
Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
which was available at the time of
purchase. Country-specific differences are
possible. Bear in mind that your vehicle
may not feature all functions described
here. This also refers to safety-related
systems and functions.
Occupant safety
Overview of occupant safety
In this section you will learn the most
important facts about the restraint system
components of the vehicle.
The restraint systems are:
R Seat belts
R Child restraint systems
R "LATCH" type child seat mountings
Additional protection is provided by:
R SRS (Supplemental Restraint System)
R NECK-PRO head restraints
R PRE-SAFE ®
R Air bag system components with:
- PASSENGER air bag OFF indicator lamp
- USA only: front-passenger seat with
Occupant Classification System (OCS)
- Canada only: front-passenger seat with
BabySmart™ air bag deactivation system
The protective functions of the systems work
in conjunction with each other. The systems
are, however, autonomous.
GWarning!
Modifications to or work improperly
conducted on restraint system components
or their wiring, as well as tampering with
interconnected electronic systems, can lead
to the restraint systems no longer functioning
as intended.
Air bags or Emergency Tensioning Devices/
belt buckle tensioners, for example, could
deploy inadvertently or fail to deploy.
Therefore, never modify the restraint
systems. Do not tamper with electronic
components or their software.
i More information on the subject of
children in the vehicle and child restraint
systems can be found under the "Children
in the vehicle" chapter ( Y page 58).
SRS (Supplemental Restraint System)
Introduction
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 consists of:
R + SRS warning lamp
R air bags
R air bag control unit (with crash sensors)
R ETDs/belt buckle tensioners
R belt force limiters
SRS warning lamps
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 + 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 + indicator lamp goes
out while the engine is running.
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Window curtain air bags : are deployed:
R on the side on which an impact occurs
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
R regardless of whether the front-passenger
seat is occupied
R if the vehicle overturns and the system
determines that window curtain air bag
deployment can offer additional protection
to that provided by the seat belt
R independently of the front air bags
The window curtain air bags will not deploy in
impacts which do not exceed the system's
preset thresholds. You will then be protected
by the fastened seat belts.
Occupant classification system (OCS)
Operating principles of the Occupant
Classification System
The OCS is standard equipment in the USA.
OCS categorizes the occupant on the front-
passenger seat by means of a weight sensor.
The front-passenger front air bag is
automatically deactivated for certain weight
categories. The 42 indicator
lamp shows you the current status. If the
42 indicator lamp lights up, the
front-passenger front air bag is deactivated.
The system does not disable:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Device/belt
buckle tensioner (ETD)
To be classified correctly, the front passenger
must sit:
R with the seat belt properly fastened
R in a position that is as upright as possible
with the back against the seat backrest
R with their feet on the floor
The OCS weight sensor is distorted if the
occupant's weight is transferred to another
object in the vehicle, e.g. by leaning on the
armrest.
In addition, the occupant weight may appear
to increase or decrease due to the following:
R objects hanging on the seat
R objects lodged underneath the seat
R objects lodged between the seat and the
center console
R objects lodged between the seat and the
door
R other passengers exerting weight on the
seat
R objects applying pressure to the back of
the seat
Make sure that the seat always has clearance
in all directions.
If the front-passenger seat, the seat cover or
the seat cushion are damaged, have the
necessary repair work carried out at an
authorized Mercedes-Benz Center.
For safety reasons, Mercedes-Benz
recommends that you only use seat
accessories which have been approved by
Mercedes-Benz.
Both the driver and the front passenger
should observe the 42 indicator
lamp to determine whether or not the front
passenger is positioned correctly.42Occupant safetySafety
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complete accordance with the child seat
manufacturer's instructions.
Occupants, in particular children, must sit as
upright as possible, fasten the seat belt
correctly and use a suitable infant restraint
system, child restraint system or booster seat
suitable for the size and weight of the child.
Children can be killed or seriously injured by
an inflating air bag. Observe the following
important information if it is absolutely
necessary to carry a child on the front-
passenger seat:
R your vehicle is equipped with air bag
technology designed to deactivate the
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 passenger seat.
R a child in a rear-facing child restraint on the
passenger seat will be seriously injured or
even killed if the 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 way to completely rule out this risk
is by making sure you never place a child in
a rearward-facing child restraint system on
the front-passenger seat. For this reason,
we strongly advise that you always carry
children in a rearward-facing child restraint
system on a rear seat.
R if it is absolutely necessary to install a
rearward-facing child restraint system on
the front-passenger seat, make sure the
42 indicator lamp is
illuminated, indicating that the front-
passenger front air bag is disabled. If the
42 indicator lamp does not
light up or goes out when the child restraint
system is installed, check the anchorages
of the restraint system. Check the
42 indicator lamp regularly
while driving to ensure that the
42 indicator lamp is
illuminated. If the 42 indicatorlamp lights up or remains out, you may only
carry a child on the front-passenger seat
once the system has been repaired.
