to the traffic
situation and be ready to brake, especially if
PRE-SAFE
®Brake warns you.
In order to maintain the appropriate distance to
the vehicle in front and thus prevent a collision,
you must apply the brakes yourself.
GWARNING
PRE-SAFE
®Brake does not react:
Rto small people, e.g. children
Rto animals
Rto oncoming vehicles
Rto crossing traffic
Rwhen cornering
As a result, PRE-SAFE
®Brake may neither
give warnings nor intervene in all critical sit-
uations. There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake.
In the event of snowfall or heavy rain, the rec-
ognition can be impaired.
Driving safety systems77
Safety
Z
Recognition by theradar sensor system is also
impaire dif:
Rthere is dirt on th esensor sor anythin gelse
covering th esensor s
Rthere is interferenc eby other radar source s
Rthere are strongradar reflections, for exam-
ple in parking garages
Ra narrow vehicl eis traveling in front, e.g. a
motorbike
Ra vehicl eis traveling in fron ton adifferen tlin e
relative to th ecenter of your vehicl e
Recognition by th ecamera system is also
impaire din th eevent of:
Rdirt on th ecamera or if th ecamera is covered
Rglar eon th ecamera system, e.g. from th esun
bein glow in th esk y
Rdarkness
Ror if:
-pedestrian smov equickly, e.g. int oth epat h
of th evehicl e
-thecamera system no longer recognizes a
pedestrian as aperson due to special cloth -
ing or other objects
-a pedestrian is concealed by other objects
-th etypical outlin eof aperson is no tdistin-
guishable from th ebackgroun d
Followin gdamag eto th efron ten dof th evehicle,
hav eth econfiguration and operation of th e
radar sensor schecke dat aqualified specialist
workshop. This also applie sto collision sat slow
speeds wher ethere is no visible damag eto th e
fron tof th evehicle.
Followin gdamag eto th
ew
indshield, hav eth e
configuration and operation of th ecamera sys-
te m checke dat aqualified specialist workshop.
Function
XTo activate/deactivate: activateor deacti -
vat ePRE-SAF E®Brake in th eon-board com-
puter (Ypage 247).
If th ePRE-SAF E®Brake is no tactivated, th e
æ symbol appear sin th emultifunction dis-
play.
Starting at aspee dof aroun d 4mph (7 km/h),
this function warn syou if you rapidly approac h a
vehicl ein front. An intermittent warning tone
will then soun dand th e· distanc ewarning
lamp will ligh tup in th einstrumen tcluster.
XBrake immediately to defuse th esituation .
or
XTak eevasive action provide dit is saf eto do
so.
PRE-SAF E
®Brake can also brak eth evehicl e
automatically under th efollowin gconditions:
Rth edriver and front-passenger hav etheir seat
belt sfastene d
and
Rth evehicl espee dis between approximately
4 mph (7 km/h) and 12 4mph (20 0km/h)
At speeds of up to approximately 44 mph
(70 km/h) PRE-SAF E
®Brake can also detect:
Rstationary objects in th epat hof your vehicle,
e.g. stoppe dor parked vehicles
Rpedestrian sin th epat hof your vehicl e
iIf there is an increased ris kof acollision ,
preventive passenger protection measures
(PRE-SAF E
®)are triggered (Ypage 60).
If th eris kof collision wit hth evehicl ein fron t
re
main sand you do no tbrake, tak eevasive
action or accelerate significantly, th evehicl e
may perfor mautomatic emergenc ybraking ,up
to th epoin tof full brak eapplication .Automatic
emergenc ybraking is no tperformed until imme-
diately prio rto an imminent accident.
You can preven tth eintervention of th ePRE -
SAFE
®Brake at any time by:
Rdepressing th eaccelerato rpedal further.
Ractivating kickdown .
Rreleasingth ebrak epedal .
The braking action of PRE-SAF E®Brake is ended
automatically if:
Ryou maneuve rto avoi dth eobstacle.
Rthere is no longer aris kof collision .
Rthere is no longer an obstacle detecte din
fron tof your vehicle.
STEER CONTROL
General information
STEE RCONTROL help syou by transmitting a
noticeable steering force to th esteering whee l
in th edirection require dfor vehicl estabilization .
78Driving safety systems
Safety