BAS (Brake Assist System)
General information
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
iObserve the "Important safety notes" sec-
tion (Ypage 60).
GWARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
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 60).
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 61).
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
Driving safety systems61
Safety
Z
As a result, BAS PLUS may not intervene in allcritical 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 in the event of:
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 traveling in front, e.g. a
motorbike
Ra vehicle traveling in front on a different line
Rvehicles quickly moving 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
Rthere is glare on the camera system, e.g. from
the sun being low in the sky
Rdarkness
Rif:
-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
Follo wing d
amage 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 (250 km/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
Robjects crossing your path and that are rec-
ognized in the detection range of the sensors
iIf BAS PLUS demands particularly high brak-
ing force, preventative passenger protection
measures (PRE-SAFE
®) are activated simulta-
neously (Ypage 52).
XKeep the brake pedal depressed until the
e
mergency braking situation is over.
ABS prevents the wheels from 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.
62Driving safety systems
Safety
COLLISION PREVENTION ASSIST
PLUS
General information
iObserve the "Important safety notes" sec-
tion (Ypage 60).
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.
Important safety notes
In particular, the detection of obstacles can be
impaired if:
Rthere is dirt on the sensors or anything else
covering the sensors
Rthere is snow or heavy rain
Rthere is interference by other radar sources
Rthere are strong radar reflections, for exam-
ple in parking garages
Ra narrow vehicle traveling in front, e.g. a
motorbike
Ra vehicle traveling in front on a different line
Rnew vehicles or after a service on the COLLI-
SION PREVENTION ASSIST PLUS system
Observe the notes in the section on breaking-
in (
Ypage 133).
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 the
front of the vehicle.
Switching on/off
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 (
Ypage 228). 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.
Distance warning function
General information
The distance warning function 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 the distance warning function
detects that there is a risk of a collision, you will
be warned visually and acoustically.
Important safety notes
iObserve the "Important safety notes" sec-
tion for driving safety systems (Ypage 60).
GWARNING
The distance warning function does not react:
Rto people or animals
Rto oncoming vehicles
Rto crossing traffic
Rwhen 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.
GWARNING
The distance warning function cannot always
clearly identify objects and complex traffic
situations.
In such cases, the distance warning function
may:
Rgive an unnecessary warning
Rnot give a warning
Driving safety systems63
Safety
Z
There is a risk of an accident.
Always pay careful attention to the traffic sit-uation and do not rely solely on the distance
warning function.
Function
Starting at a speed of around 4 mph (7 km/h),
the distance warning function warns you if you
rapidly approach a vehicle in front. An intermit-
tent warning tone will then sound, and the ·
distance warning lamp will light up in the instru-
ment cluster.
XBrake immediately in order to increase the
distance from the vehicle in front.
or
XTake 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 around 44 mph (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:
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 52).
Adaptive Brake Assist
General information
iObserve the "Important safety notes" sec-
tion (Ypage 60).
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
simultaneously (Ypage 52).
XKeep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
64Driving safety systems
Safety
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 60).
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.
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, complicated
but non-critical driving situations may also
cause Adaptive 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 60).
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.
4ETS (Electronic Traction System)
4ETS traction control 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
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.
!Only operate the vehicle for a maximum of
ten seconds on a brake test dynamometer.
Switch off the ignition.
Application of the brakes by ESP
®may oth-
erwise destroy the brake system.
!A function or performance test should only
be carried out on a two-axle dynamometer.
Before you operate the vehicle on such a
dynamometer, please consult a qualified
workshop. You could otherwise damage the
drive train or the brake system.
Driving safety systems65
Safety
Z
Important safety notes
Crosswind Assist does not work ifESP®is deac-
tivated or disabled because of a malfunction.
EBD (electronic brake force distribu-
tion)
General information
EBD monitors and controls the brake pressure
on the rear wheels to improvedriving stabilit y
while braking.
Important safety notes
iObserve the "Important safety notes" sec-
tion for driving safety systems (Ypage 60).
GWAR NING
If EBD ismalfunctioning, the rear wheels can
lock, e.g. under full braking. This increases the
risk of skiddin g and an accident.
You should therefore adapt your driving style
to the different handlin g characteristics. Have
the brake system checked at a qualified spe-
cialist workshop.
Observe information regarding indicator and
warning lamps (
Ypage 268) as wellasdisp lay
messages (Ypage 237).
ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety and
offers increased braking comfort. In addition to
the braking function, ADAPTIVE BRAKE also has
the HOLD function (
Ypage 179) and hillstart
assist (Ypage 138).
PRE-SAFE®Brake
General information
PRE-SAFE®Brake can help you to min imize the
risk of a co llisionwit h a veh icleahead or a
pedestrian, and reduce the effects of such a
co llisio n.IfPRE-SAFE
®Brake has detected a risk
of co llision, you will be warned visually and
acoustical lyas well asby automat icbraking.
iPay attention to the important safety notes
in the "Driving safety systems" section
(
Ypage 60).
