
SRS (Supplemental Restraint System)
Introduction SRS consists of:
R
The 0020 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 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 0020 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 0020SRS warning lamp
goes out while the engine is running. G
WARNING
The SRS self-chec khas detected a
malfunction if the 0020SRS indicator lamp:
R does no tlight up at all
R does not go out after approximately four
seconds after the engine is started
R comes on after the engine was started or
while driving.
For your safety, Mercedes-Ben zstrongly
recommends tha tyou have the system
checked as soon as possible at an authorized
Mercedes-Benz Center. 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 an
authorized Mercedes-Benz Center.
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).
Safety guidelines for seat belts,
Emergency Tensioning Devices (ETDs)
and air bags G
WARNING
R Damaged seat belts or seat belts that have
been subjected to stress in an accident
must be replaced. Their anchoring points
must also be checked. Only use seat belts
installed or supplied by an authorized
Mercedes-Benz Center.
R Air bags and pyrotechnic Emergency
Tensioning Devices (ETDs) contain
perchlorate material, which may require
special handling and regard for the
environment.C heck your national disposal
guidelines. California residents, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm.
R Air bags and ETDs are designed to function
on a one-time-only basis. An air bag or ETD
that has deployed must be replaced.
R Do not pass seat belts over sharp edges.
They could tear.
R Do not make any modification that could
change the effectiveness of the seat belts.
R Do not bleach or dye seat belts as this may
severely weaken them. In a crash they may
not be able to provide adequate protection.
R No modifications of any kind may be made
to any components or wiring of the SRS. Occupant safety
41Safety
Z

weight sensor readings fro
mthe front-
passenger seat, remain illuminated or go out.
With the 001B001D indicator lamp
illuminated, the front-passenger front air bag
is deactivated. With the 001B001Dindicator
lamp out, the front-passenger front air bag is
activated.
When the OCS senses that the front-
passenger seat occupant is classified as an
adultors omeone larger than a small
individual, the 001B001Dindicator lamp will
illuminate for approximately 6seconds when
the engine is started and then go out,
indicating that the front-passenger front air
bag is activated.
If the 001B001D indicator lamp is illuminated,
the front-passenger front air bag is
deactivated and will not be deployed.
If the 001B001D indicator lamp is not
illuminated, the front-passenger fron tair bag
is activated and will be deployed:
R in the event of certain frontal impacts
R if impact exceeds a preset deployment
threshold
R independently of the side impact air bags
If the front-passenger front air bag is
deployed, the rate of inflation will be
influenced by:
R the rate of relevant vehicle deceleratio nas
assessed by the air bag control unit
R the fron tpassenger's weigh tcategory as
identified by OCS
For further information, see "Air bag display
messages" (Y page 238). G
WARNING
According to accident statistics, children are
safe rwhen properly restrained on the rear
seats than on the front-passenger seat. Thus,
we strongly recommend that children be
placed in the rear seats whenever possible.
Regardless of seating position, children 12
years old and under must be seated and
properly secured in an appropriate infant
restraint, toddler restraint, or booster seat recommended for the size and weight of the
child.
The infant or child restraint must be properly
secured with the vehicle's seat belt, the seat
belt and Top Tether strap, or lower anchors
and Top Tether strap, fully in accordance with
the child seat manufacturer's instructions.
Occupants, especially children, should always
sit as upright as possible, wear the seat belt
properly and use an appropriately sized infant
restraint, toddler restraint, or booster seat
recommended for the size and weight of the
child.
Children can be killed or seriously injured by
an inflating air bag. Note the following
important information when circumstances
require you to place a child in the front-
passenger seat:
R Your vehicle is equipped with air bag
technology designed to deactivate the
front-passenger front air bag in your vehicle
when the system senses the weight of a
typical 12-month-old child or less along
with the weight of a standard appropriate
child restraint on the front-passenger seat.
R Ac hild 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 in a collision which
could occur under some circumstances,
even with the air bag technology installed
in your vehicle. The only means to eliminate
this risk completely is never to place a child
in a rear-facing child restraint in the front-
passenger seat. We therefore strongly
recommend that you always place a child
in a rear-facing child restraint on the rear
seat.
R If you install a rear-facing child restraint on
the front-passenger seat, make sure the
001B001D indicator lamp is illuminated,
indicating that the front-passenger front air
bag is deactivated. Should the 001B001D
indicator lamp not illuminate or go out while
the restraint is installed, please check
installation. Periodically check the 48
Occupant safetySafety

