
If the SmartKey is removed from the ignition
lock or is in position 0, PASSENGER AIR BAG
OFF indicator lamp :does not light up.
The Occupant Classification System (OCS)
categorizes the occupant on the front-
passenger seat using a weight sensor.
The front-passenger front air bag is
deactivated automatically for certain weight
categories.
If the PASSENGER AIR BAG OFF indicator
lamp is lit, the passenger air bag is disabled.
The PASSENGER AIR BAG OFF indicator lamp
shows you the current status.
The system does not deactivate:
R the side impact air bag
R the pelvis air bag
R the window curtain air bag
R the Emergency Tensioning Devices
To be classified correctly, the front passenger
must sit:
R with the seat belt fastened correctly
R in a position that is as upright as possible
with their back against the seat backrest
R with their feet on the floor
The OCS weight sensor reading is affected if
the occupant's weight is transferred, e.g. by
leaning on the armrest.
If the front-passenger seat, the seat cover or
the seat cushion are damaged, have the
necessary repair work carried out at a
qualified specialist workshop.
For safety reasons, Mercedes-Benz
recommends that you only use seat accessories that have been approved by
Mercedes-Benz.
Both the driver and the front passenger
should always observe the PASSENGER AIR
BAG OFF indicator lamp as an indication of
whether or not the front passenger is
positioned correctly. Observe also the air bag
display messages that can be displayed in the
instrument cluster (Y
page 265).
If the driver's air bag deploys, this does not
mean that the front-passenger front air bag
will also deploy.
The OCS may have detected that the seat:
R is empty or occupied by the weight of a
typical child up to twelve months old,
seated in a child restraint system.
R is occupied by a small individual, such as a
young teenager or a small adult.
R is occupied by a child in a child restraint
system whose weight is greater than that
of a typical twelve month old child.
These are examples of when the OCS
deactivates the front-passenger front air bag.
Deactivation takes place although the
collision fulfills the criteria for deploying the
driver's air bag.
For further information, see "Air bag display
messages" (Y page 265).
System self-test G
WARNING
If the 45indicator lamp does not
illuminate, the system is not functioning. You
must contact an authorized Mercedes-Benz
Center before seating any child on the front
passenger seat. G
WARNING
Objects between the seat surface and the
child restraint system could affect the
function of the OCS. This could result in the
front-passenger front air bag not functioning
as intended during an accident. This poses an
increased risk of injury or even fatal injury. 50
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R
if, on vehicles with DISTRONIC PLUS, the
radar sensor system detects an imminent
danger of collision in certain situations.
R in critical driving situations, e.g. when
physical limits are exceeded and the
vehicle understeers or oversteers severely.
PRE-SAFE ®
takes the following measures
depending on the hazardous situation
detected:
R the front seat belts are pre-tensioned.
R the front-passenger seat is adjusted if it is
in an unfavorable position.
R the air pressure in the side bolsters of the
seat cushion and seat backrest of the front
active multicontour seats is increased.
R if the vehicle skids, the sliding sunroof and
the side windows are closed so that only a
small gap remains. On vehicles with a
panorama roof with power tilt/sliding
panel, they are closed completely.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pre-tensioning. The air pressure in
the side bolsters of the active multicontour
seat is reduced again. All settings made by
PRE-SAFE ®
can then be reversed.
If the seat belts are not released:
X When the vehicle is stationary, move the
backrest or seat back slightly.
The seat belt pre-tensioning is reduced and
the locking mechanism is released.
Information about seat belt adjustment, a
convenience function integrated into PRE-
SAFE ®
, can be found in the "Seat belt
adjustment" section (Y page 57).Seat belts
Important safety notes G
WARNING
The seat belt does not offer the intended level
of protection if the backrest is not in the
upright position. When braking or in the event of an accident, you could slide underneath the
seat belt and sustain abdomen or neck
injuries, for example. This poses an increased
risk of injury or even fatal injury.
Adjust the seat properly before beginning
your journey. Always make sure that the seat
is in the upright position.
G
WARNING
Seat belts cannot protect as intended, if:
R they are damaged, extremely dirty,
bleached or dyed
R the seat belt buckle is damaged or
extremely dirty
R the Emergency Tensioning Devices or the
belt anchorage has been modified.
Damage caused to seat belts in an accident
may not be visible, e.g. by splinters of glass.
