Seat belts
Introduction
Seat belts are the most effective means of
restricting the movement of vehicle occupants
in the event of an accident or the vehicle rolling over. This reduces the risk of vehicle occupants
coming into contact with parts of the vehicle
interior or being ejected from the vehicle. Fur-
thermore, the seat belt helps to keep the vehicle
occupant in the best position in relation to the
air bag.
The seat belt system comprises:
RSeat belts
REmergency Tensioning Devices for the front
seat belts and the outer seat belts in the rear
RSeat belt force limiters
If the seat belt is pulled out of the belt outlet
quickly or with a jerky movement, the belt
retractor locks. The belt strap cannot be extrac-
ted any further.
The Emergency Tensioning Device tightens the
seat belt in an accident, pulling the belt close
against the body. However it does not pull the
vehicle occupant back in the direction of the
backrest.
The Emergency Tensioning Device does not cor-
rect an incorrect seat position or the routing of
an incorrectly fastened seat belt.
When triggered, a seat belt force limiter helps to
reduce the force exerted by the seat belt on the
vehicle occupant.
The seat belt force limiters for the front seats are
synchronized with the front air bags, which
absorb part of the deceleration force. This can
reduce the force exerted on the vehicle occu-
pants during an accident.
!If the front-passenger seat is unoccupied,
do not insert the belt tongue into the buckle of
the front-passenger seat. This may otherwise
lead to the triggering of the Emergency Ten-
sioning Device in the event of an accident,
which will then need to be replaced.
Important safety notes
The use of seat belts and child restraint systems
is required by law in:
Rall 50 states
Rthe U.S. territories
Rthe District of Columbia
Rall Canadian provinces
Even where this is not required by law, all vehicle
occupants should correctly fasten their seat
belts before starting the journey.
GWARNING
If the seat belt is incorrectly fastened, it can-
not protect as intended. Furthermore, an
incorrectly fastened seat belt can cause addi-
tional injury, for example, in an accident, dur-
ing braking or when abruptly changing direc-
tion. This poses an increased risk of injury or
even fatal injury.
Make sure that all vehicle occupants are
seated properly with a correctly fastened seat belt.
GWARNING
The seat belt does not offer the intended level of protection if you have not moved the back-
rest to an almost vertical position. When brak-
ing 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 ensure that the backrest
is in an almost vertical position and that the
shoulder section of your seat belt is routed
across the center of your shoulder.
GWARNING
Persons under 5 ft (1.50 m) in height cannot
fasten the seat belt correctly without an addi- tional suitable restraint system. If the seat
belt is incorrectly fastened, it cannot protect
as intended. Furthermore, an incorrectly fas-
tened seat belt can cause additional injury, for
example, in an accident, during braking or an
abrupt change of direction. This poses an
increased risk of injury or even fatal injury.
For this reason, always secure persons under
5 ft (1.50 m) in height in suitable restraint
systems.
40Occupant safety
Safety
The system does not deactivate:
Rthe side impact air bag
Rthe window curtain air bag
Rthe Emergency Tensioning Devices
In the following situation, the side impact air bag and the Emergency Tensioning Device are deac-
tivated:
ROCS has not categorized the person on the
front-passenger seat as an adult or a person
of corresponding stature and
Rthe seat belt tongue of the seat belt is not
inserted into the front-passenger seat belt
buckle
Prerequisites
To be classified correctly, the front passenger
must sit:
Rwith the seat belt fastened correctly
Rin an almost upright position with their back
against the seat backrest
Rwith their feet resting on the floor, if possible
If the front passenger does not observe these
conditions, OCS may produce a false classifica-
tion, e.g. because the front passenger:
Rtransfers their weight by supporting them-
selves on a vehicle armrest
Rsits in such a way that their weight is raised
from the seat cushion
If it is absolutely necessary to install a child
restraint system on the front-passenger seat, be
sure to observe the correct positioning of the
child restraint system. Never place objects
under or behind the child restraint system, e.g.
cushions. The entire base of the child restraint
system must always rest on the seat cushion of the front-passenger seat. The backrest of the
forward-facing child restraint system must lie as
flat as possible against the backrest of the front-
passenger seat.
The child restraint system must not touch the
roof or be subjected to a load by the head
restraint. Adjust the angle of the seat backrest
and the head restraint position accordingly.
Only then can OCS be guaranteed to function
correctly. Always observe the child restraint sys-
tem manufacturer's installation instructions.
Occupant Classification System opera-
tion (OCS)
:PASSENGER AIR BAG ON indicator lamp
;PASSENGER AIR BAG OFF indicator lamp
The indicator lamps indicate whether the front-
passenger front air bag is activated or deactiva- ted.
XPress the start/stop button once or twice, or
turn the SmartKey to position 1or 2in the
ignition lock.
The system carries out a self-diagnosis test.
The PASSENGER AIR BAG OFF and PASSENGER
AIR BAG ON indicator lamps must light up simul-
taneously for about six seconds.
