
tamper with electronic components or their
software.
In this section, you will learn the most
important facts about the restraint system
components of the vehicle.
The restraint system consists of:
R seat belts
R child restraint systems
R LATCH-type (ISOFIX) child seat anchors
Additional protection is provided by:
R SRS (Supplemental Restraint System)
R NECK-PRO head restraints
R PRE-SAFE ®
R Cabriolet: roll bar
R air bag system components with:
-PASSENGER
AIR BAG OFF indicator lamp
- front-passenger seat with Occupant
Classification System (OCS)
The different air bag systems work
independently of each other. The protective
functions of the system work in conjunction
with each other. Not all air bags are deployed
in an accident.
i See "Children in the vehicle" for
information on infants and children
traveling with you in the vehicle restraint
systems for infants and children
(Y page 58). SRS (Supplemental Restraint System)
Introduction SRS consists of:
R
6 SRS warning lamp
R Air bags
R Air bag control unit with crash sensors
R Emergency Tensioning Devices
R Belt force limiters
SRS reduces the risk of occupants coming
into contact with the vehicle's interior in the
event of an accident. It can also reduce the effect of the forces to which occupants are
subjected during an accident.
SRS warning lamp
G
WARNING
The SRS self-check has detected a
malfunction if the 6 SRS indicator lamp:
R does not light up at all
R does not go out after approximately four
seconds after the engine is started
R lights
up after the engine is started or while
the vehicle is in motion
For your safety, Mercedes-Benz strongly
recommends that you have the system
checked as soon as possible at a qualified
specialist workshop. SRS may otherwise fail
to activate when it is needed in the event of
an accident, which could lead to serious or
fatal injuries. SRS might also be activated
unexpectedly and unnecessarily, which could
also result in injury.
In addition, work carried out improperly on
SRS may render SRS inoperative or cause
unintended air bag deployment. Work on the
SRS system should only be carried out by
qualified specialist personnel. Consult a
qualified specialist workshop.
If it is necessary to modify an air bag system
to accommodate a person with disabilities,
contact an authorized Mercedes-Benz Center
for details. USA only: for further information,
contact our Customer Assistance Center at
1-800-FOR-MERCedes (1-800-367-6372).
SRS functions are checked regularly when
you switch on the ignition and when the
engine is running. Therefore, malfunctions
can be detected in good time.
The 6 SRS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out no later than a few seconds
after the engine is started.
The SRS components are in operational
readiness when the SRS 6 indicator lamp
goes out while the engine is running. Occupant safety
39
Safety Z

bag is deactivated. Should the
45
indicator lamp not illuminate or go out while
the restraint is installed, please check
installation. Periodically check the
45 indicator lamp while driving to
make sure that the 45 indicator
lamp is illuminated. If the 45
indicator lamp goes out or remains out, do
not transport a child on the front-passenger
seat until the system has been repaired.
A child in a rear-facing child restraint on the
front-passenger seat will be seriously
injured or even killed if the front-passenger
front air bag inflates.
R If you place a child in a forward-facing child
restraint on the front-passenger seat:
-move the seat as far back as possible
- use the proper child restraint
recommended for the age, size and
weight of the child
- secure child restraint with the vehicle's
seat belt according to the child seat
manufacturer's instructions
R For children larger than the typical 12-
month-old child, the front-passenger front
air bag may or may not be activated. G
WARNING
If the red 6 SRS warning lamp in the
instrument cluster and the 45
indicator lamp light up simultaneously, the
OCS is malfunctioning. The front passenger
front air bag will be deactivated in this case.
Have the system checked by qualified
technicians as soon as possible. Contact an
authorized Mercedes-Benz Center.
Only
have the seat repaired or replaced at an
authorized Mercedes-Benz Center.
In order to ensure proper operation of the air
bag system and OCS:
R Sit with the seat belt properly fastened in a
position that is as upright as possible with
your back against the seat backrest.
R When seated, a passenger should not
position him/herself in such a way as to cause the passenger's weight to be lifted
from
the seat cushion as this may result in
the OCS being unable to correctly
approximate the passenger's weight
category.
R Read and observe all warnings in this
chapter. If the SmartKey has been removed from the
ignition lock or is in position 0, the
45 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.
45 indicator lamp : shows you the
current status. If
45 indicator lamp : lights up, the
front-passenger air bag is disabled.
The system does not deactivate:
R the side impact air bag
R the pelvis air bag
R the window curtain air bag (Coupe)
R the front-passenger head bag (Cabriolet)
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 floor48
Occupant safety
Safety