operation is possible using the switches in
the rear compartment.
Driving safety systems
Overview of driving safety systems
In this section, you will find information about
the following driving safety systems:
R ABS (Anti-lock BrakingSystem)
R BAS (Brake AssistSystem)
R BAS PLUS ( BrakeAssist System Plus)
R ESP ®
(Electronic StabilityProgram)
R EBD ( Electronic Brake force Distribution)
R PRE-SAFE ®
Brake 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 asafe 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 note son tires,
recommended minimu mtire tread depths,
etc. (Y page 328).
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 "Importan tsafety notes"
sectio n(Ypage 64). G
WARNING
If ABSi s 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 259) and
display messages which may be shown in the
instrument cluster (Y page 232).
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 001AABS 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 64
Driving safety systemsSafety

R
there are strong rada rreflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in fron tonadifferent line
relative to the center of your vehicle G
WARNING
BAS PLUS does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
As aresult, 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 fron tend of the
vehicle, have the configuratio nand operation
of the rada rsensors checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the fron tofthe vehicle. ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes"
section (Y page 64).
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) i
Observe the "Important safety notes"
section (Y page 64).
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 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.
! When testing the electric parking brake
on a braking dynamometer, switch off the
ignition. Application of the brakes by
ESP ®
may otherwise destroy the brake
system.
Vehicles without 4MATIC: observe the notes
on ESP ®
(Y page 322) when towing the
vehicle with a raised rear axle.
! Vehicles with 4MATIC: function or
performance tests may only be carried out
on a 2-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.
ESP ®
is deactivated if the 0017warning lamp
in the instrumentc luster lights up
continuously when the engine is running. 66
Driving safety systemsSafety

controlled manner. The spinning of the
wheels results in a cutting action, which
provides bette rgrip.
R ESP ®
still provides support when you
brake.
Characteristics when ESP ®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the 000FESP®
warning lamp in
the instrument cluster does not flash. In such
situations, ESP ®
will not stabilize the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R the engine's torque is no longer limited and
the drive wheels are able to spin without
restriction. The spinning of the wheels
results in a cutting action, which provides
better grip.
R traction control is still activated.
R PRE-SAFE ®
Brake is no longer available;
nor is it activated if you brake with
assistance from ESP ®
.
R ESP ®
still provides support when you
brake.
ESP ®
trailer stabilization G
WARNING
If road and weather conditions are poor,
trailer stabilization will not be able to prevent
the vehicle/trailer combination from
swerving. Trailers with a high center of gravity
can tip over before ESP ®
can detect this.
There is a risk of an accident.
Always adapt yourd riving style to the
prevailing road and weather conditions.
If yourv ehicle with trailer (vehicle/trailer
combination) begins to lurch, you can only
stabilize the vehicle/trailer combination by
depressing the brake firmly.
In this situation, ESP ®
assists you and can
detec tifthe vehicle/trailer combination
begins to lurch. ESP ®
slows the vehicle down
by braking and limiting the engine output until the vehicle/trailer combination has
stabilized.
Trailer stabilization is active above speeds of
about 40 mph (65 km/h).
Trailer stabilization does not work if ESP
®
is
deactivated because of a malfunction. 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 259) as well as
display messages (Y page 233).
EBD monitors and controls the brake
pressure on the rear wheels to improve
driving stability while braking. PRE-SAFE
®
Brake
i Observe the "Important safety notes"
section (Y page 64).
PRE-SAFE ®
Brake is only available in vehicles
with DISTRONIC PLUS.
If PRE-SAFE ®
Brake is to aid you, the radar
sensor system must be:
R activated (Y page 229)
R operational
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.
PRE-SAFE ®
Brake can help you to minimize
the risk of a collision with a vehicle ahead or Driving safety systems
69Safety Z