The indicator lamps then display the status of
the front-passenger front air bag:
RPASSENGER AIRBAG ON lights up: the front-
passenger front airbag is enabled. If, in the
case of an accident, all deployment criteria
are met, the front-passenger front air bag is
deployed.
RPASSENGER AIRBAG OFF lights up: the front-
passenger front airbag is disabled. It will then
not be deployed in the event of an accident.
If the status of the front-passenger front air bag changes whilst the vehicle is in motion, an air
bag display message may appear in the instru-
ment cluster (
Ypage 244). Always observe the
PASSENGER AIR BAG ON and PASSENGER AIR
BAG OFF indicator lamps when the front-
passenger seat is occupied. Make sure that the
status of the front-passenger front air bag is
correct before and during a journey.
GWARNING
If the PASSENGER AIR BAG OFF indicator
lamp is lit, the front-passenger front air bag is
disabled. It will not be deployed in the event of
an accident and cannot perform its intended
46Occupant safety
Safety
Have the vehicle towed to a qualified special-
ist workshop in order to have a deployed air
bag replaced.
It is important for your safety and that of your
passenger to have deployed air bags replaced
and to have any malfunctioning air bags
repaired. This will help to make sure the air bags
continue to perform their protective function for
the vehicle occupants in the event of a crash.
GWARNING
Pyrotechnic Emergency Tensioning Devices
that have been deployed are no longer opera-
tional and are unable to perform their inten-
ded protective function. This poses an
increased risk of injury or even fatal injury.
Therefore, have pyrotechnic Emergency Ten-
sioning Devices which have been triggered
immediately replaced at a qualified specialist workshop.
An electric motor is used by PRE-SAFE
®to trig-
ger the tightening of the seat belt in hazardous
situations. This procedure is reversible.
If Emergency Tensioning Devices are triggered
or air bags are deployed, you will hear a bang,
and a small amount of powder may also be
released. The 6restraint system warning
lamp lights up.
Only in rare cases will the bang affect your hear-
ing. The powder that is released generally does
not constitute a health hazard, but it may cause
short-term breathing difficulties in people with
asthma or other respiratory problems. Provided
it is safe to do so, you should leave the vehicle
immediately or open the window in order to pre-
vent breathing difficulties.
Air bags and pyrotechnic Emergency Tensioning
Devices (ETDs) contain perchlorate material,
which may require special handling and regard
for the environment. National guidelines must
be observed during disposal. In California, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm.
Method of operation
During the first stage of a collision, the restraint
system control unit evaluates important physi-
cal data relating to vehicle deceleration or accel-
eration, such as:
Rduration
Rdirection
Rintensity
Based on the evaluation of this data, the
restraint system control unit triggers the Emer-
gency Tensioning Devices during a frontal or
rear collision.
An Emergency Tensioning Device can only be
triggered, if:
Rthe ignition is switched on
Rthe components of the restraint system are
operational. You can find further information
under: "Restraint system warning lamp"
(
Ypage 39)
Rthe belt tongue is engaged in the buckle on
the respective front-passenger seat
The Emergency Tensioning Devices in the rear
compartment are triggered independently of the
lock status of the seat belts.
If the restraint system control unit detects a
more severe accident, further components of
the restraint system are activated independ-
ently of each other in certain frontal collision
situations:
RFront air bags and driver's knee bag
RWindow curtain air bag, if the system deter-
mines that deployment can offer additional
protection to that provided by the seat belt
The front-passenger front air bag is activated or
deactivated depending on the person on the
front-passenger seat. The front-passenger front
air bag can only deploy in an accident if the
PASSENGER AIR BAG ON indicator lamp is lit.
Observe the information on the PASSENGER AIR
BAG indicator lamps (
Ypage 39).
Your vehicle has two-stage front air bags. During the first d
eployment stage, the front air bag is
filled with propellant gas to reduce the risk of
injuries. The front air bag is fully deployed with
the maximum amount of propellant gas if a sec-
ond deployment threshold is reached within a
few milliseconds.
The activation threshold of the Emergency Ten-
sioning Devices and the air bag are determined
by evaluating the rate of vehicle deceleration or
acceleration which occurs at various points in
Occupant safety51
Safety
Z
PRE-SAFE®takes the following measures
depending on the hazardous situation detected:
Rthe front seat belts are pre-tensioned.
Rif the vehicle skids, the side windows and the
sliding sunroof are closed.
Rvehicles with the memory function: the front-
passenger seat is adjusted if it is in an unfav-
orable position.
Rvehicles with a multicontour seat: the air pres-
sure in the side bolsters of the seat backrest
is increased.
If the hazardous situation passes without result-
ing in an accident, PRE-SAFE
®slackens the belt
pre-tensioning. On vehicles with multicontour
seats, the air pressure in the side bolsters is
reduced again. All settings made by PRE-SAFE
®
can then be reversed.
If the seat belt pre-tensioning is not reduced:
XMove the seat backrest or seat back slightly
when the vehicle is stationary.
The seat belt pre-tensioning is reduced and
the locking mechanism is released.