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 45
indicator lamp to determine whether or not
the front passenger is positioned correctly.
Also observe the air bag display messages,
which appear in the instrument cluster
(Y page 235).
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 235).
System self-test G
WARNING
If the 4 5 indicator 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
Never place anything between seat cushion
and
child seat (e.g. a pillow), since it reduces
the effectiveness of the OCS. The underside
and rear side child restraint system must be
placed entirely on the seat cushion and the
backrest of the front-passenger seat
backrest.
If necessary, adjust the tilt of the passenger
seat backrest.
An incorrectly mounted child seat could cause
injuries to the child in case of an accident,
instead of increasing protection for the child.
Follow the manufacturer's instructions for
installation of child restraint systems.
The 45 indicator lamp lights up:
R if you turn the SmartKey in the ignition lock
to position 1 or 2
R if you press the KEYLESS-GO Start/Stop
button once or twice on vehicles with
KEYLESS-GO
R if an adult is seated properly on the front-
passenger seat and the OCS classifies the
occupant as an adult
The 45 indicator lamp goes out
after approximately six seconds.
If the seat is not occupied and the OCS
detects that the front-passenger seat is
empty, the 45 indicator lamp will
continue to light up. The 45 front-
passenger front air bag warning lamp then
stays lit continuously.
For more information about the OCS, see
"Problems with the Occupant Classification
System" ( Y page 50). Occupant safety
49
Safety Z

Example: Coupe
X
Press release button ? on belt buckle =.
X Slide belt tongue ; back to belt sash
guide :.
Belt warning for the driver and front
passenger Regardless of whether the driver's and front-
passenger seat belts have already been
fastened, the 7 seat belt warning lamp
lights
up for six seconds each time the engine
is started. It then goes out if the driver and
the front passenger have fastened their seat
belts.
If the driver's seat belt is not fastened when
the engine is started, an additional warning
tone will sound. The warning tone goes out
after approximately six seconds or once the
driver's seat belt is fastened.
If after six seconds the driver or front
passenger have not fastened their seat belts
and the doors are closed, the 7 seat belt
warning lamp lights up:
R until the driver's or front passenger's seat
belt is fastened
R once the vehicle has exceeded a speed of
15 mph (25 km/h), in addition a warning
tone will sound with increasing intensity for up to 60 seconds or until the driver's or
front-passenger seat belt is fastened.
If the driver/front passenger unfasten their
seat belt while the vehicle is in motion, the
7 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases after 60 seconds
even if the driver or front passenger has still
not fastened their seat belt. The 7 seat
belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed again exceeds 15 mph (25 km/h).
The 7 seat belt warning lamp only goes
out if:
R both the driver and the front passenger
have fastened their seat belts.
or
R the vehicle is stationary and a door is open.
i For more information on the 7 seat
belt warning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belts" ( Y page 257).
Emergency Tensioning Devices, belt
force limiters G
WARNING
Pyrotechnic Emergency Tensioning Devices
that have been deployed must be renewed.
For
your safety, when disposing of Emergency
Tensioning Devices, always observe the
safety instructions. These are available from
any authorized Mercedes-Benz Center.
The PRE-SAFE ®
system has electrically
operated reversible pre-tensioners that do
not require replacement after activation.
! If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise, the Emergency Occupant safety
57
Safety Z

R
EBD ( electronic brake force distribution)
(Y page 67)
R ADAPTIVE BRAKE
(Y page 67)
R PRE-SAFE ®
Brake (Y page 67) Important safety notes
If you fail to adapt your driving style or
become distracted, the driving safety
systems can neither reduce the risk of
accident nor override the laws of physics.
Driving safety systems are merely aids
designed to assist driving. You are
responsible for the distance to the vehicle in
front, for vehicle speed and for braking in
good
time. Always adapt your driving style to
suit the prevailing road and weather
conditions and maintain a safe distance from
the vehicle in front. Drive carefully.
i The driving safety systems described only
work as effectively as possible when there
is adequate contact between the tires and
the road surface. Please pay special
attention to the notes on tires,
recommended minimum tire tread depths,
etc. (Y page 322).
In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible. ABS (Anti-lock Braking System)
Important safety notes i
Observe the "Important safety notes"
section ( Y page 64).G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking
characteristics may be severely impaired.
Additionally, further driving safety systems
are
deactivated. There is an increased danger
of skidding and accidents. Drive on carefully. Have ABS checked
immediately at a qualified specialist
workshop.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become
inoperative. Observe the information
on the ABS warning lamp ( Y page 258) and
display messages which may be shown in the
instrument cluster (Y page 229).
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
ABS works from a speed of about 5 mph
(8 km/h) upwards, regardless of road-surface
conditions. ABS works on slippery surfaces,
even if you only brake gently.
The yellow ! ABS warning lamp in the
instrument cluster lights up when the ignition
is switched on. It goes out when the engine is
running.
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)
i Observe the "Important safety notes"
section ( Y page 64). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident. 64
Driving safety systems
Safety