Modified or damaged seat belts can tear or
fail, for example in the event of an accident.
Modified Emergency Tensioning Devices may
be deployed unintentionally or fail to be
deployed when required. There is an
increased risk of injury, possibly even fatal.
Never modify seat belts, Emergency
Tensioning Devices, seat belt anchorages and
inertia reels. Ensure that seat belts are not
damaged or worn and are clean.
Only use seat belts that have been approved
for your vehicle by Mercedes-Benz.
The use of seat belts and infant and child
restraint systems is required by law in:
R all 50 states
R the U.S. territories
R the District of Columbia
R all Canadian provinces
Even where this is not required by law, all
vehicle occupants should correctly fasten
their seat belts before starting the journey.
i See "Children in the vehicle"
(Y page 60) for further information on
infants and children traveling in the vehicle
as well as on child restraint systems. Occupant safety
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ABS works from a speed of about 5 mph
(8 km/h), regardless of road-surface
conditions. ABS works on slippery surfaces,
even if you only brake gently.
Braking X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking
situation is over.
X To make a full brake application:
depress the brake pedal with full force.
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
The pulsating brake pedal can be an
indication of hazardous road conditions, and
functions as a reminder to take extra care
while driving. 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 i
Observe the "Important safety notes"
section ( Ypage 67). G
WARNING
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 X
Keep 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 i
Observe the "Important safety notes"
section ( Ypage 67).
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:
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
vehicle 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 system is still available
with complete brake boosting effect and BAS.
i Observe the restrictions described in the
"Important safety notes"
section“ (Y page 69).
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. 68
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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
situation and be ready to brake. Terminate the
intervention in a non-critical driving situation. G
WARNING
BAS PLUS does not react:
R to small people, e.g. children
R to animals
R to oncoming vehicles
R when cornering
As a result, BAS PLUS may not intervene in all
critical situations. There is a risk of an
accident.
Always pay careful attention to the traffic
situation and be ready to brake.
In the event of snowfall or heavy rain, the
recognition can be impaired.
Recognition by the radar sensor system is
also impaired in the event of:
R dirt on the sensors or anything else
covering the sensors
R interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
R vehicles quickly moving into the radar
sensor system detection range Recognition by the camera system is also
impaired in the event of:
R
dirt on the camera or if the camera is
covered
R there is 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 recognizes
a pedestrian as a person due to special
clothing or other objects
- a pedestrian is concealed by other
objects
- the typical outline of a person is not
distinguishable 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 low 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
system checked at a qualified specialist
workshop.
Function To avoid a collision, BAS PLUS calculates the
brake force necessary if:
R
you approach an obstacle, and
R BAS PLUS has detected a risk of 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
pressure 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. Driving safety systems
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front. An intermittent warning tone will then
sound, and the ·distance warning lamp
will light up in the instrument cluster.
X Brake immediately in order to increase the
distance from the vehicle in front.
or
X Take evasive action, provided it is safe to
do so.
Due to the nature of the system, particularly
complicated but non-critical driving
conditions may also cause the system to
display a warning.
With the help of the radar sensor system, the
distance warning function can detect
obstacles that are in the path of your vehicle
for an extended period of time.
From a speed of around 40 mph (70 km/h),
the distance warning function can also react
to stationary obstacles, such as stopped or
parked vehicles.
If you approach an obstacle and the distance
warning function detects a risk of a collision,
the system will initially alert you both visually
and acoustically.
In particular, the detection of obstacles can
be impaired if:
R dirt on the sensors or anything else
covering the sensors
R snow or heavy rain
R interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
relative to the center of your vehicle
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. Adaptive Brake Assist i
Observe the "Important safety notes"
section (Y page 67). G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic
situations.
In such cases, Adaptive Brake Assist may:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic
situation 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 to stationary obstacles
R when cornering
As a result, Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake.
Adaptive Brake Assist aids you in braking
during hazardous situations at speeds above
4 mph (7 km/h) and uses the radar sensor
system to evaluate the traffic situation.
With the help of Adaptive Brake Assist, the
distance warning signal can detect obstacles
that are in the path of your vehicle for an
extended period of time.