A child in a rear-facing child restraint on the
passenger seat will be seriously injured or
even killed if the passenger front air bag
inflates.
R when securing a child in a child restraint
system on the front-passenger seat, you
must:
- move the front-passenger seat as far
back as possible
- use a child restraint system that is
suitable for the age, size and weight of
the child
- observe the manufacturer's installation
instructions in order to install and secure
the child restraint system correctly.
R for children larger than the typical 12-
month-old child, the passenger front air bag
is activated.
Deployment of the driver front air bag does
not mean that the front-passenger front air
bag also should have deployed. The OCS may
have determined:
R that the seat was empty or occupied by a
person with a weight up to or less than that
of a typical 12 month-old child seated in a
standard child restraint
R that the seat was occupied by a small
person (e.g. a young teenager or a small
adult) or a child that weighs more than a
typical 12 month old child in a child
restraint system
These are examples of when OCS disables the
front-passenger front air bag. This occurs
even though the impact fulfills the criteria for
deployment of the driver's front air bag.44Occupant safetySafety
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Belt warning for 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 once the driver and
the front passenger have fastened their seat
belts.
If the driver's seat belt is not fastened after
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:
R the 7 seat belt warning lamp remains
illuminated as long as either the driver's or
front-passenger seat belt is not fastened.
R if the vehicle speed once exceeds 15 mph
(25 km/h), the 7 seat belt warning
lamp lights up. Additionally, a warning tone
will sound with increasing intensity for a
maximum of 60 seconds or until the
driver's and front-passenger seat belt are
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 even if the driver or
front passenger have still not fastened their
seat belt after 60 seconds. The 7 seat belt
warning lamp stops flashing but continues to
be illuminated.
After the vehicle has come to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed has exceeded 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 "Indicator and
warning lamps in the instrument cluster,
seat belt" ( Y page 248).
Emergency Tensioning Devices and
seat belt force limiters
The front seat belts and the outer seat belts
in the rear are equipped with ETDs and belt
force limiters. In addition, the front seat belts
are installed with belt buckle tensioners.
! 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
Tensioning Device/belt buckle tensioner
could be triggered in the event of an
accident.
ETDs/belt buckle tensioners tighten the seat
belts in an accident, pulling them close
against the body.
ETDs/belt buckle tensioners do not correct
incorrect seat positions or incorrectly
fastened seat belts.
ETDs do not pull vehicle occupants back
towards the backrest.
Seat belt force limiters, when activated, are
employed to help reduce the force exerted by
the seat belts on occupants during a crash.
The front belt force limiters are synchronized
with the front air bags, which take on a part
of the deceleration force. Thus, the force
exerted on the occupant is distributed over a
greater area.
The ETDs/belt buckle tensioners can only be
activated when:
R the ignition is switched on
R the restraint systems are operational; see
"SRS warning lamp" ( Y page 36)
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Rthe belt tongue is engaged in the buckle on
each of the three-point seat belts in the
front
R the front-passenger seat is occupied and
the belt tongue is engaged in the buckle on
the front-passenger side.
The ETDs on the outside seats in the rear
compartment are triggered independently of
the lock status of the seat belts.
The ETDs are triggered depending on the type
and severity of an accident:
R in the event of a head-on or rear-end
collision if the vehicle decelerates or
accelerates rapidly in a longitudinal
direction during the initial stages of the
impact
R in the event of a side impact, on the side
opposite the impact if the vehicle
decelerates or accelerates rapidly in a
lateral direction
R in certain situations if the vehicle overturns
and the system determines that it can
provide additional protection.
If the ETDs/belt buckle tensioners are
triggered, you will hear a bang and a small
amount of powder may also be released. Only
in rare cases will the bang affect your hearing.
The powder that is released generally does
not constitute a health hazard. The + SRS
warning lamp lights up.
i If the belt buckle tensioners have been
triggered on the front seats, the buckle will
be pulled down and will be almost flush with
the upper edge of the seat. The + SRS
warning lamp is lit.GWarning
The belt buckle tensioners on the front seats
only function if the belt buckles can be pulled
down unobstructed. They must not be
restricted in any way. Therefore, do not grab
the belt buckles and do not place any objects
under the belt buckles. Otherwise, the
tensioning of the belt by the buckle is
restricted or will not function, and will not
provide any additional protection.
GWarning
Pyrotechnical ETDs/belt buckle tensioners
that were activated must be replaced.
For your safety, when disposing of the
pyrotechnic ETDs/belt buckle tensioners
always follow our safety instructions. These
instructions are available from any authorized
Mercedes-Benz Center.
The PRE-SAFE ®
system is equipped with
electrically reversible pre-tensioners that do
not need replacing after deployment.
Children in the vehicle
Important safety guidelines
GWarning
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unattended in the
vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could:
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
ignition lock or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and the child could be burned on these
parts.