R
to crossing traffic
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.
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.
i This device has been approved by the FCC
as a "Vehicular Radar System". The radar
sensor is intended for use in an automotive
radar system only. Removing, altering or
tampering with the device will void any
warranties, and is not permitted by the
FCC. Do not tamper with, alter, or use the
device in any non-approved way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment. ESP
®
(Electronic Stability Program)
Important safety notes i
Observe the "Important safety notes"
section ( Y page 64).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.
Application of the brakes by ESP ®
may
otherwise destroy the brake system. Vehicles without 4MATIC: when towing your
vehicle with the rear axle raised, it is
important that you observe the notes on
ESP
®
(Y page 316).
ESP ®
is deactivated if the å warning lamp
in the instrument cluster lights up
continuously when the engine is running.
If the ÷ warning lamp and the å
warning lamp are lit continuously, ESP ®
is not
available due to a malfunction.
Observe the information on warning lamps
(Y page 259) and display messages which
may be shown in the instrument cluster
(Y page 229).
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.
If ESP ®
intervenes, the ÷ ESP®
warning
lamp flashes in the instrument cluster.
If ESP ®
intervenes:
X Do not deactivate ESP ®
under any
circumstances.
X Only depress the accelerator pedal as far
as necessary when pulling away.
X Adapt your driving style to suit the
prevailing road and weather conditions.
i Only use wheels with the recommended
tire sizes. Only then will ESP ®
function
properly.
ETS/4ETS (Electronic Traction System) 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. On vehicles with 4MATIC, more 66
Driving safety systems
Safety

drive torque is also transferred to the wheel
or wheels with traction.
Traction control remains active if you
deactivate ESP
®
.
Deactivating/activating ESP ®G
WARNING
If you deactivate ESP ®
, ESP ®
no longer
stabilizes the vehicle. There is an increased
risk of skidding and an accident.
Only deactivate ESP ®
in the situations
described in the following.
! Avoid spinning the driven wheels for an
extended period with ESP ®
deactivated.
You
could otherwise damage the drivetrain.
X To deactivate: (Y page 222).
The å ESP ®
OFF warning lamp in the
instrument cluster lights up.
X To activate: (Y page 222).
The å ESP ®
OFF warning lamp in the
instrument cluster goes out.
ESP ®
is activated automatically when the
engine is started.
The ECO start/stop function switches the
engine off automatically if the vehicle stops
moving.
The engine starts automatically when
the driver wants to pull away again. ESP ®
remains in its previously selected status.
Example: if ESP ®
was deactivated before the
engine was switched off, ESP ®
remains
deactivated when the engine is switched on
again.
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ ESP®
warning lamp in
the instrument cluster flashes. In such
situations, ESP ®
will not stabilize the vehicle.
It may be best to deactivate ESP ®
in the
following situations:
R when using snow chains
R in deep snow
R on sand or gravel If you deactivate ESP
®
:
R ESP ®
no longer improves driving stability.
R traction control is still activated.
R ESP ®
still provides support when you
brake.
R engine torque is not limited and the drive
wheels are able to spin. The spinning
wheels produce a cutting effect for better
traction. EBD (electronic brake force
distribution)
i Observe the "Important safety notes"
section ( Y page 64). G
WARNING
If EBD has malfunctioned, the rear wheels can
still 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
specialist workshop.
Observe information regarding indicator and
warning lamps ( Y page 258) as well as
display messages ( Y page 230).
EBD monitors and controls the brake
pressure on the rear wheels to improve
driving stability while braking. 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 189) and hill start assist
(Y page 153). PRE-SAFE
®
Brake
i Observe the "Important safety notes"
section ( Y page 64). Driving safety systems
67
Safety Z

PRE-SAFE
®
Brake is only available in vehicles
with DISTRONIC PLUS.
PRE-SAFE ®
Brake can help you to minimize
the risk of a collision with a vehicle ahead or
reduce the effects of such a collision. If PRE-
SAFE ®
Brake detects a risk of collision, you
will be warned visually and acoustically as
well as by automatic braking. PRE-SAFE ®
Brake cannot prevent a collision without your
intervention.
Above a speed of around 4 mph (7 km/h), this
function warns you if you are very quickly
approaching 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 in order to increase the
distance from the vehicle in front.
or
X Take evasive action provided it is safe to do
so.
If the driver and front passenger have their
seat
belt fastened, PRE-SAFE ®
Brake can also
brake the vehicle automatically at speeds
from approximately 4 mph (7 km/h) to
approximately 124 mph (200 km/h).
Due to the nature of the system, particularly
complicated driving conditions may cause
unnecessary warnings or the unnecessary
intervention of PRE-SAFE ®
Brake.
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 any danger of a rear-end
collision.
R there is no longer an obstacle detected in
front of your vehicle. With the help of the radar sensor system,
PRE-SAFE
®
Brake can detect obstacles that
are in front of your vehicle for an extended
period of time.
At speeds of up to 40 mph (70 km/h
), PRE-
SAFE ®
Brake can also detect stationary
obstacles, for example, stopped or parked
vehicles.
If you approach an obstacle and PRE-SAFE ®
Brake detects a risk of a collision, the system
will alert you both visually and acoustically. If
you do not brake or take evasive action, the
system will warn you by automatically braking
the vehicle gently. If there is an increased risk
of collision, preventive passenger protection
measures (PRE-SAFE ®
) are activated
(Y page 52). If, at speeds over 20 mph
(30 km/h), a risk of collision remains and you
do not brake, take evasive action or
significantly accelerate, automatic braking
may be performed up to the level of
emergency braking. Automatic emergency
braking is not performed until immediately
prior to an accident that can no longer be
avoided. 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 also brake.
Automatic emergency braking cannot prevent
a collision. There is a risk of an accident.
Always apply the brakes yourself and try to
take evasive action. 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. 68
Driving safety systems
Safety