
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 before the intervention
of PRE-SAFE ®
PLUS.
PRE-SAFE ®
PLUS does not intervene:
R if the vehicle is reversing
R when the vehicle is towing a trailer and there
is a risk of a rear-end collision
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:
R if the radar sensor system detects that a
head-on collision is imminent, the seat belts
are pre-tensioned
R if the radar sensor system detects that a rear-
end collision is imminent:
- the rear hazard warning lamps are activa-
ted and flash at a higher frequency
- 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-
celled:
R if the accelerator pedal is depressed when a
gear is engaged
R if the risk of a collision passes or is no longer
detected
R if 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:
R the hazard lamps are switched on
R the emergency lighting is switched on
R the vehicle doors are unlocked
R the front side windows are lowered
R vehicles with the memory function: the elec-
trically adjustable steering wheel is raised
R the engine is switched off and the fuel supply
is cut off
R vehicles with the Mercedes-Benz emergency
call system: automatic emergency call Children in the vehicle
Important safety notes
Accident statistics show that children secured
in the rear seats are safer than children secured in the front-passenger seat. For this reason,
Mercedes-Benz strongly advises that you install
a child restraint system on a rear seat. Children are generally better protected there.
If a child younger than twelve years old and
under 1.50 min height is travelling in the vehi-
cle:
R always secure the child in a child restraint
system suitable for Mercedes-Benz vehicles.
The child restraint system must be appropri-
ate to the age, weight and size of the child.
R be sure to observe the instructions and safety
notes in this section in addition to the child
restraint system manufacturer's installation
instructions.
R be sure to observe the instructions and safety
notes on the automatic front-passenger front airbag deactivation system (Y page 49).56
Children in the vehicleSafety 

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 68). 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.
Braking 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 System
PLUS) with Cross-Traffic Assist
General information BAS PLUS can help you to minimise the danger
of 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 Observe the important safety notes in the
"Driving safety systems" section (Y page 68).
BAS PLUS is available only 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:
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 69).
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 Driving safety systems
69Safety
Z 

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 following situations:
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 following situations:
R dirt on the camera or obscured camera
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 pedestrian is not
distinguishable 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 low 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. Function To avoid a collision, BAS PLUS calculates the
brake pressure necessary if:
R you approach an obstacle and
R BAS PLUS has detected a danger of collision
At speeds of under30 km/h:if you depress the
brake pedal, BAS PLUS is activated. Braking
assistance from BAS PLUS is provided at the last
possible moment.
At speeds of above30 km/h:if you depress the
brake pedal sharply, BAS PLUS automatically
increases the brake pressure to a degree 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.
At speeds of up to approximately 70 km/h, BAS
PLUS can 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 that move in the
detection range of the sensors and are detec- ted
i If BAS PLUS demands particularly high brak-
ing force, preventative passenger protection
measures (PRE-SAFE ®
) are activated simulta-
neously (Y page 55).
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 the danger of collision has passed
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 information i
Observe the "Important safety notes" sec-
tion (Y page 68).
COLLISION PREVENTION ASSIST PLUS consists of a distance warning function with an autono- 70
Driving safety systemsSafety 

mous braking function and Adaptive Brake
Assist.
COLLISION PREVENTION ASSIST PLUS can help you to minimise the danger of collision with thevehicle in front or reduce the effects of such a
collision.
If COLLISION PREVENTION ASSIST PLUS
detects a danger of collision, you will be warned
visually and audibly. If you do not react to the
visual and audible collision warning, autono-
mous braking can be initiated in critical situa-
tions. 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 following situations:
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 the COLLISION PRE-
VENTION ASSIST PLUS system has been serv-
iced
Observe the important safety notes in the
"Running-in notes" section (Y page 143).
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 low
speeds where there is no visible damage to the front of the vehicle.
Activating/deactivating The COLLISION PREVENTION ASSIST PLUS is
automatically active when the ignition is
switched on.
You can activate or deactivate COLLISION PRE-
VENTION ASSIST PLUS in the on-board com-
puter (Y page 241). When the system is deac-
tivated, the distance warning function and the
autonomous braking function are also deactiva-
ted. If COLLISION PREVENTION ASSIST PLUS is
deactivated, the
æsymbol appears on the
assistance display.
Distance warning function General information
The distance warning function can help you to
minimise the risk of a rear-end collision with a
vehicle ahead or reduce the effects of such a
collision. If the distance warning function
detects a risk of collision with the vehicle in
front, you will be warned visually and audibly.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 68). 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. Driving safety systems
71Safety Z 