PRE‑ SAFE
®Brake isonly availab le invehicles
wit h the Dr iving 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 beoperational.
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 describe din the
"Important safety notes" sec-
tion“ (
Ypage 68).
Important safety notes
GWARNING
PRE-SAFE
®Brake willinitially brake your vehi-
cle bya partial application of the brakes if a
danger of collision isdetected. 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 isa risk of an accident.
Always apply the brakes yourself and try to
take evasive action, provide dit is safe to do
so.
In the event of a partial application of the brakes,
the vehicle isbraked with up to 50% of the full
braking pressure.
GWARNING
PRE-SAFE
®Brake cannot always clearly iden-
tify objects and co mplex 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.
68Driving safety systems
Safety
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.
Recognition by the radar sensor system is also
impaired in the event of:
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 traveling in front, e.g. a
motorbike
Ra vehicle traveling in front on a different line
relative to the center of your vehicle Recognition by the camera system is also
impaired in the event of:
Rdirt on the camera or if the camera is covered
Rthere is glare on the camera system, e.g. from
the sun being low in the sky
Rdarkness
Rif:
-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 o
bjects
-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
XTo activate/deactivate: activate or deacti-
vate PRE-SAFE®Brake in the on-board com-
puter (Ypage 228).
If the PRE-SAFE®Brake is not activated, the
æ symbol appears in the multifunction dis-
play.
If you have activated DSR (
Ypage 180), PRE-
SAFE®Brake is deactivated.
Starting at a speed of around 4 mph (7 km/h),
this function warns you if you rapidly approach a
vehicle in front. An intermittent warning tone
will then sound and the ·distance warning
lamp will light up in the instrument cluster.
XBrake immediately to defuse the situation.
or
XTake evasive action provided it is safe to do
so.
PRE-SAFE
®Brake can also brake the vehicle
automatically under the following conditions:
Rthe driver and front-passenger have their seat
belts fastened
Driving safety systems69
Safety
Z
The SmartKey centrally locks and unlocks the
following components:
Rthe doors
Rthe tailgate
Rthe fuel filler flap
The turn signals flash once when unlocking and
three times when locking.
You can also set an audible signal to confirm
that the vehicle has been locked. The audible
signal can be activated and deactivated using
the on-board computer (
Ypage 230).
You will receive visual and acoustic locking con-
firmation if all components were able to be
locked.
If activated in COMAND or Audio 20, the locator
lighting also lights up in the dark (see separate
operating instructions).
XTo open the tailgate automatically from
outside the vehicle: press and hold theF
button until the tailgate opens.
Vehicles with KEYLESS-GO or KEYLESS-GO start function and EASY-PACK tailgate:
XTo close the tailgate automatically from
outside the vehicle: if the SmartKey is loca-
ted in the immediate vicinity of the vehicle,
press the Fbutton on the SmartKey.
When the tailgate closes you can then release
the button.
KEYLESS-GO
General notes
Bear in mind that the engine can be started by
any of the vehicle occupants if there is a KEY-
LESS-GO key in the vehicle (
Ypage 136).
Locking/unlocking centrally
You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry the
SmartKey with you. You can combine the func-
tions of KEYLESS-GO with those of a conven-
tional SmartKey. Unlock the vehicle by using
KEYLESS-GO, for instance, and lock it using the
& button on the SmartKey.
The driver's door and the door at which the han-
dle is used, must both be closed. The SmartKey
must be outside the vehicle. When locking or
unlocking with KEYLESS-GO, the distance between the SmartKey and the corresponding
door handle must not be greater than 3 ft (1 m).
KEYLESS-GO checks whether a valid SmartKey
is in the vehicle by periodically establishing a
radio connection between the vehicle and the
SmartKey. This happens:
Rwhen starting the engine
Rwhile driving
Rwhen the external door handles are touched
Rduring convenience closing
XTo unlock the vehicle:
touch the inner sur-
face of the door handle.
XTo lock the vehicle: touch sensor surface :
or ;.
Make sure that you do not touch the inner
surface of the door handle.
XConvenience closing feature: touch
recessed sensor surface ;for an extended
period.
Further information on the convenience closing
feature (
Ypage 87).
If you pull on the handle of the tailgate, only the cargo compartment of the vehicle is unlocked.
Deactivating and activating
If you do not intend to use a SmartKey for an
extended period of time, you can deactivate the
KEYLESS-GO function of the SmartKey. The
SmartKey will then use very little power, thereby
conserving battery power. For the purposes of
activation/deactivation, the vehicle must not be
nearby.
SmartKey73
Opening and closing
Z