Should you approach an obstacle and
Adaptive Brake Assist has detected a risk of
collision, Adaptive Brake Assist calculates the
braking force necessary to avoid a rear-end
collision. Should you apply the brakes
vigorously, Adaptive Brake Assist will Driving safety systems
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automatically increase the braking force to a
level suitable for the traffic conditions.
X Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if:
R you release the brake pedal
R there is no longer any danger of a rear-end
collision
R no obstacle is detected in front of your
vehicle
Adaptive Brake Assist is then deactivated.
Up to vehicle speeds of around 155 mph
(250 km/h), adaptive Brake Assist is capable
of reacting to moving objects that have
already been recognized as such at least once
over the period of observation. Adaptive
Brake Assist does not react to stationary
obstacles.
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.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or anything else
covering the sensors
R snow or heavy rain
R interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
relative to the center of your vehicle
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. ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes"
section (Y page 67).
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 vehicle 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) ETS/4ETS traction control is part of ESP
®
.
Traction control brakes the drive wheels
individually 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
transferred to the wheel or wheels with
traction.
Traction control remains active, even if you
deactivate ESP ®
.
Important safety notes i
Observe the "Important safety notes"
section (Y page 67). G
WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilize the vehicle. Additionally, further
driving safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
! Vehicles with 4MATIC: switch off the
ignition when the parking brake is being
tested on a brake dynamometer. 72
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PRE-SAFE
®
Brake
General information i
Observe the "Important safety notes"
section (Y page 67).
PRE-SAFE ®
Brake is only available for
vehicles with the Driving Assistance 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
vehicle can be detected.
PRE-SAFE ®
Brake detects pedestrians using
typical characteristics such as the body
contours and posture of a person standing
upright.
i Observe the restrictions described in the
"Important safety notes"
section“ (Y page 76).
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.
Important safety notes G
WARNING
PRE-SAFE ®
Brake will initially brake your
vehicle 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,
particularly 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.
G
WARNING
PRE-SAFE ®
Brake cannot always clearly
identify objects and complex traffic
conditions.
In these cases, PRE-SAFE ®
Brake may:
R give an unnecessary warning and then
brake the vehicle
R not 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.
In order 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
situations. There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake.
In the event of snowfall or heavy rain, the
recognition can be impaired.
Recognition by the radar sensor system is
also impaired in the event of:
R dirt on the sensors or anything else
covering the sensors
R interference by other radar sources
R there are strong radar reflections, for
example in parking garages 76
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R
a narrow vehicle traveling in front, e.g. a
motorbike
R a 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:
R dirt on the camera or if the camera is
covered
R there is 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 recognizes
a pedestrian as a person due to special
clothing or other objects
- a pedestrian is concealed by other
objects
- the typical outline of a person is not
distinguishable 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 low 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
system checked at a qualified specialist
workshop.
Function X
To activate/deactivate: activate or
deactivate PRE-SAFE ®
Brake in the on-
board computer (Y page 247).
If the PRE-SAFE ®
Brake is not activated, the
æ symbol appears in the multifunction
display.
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.
X Brake immediately to defuse the situation.
or
X Take evasive action provided it is safe to do
so.
PRE-SAFE ®
Brake can also brake the vehicle
automatically under the following conditions:
R the driver and front-passenger have their
seat belts fastened
and
R the vehicle speed is between
approximately 4 mph (7 km/h) and
124 mph (200 km/h)
At a speed of up to approximately 44 mph
(70 km/h), PRE-SAFE ®
Brake can also detect:
R stationary objects in the path of your
vehicle, e.g. stopped or parked vehicles
R pedestrians in the path of your vehicle
i If there is an increased risk of collision,
preventive passenger protection measures
(PRE-SAFE ®
) are activated.
If the risk of collision with the vehicle in front
remains and you do not brake, take evasive
action or accelerate significantly, the vehicle
may perform automatic emergency braking,
up to the point of full brake application.
Automatic emergency braking is not
performed until immediately prior to an
imminent accident.
You can prevent the intervention of the PRE-
SAFE ®
Brake at any time by:
R depressing the accelerator pedal further.
R activating kickdown.
R releasing the brake pedal.
The braking action of PRE-SAFE ®
Brake is
ended automatically if:
R you maneuver to avoid the obstacle.
R there is no longer a risk of collision.
R there is no longer an obstacle detected in
front of your vehicle. Driving safety systems
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