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 will then
light up on the instrument cluster.
R of approximately 7 km/h or more if you are
rapidly approaching a vehicle in front. An
intermittent warning tone will then sound and the · distance warning lamp will light up
on the instrument cluster.
X Brake immediately 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, certain com-
plex 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.
Vehicles without DISTRONIC PLUS: the
autonomous braking function is available in the
following speed ranges:
R 7–105 km/h for moving objects
R 7–50 km/h for stationary objects
Vehicles with DISTRONIC PLUS: the autono-
mous braking function is available in the follow-
ing speed ranges:
R 7–200 km/h for moving objects
R 7–50 km/h for stationary objects
Due to the nature of the system, complex but
non-critical driving conditions may also cause
the autonomous braking function to engage. If the autonomous braking function demands
particularly high braking force, preventative
passenger protection measures (PRE-SAFE ®
)
are activated simultaneously (Y page 55).
Adaptive Brake Assist General information
i Observe the "Important safety notes" sec-
tion (Y page 68).
With the help of the radar sensor system, Adap- tive Brake Assist 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
7 km/h. It uses the radar sensor system 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 brake pressure, preventative passenger
protection measures (PRE-SAFE ®
) are activated
simultaneously (Y page 55).
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 a danger of collision with the vehicle in front
no longer exists
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 68).72
Driving safety systemsSafety 

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, complex but
non-critical driving conditions may also cause
Brake Assist to engage.
If Adaptive Brake Assist is not available due to a malfunctioning radar sensor system, the brake
system remains available with full brake boost-
ing effect and BAS. Adaptive brake lights
The adaptive brake lights warn following traffic
in an emergency braking situation:
R by flashing brake lamps
R by activating the hazard warning lamps
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. You can also switch off the hazard warning
lamps using the hazard warning button
(Y page 117). ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 68).
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) i
Observe the "Important safety notes" sec-
tion (Y page 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, e.g. if the road surface is slippery on one side. In addi-
tion, more drive torque is transferred to the
wheel or wheels with traction.
Traction control remains active if you deactivate
ESP ®
.
Important safety notes i
Read the "Important safety notes" section
(Y page 68). 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. Driving safety systems
73Safety
Z 

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 (Y page 68). 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 283) as well as display
messages (Y page 252). 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 (Y page 186) and hill start
assist (Y page 147). PRE-SAFE
®
Brake
General information PRE-SAFE
®
Brake can help you to minimise the
risk of collision with the vehicle in front or a
pedestrian and to reduce the effects of such a
collision. If PRE-SAFE ®
Brake has detected a
danger of collision, you will be warned visually
and audibly as well as by automatic braking.
i Observe the important safety notes in the
"Driving safety systems" section (Y page 68).
PRE ‑SAFE ®
Brake is available only 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 77).
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.
If you partially apply the brakes, the vehicle is
braked with up to 50% of the full brake 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
PRE-SAFE ®
Brake warns you. Terminate the
intervention in a non-critical driving situation. Driving safety systems
77Safety Z 

G
WARNING
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.
To maintain the appropriate distance to the
vehicle in front and thus prevent a collision, you
must apply the brakes yourself. G
WARNING
PRE-SAFE ®
Brake does not react:
R to small people, e.g. children
R to animals
R to oncoming vehicles
R to crossing traffic
R when 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, detection can be impaired.
Detection by the radar sensor system is also
impaired in the following situations:
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
Detection by the camera system is also impaired
in the following situations:
R dirt on the camera or obscured camera
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 pedestrian is not
distinguishable 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 low 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.
Function X
To activate/deactivate: activate or deacti-
vate PRE-SAFE ®
Brake in the on-board com-
puter (Y page 241).
If the PRE-SAFE ®
Brake is not activated, the
æ symbol appears on the multifunction
display.
This function will issue a warning if: R at a speed of around 30 km/h or more, the
distance maintained to the vehicle travelling
in front is insufficient for several seconds
The · distance warning lamp will then
light up on the instrument cluster.
R at a speed of around 7 km/h or more, you
rapidly approach a vehicle in front or a pedes-
trian
An intermittent warning tone will then sound
and the ·distance warning lamp will light
up on the instrument cluster.
X Brake immediately to rectify the situation.
or
X Take evasive action provided it is safe to do
so. 78
Driving safety systemsSafety