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2. This device must withstand any
interference received, including
interference that may cause undesired
operation of the device.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
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 Braking System)
R BAS ( Brake Assist System)
R ESP ®
(E lectronic Stability Program)
R EBD ( Electronic Brake-power Distribution)
Important safety guidelines
GWarning
The following factors increase the risk of
accidents:
R Excessive speed, especially in turns
R Wet and slippery road surfaces
R Following another vehicle too closely
The driving safety systems described in this
section cannot reduce these risks or prevent
the natural laws of physics from acting on the
vehicle. They cannot increase braking or
steering efficiency beyond that afforded by
the condition of the vehicle brakes and tires
or the traction afforded.
Only a safe, attentive, and skillful driver can
prevent accidents.
The capabilities of a vehicle equipped with the
driving safety systems described in this
section must never be exploited in a reckless
or dangerous manner which could jeopardize
the user's safety or the safety of others.
Always adjust your driving style to the
prevailing road and weather conditions and
keep a safe distance to other road users and
objects on the street.
If a driving system malfunctions, other driving
safety systems may also switch off. Observe
indicator and warning lamps that may come
on as well as messages in the multifunction
display that may appear.GWarning!
HYBRID vehicles: It is imperative that you read
the HYBRID Supplemental Operating
Instructions included in your vehicle literature
portfolio. You may otherwise not receive all
necessary safety information and warning for
the operation of your vehicle.
i 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 information
GWarning
Observe "Important safety instructions"
( Y page 65).
GWarning!
Do not pump the brake pedal. Use firm, steady
brake pedal pressure instead. Pumping the
brake pedal reduces the braking effect.
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 when you only brake gently.
The ! warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
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Rtraction control is still activated.
R ESP ®
still provides support when you
brake.
If ESP ®
is deactivated and one or more wheels
start to spin, the d warning lamp in the
instrument cluster flashes. In such situations,
ESP ®
will not stabilize the vehicle.XTo deactivate: press button :.
The d warning lamp in the instrument
cluster lights up.GWarning
When the d ESP®
warning lamp is
illuminated continuously, the ESP ®
is
switched off or is not operational due to a
malfunction. Vehicle stability in standard
driving maneuvers is reduced.
Adapt your speed and driving style to the
prevailing road conditions and to the non-
operating status of the ESP ®
.
! Avoid spinning a drive wheel for an
extended period with ESP switched off. This
could cause serious damage to the drive
train.
XTo activate: press button :.
The d warning lamp in the instrument
cluster goes out.
Off-road ESP ®
An ESP
®
system specifically suited to off-road
terrain is activated automatically once the off-
road drive program (Y page 193) is activated.
It intervenes with a delay if there is
oversteering or understeering, thus
improving traction.
ESP ®
trailer stabilization
If your trailer begins to lurch, you can only
stabilize the vehicle/trailer combination by
depressing the brake firmly.
In this situation, ESP ®
assists you and can
detect if the trailer 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 from a speed
above 40 mph (65 km/h).
GWarning!
The system will not be able to assist when the
trailer jackknifes
R if the ESP ®
has switched off due to a
malfunction
R on wet or icy roads
R on roads with slippery surface
R in sand or gravel
Trailers with a high center of gravity may tip
over before the system recognizes swaying of
the trailer.
Trailer stabilization does not work if ESP ®
is
deactivated or disabled because of a
malfunction.
EBD
GWarning
Observe "Important safety instructions"
( Y page 65).
EBD monitors and controls the brake
pressure on the rear wheels to improve
driving stability while braking.
GWarning!
If the EBD malfunctions, the brake system will
still function with full brake boost. However,
the rear wheels could lock up during
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GWarning
Batteries contain toxic and caustic
substances. For this reason, keep batteries
out of the reach of children.
If a battery has been swallowed, seek medical
help immediately.
GWarning
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Observe
government disposal guidelines. California
residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Checking the battery
XPress the & or % button.
The SmartKey battery is working properly if
battery charge indicator lamp : lights up
briefly.
If battery charge indicator lamp : does not
light up briefly during the test, the SmartKey
battery is discharged.
XReplace the SmartKey battery
( Y page 76).
i
You can obtain a SmartKey battery at any
authorized Mercedes-Benz Center.
i If the SmartKey battery is checked within
signal range of the vehicle, pressing the
& or % button results in the vehicle
being locked or unlocked respectively.
Changing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the
SmartKey ( Y page 75).XPress mechanical key ; into the opening
in the SmartKey in the direction of the
arrow until battery tray cover : opens. Do
not hold the cover closed while doing so.XRemove the cover of the battery tray.XRepeatedly tap the SmartKey against your
palm until battery = falls out.XInsert the new battery with the positive
pole facing upwards. Use a lint-free cloth to
do so.XInsert the front tabs of the battery tray's
cover first and then press to close it.XCheck the function of all SmartKey buttons
on the vehicle.76SmartKeyOpening and closing
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