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 differen tline
relative to the center of your vehicle G
WARNING
PRE-SAFE ®
Brake does not react:
R to people or 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 order to maintain an appropriate distance
from the vehicle in front and thus prevent a
collision, you must apply the brakes yourself.
X To activate/deactivate: activate or
deactivate PRE-SAFE ®
Brake in the on-
board computer (Y page 225).
When PRE-SAFE ®
Brake is activated, the
0001 symbol appears in the multifunction
display as long as the HOLD function is
deactivated (Y page 179).
On vehicles with Parking Guidance, the
0001 symbol is displayed when position P
is engaged or you are driving faster than
22 mph (35 km/h).
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. Theft deterrent locking system
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
SmartKey that is left inside the vehicle.
X To activate with the SmartKey: remove
the SmartKey from the ignition lock.
X To activate with KEYLESS-GO: switch the
ignition off and open the driver's door.
X To deactivate: switch on the ignition.
i The immobilizer is always deactivated
when you start the engine.
In the event that the engine cannot be
started when the starter battery is fully
charged, the immobilizer may be faulty.
Contact an authorized Mercedes-Benz
Center or call 1-800-FOR-MERCedes (in the
USA) or 1-800-387-0100 (in Canada). ATA (anti-theft alarm system)
Av isual and audible alarm is triggered if the
alarm system is armed and you open:
R a door
R the vehicle with the mechanical key
R the tailgate
R the hood
The alarm is not switched off, even if you
close the open door that triggered it, for
example. Theft deterrent locking system
71Safety Z

0002
000B To lock the vehicle
0003 0004 To open/close the tailgate
0021 000C To unlock the vehicle
The turn signals flash once when unlocking
and three times when locking.
When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 227).
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 (Y page 228).
X To unlock centrally: press the000C
button.
If you do not open the vehicle within
approximately 40 seconds of unlocking:
R the vehicle is locked again.
R the theft deterren tlocking system is armed
again.
X To lock centrally: press the000Bbutton. KEYLESS-GO
General notes Bear in mind that the engine can be started
by any of the vehicle occupants if there is a
KEYLESS-GO key in the vehicle.
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 functions of KEYLESS-GO with those of a
conventional SmartKey. Unlock the vehicle
by using KEYLESS-GO, for instance, and lock
it using the
000Bbutton on the SmartKey.
When locking or unlockin gwith 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:
R when the external door handles are
touched
R when starting the engine
R while the vehicle is in motion X
To unlock the vehicle: touch the inner
surface of the door handle.
X To lock the vehicle: touch sensor
surface 0002.
X Convenience closing feature: touch
recessed sensor surface 0003for an
extended period.
Further information on the convenience
closing feature (Y page 88).
If you pull on the handle of the tailgate, only
the cargo compartment of the vehicle is
unlocked. Changing the settings of the locking
system
You can change the settings of the locking
system. This means that only the driver's door SmartKey
75Opening and closing Z

Problem Possible causes/consequences and
0001 Solutions
You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. The engine cannot be
started using the
SmartKey. The on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 314).
or
X Jump-start the vehicle (Y page 318).
or
X Consult a qualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. Ad
oor is open. Therefore, the SmartKey cannot be detected as
easily.
X Close the door and try to start the vehicle again. There is interference from a powerful source of radio waves.
X
Start your vehicle with the SmartKey in the ignition lock. Doors
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle. Unlocking and opening doors from
the inside
You can open a door from inside the vehicle
even if it has been locked. You can only open
the rear doors from inside the vehicle if they
are not secured by the child-proof locks
(Y page 63).
Only open the door when the traffic situation
permits. Doors
79Opening and closing Z