The seat-belt adjustment is an integral part of
the PRE-SAFE
®convenience function. Informa-
tion about the convenience function can be
found under "Belt adjustment" (
Ypage 42).
PRE-SAFE®PLUS (anticipatory occu-
pant protection system PLUS)
Introduction
PRE-SAFE®PLUS is only available in vehicles
with the Driving Assistance package.
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 about the intervention
of PRE-SAFE
®PLUS.
PRE-SAFE®PLUS does not intervene if the vehi-
cle is backing up.
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:
Rif the radar sensor system detects that a
head-on collision is imminent, the seat belts
are pre-tensioned.
Rif the radar sensor system detects that a rear-
end collision is imminent:
-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-
celed:
Rif the accelerator pedal is depressed when a
gear is engaged
Rif the risk of a collision passes or is no longer
detected
Rif 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:
Rthe hazard warning lamps are activated
Rthe emergency lighting is activated
Rthe vehicle doors are unlocked
Rthe front side windows are lowered
Rvehicles with a memory function: the electri-
cally adjustable steering wheel is raised
Rthe engine is switched off and the fuel supply
is cut off
Rvehicles with mbrace: automatic emergency
call
Occupant safety53
Safety
Z
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 5 ft (1.50 m) in height is traveling in the
vehicle:
Ralways 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
Rbe sure to observe the instructions and safety
notes in this section in addition to the child
restraint system manufacturer's installation
instructions
Rbe sure to observe the instructions and safetynotes on the "Occupant classification system
(OCS)" (
Ypage 45)
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking position P.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
GWARNING
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.
GWARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Chil-
dren may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight. Pro- tect it with a blanket, for example. If the child
restraint system has been exposed to direct
sunlight, let it cool down before securing the
child in it. Never leave children unattended in
the vehicle.
Always ensure that all vehicle occupants have
their seat belts fastened correctly and are sitting
properly. Particular attention must be paid to
children.
Observe the safety notes on the seat belt
(
Ypage 40 )and the notes on correct use of seat
belts (Ypage 41).
A booster seat may be necessary to achieve
proper seat belt positioning for children over
41 lb s(18 kg) until they reach a height where a
three-point seat belt can be properly fastened
without a booster seat.
Special seat belt retractor
GWARNING
If the seat belt is released while driving, the
child restraint system will no longer be
secured properly. The special seat belt retrac- tor is disabled and the inertia real draws in a
portion of the seat belt. The seat belt cannot
be immediately refastened. There is an
increased risk of injury, possibly even fatal.
Stop the vehicle immediately, paying atten-
tion to road and traffic conditions. Reactivate
the special seat belt retractor and secure the
child restraint system properly.
All seat belts in the vehicle, except the driver's
seat belt, are equipped with a special seat belt
retractor. When activated, the special seat belt
retractor ensures that the seat belt cannot
slacken once the child seat is secured.
54Children in the vehicle
Safety
The securing systems of child restraint systems
are:
Rthe seat belt system
Rthe LATCH-type (ISOFIX) securing rings
Rthe Top Tether anchorages
If it is absolutely necessary to carry a child on
the front-passenger seat, be sure to observe the
information on the "Occupant Classification
System (OCS)" (
Ypage 45). There you will also
find information on deactivating the front-
passenger front air bag.
All child restraint systems must meet the fol-
lowing standards:
RU.S. Federal Motor Vehicle Safety Standards
213 and 225
RCanadian Motor Vehicle Safety Standards
213 and 210.2
Confirmation that the child restraint system cor-
responds to the standards can be found on an
instruction label on the child restraint system.
This confirmation can also be found in the instal-
lation instructions that are included with the
child restraint system.
Observe the warning labels in the vehicle inte-
rior and on the child restraint system.
LATCH-type (ISOFIX) child seat secur-
ing system
GWARNING
LATCH-type (ISOFIX) child restraint systems
do not offer sufficient protective effect for
children whose weight is greater than 48 lbs
(22 kg) who are secured using the safety belt integrated in the child restraint system. In the
event of an accident, a child might not be
restrained correctly. This poses an increased
risk of injury or even fatal injury.
If the child weighs more than 48 lbs (22 kg),
only use LATCH-type (ISOFIX) child restraint
systems with which the child is also secured
with the vehicle seat belt. Also secure the
child restraint system with the Top Tether
belt, if available.
Always comply with the manufacturer's instal-
lation and operating instructions for the child
restraint system used. Before every trip, make sure that the LATCH-
type (ISOFIX) child restraint system is engaged
correctly in both LATCH-type (ISOFIX) securing
rings
!When installing the child restraint system,
make sure that the seat belt for the middle
seat does not get trapped. The seat belt could
otherwise be damaged.
XInstall the LATCH-type (ISOFIX) child restraint system on both LATCH-type (ISOFIX) securing
rings :.
ISOFIX is a standardized securing system for
specially designed child restraint systems on
the rear seats. LATCH-type (ISOFIX) securing
rings for two LATCH-type (ISOFIX) child restraint
systems are installed on the left and right of the
rear seats.
Non-LATCH-type (ISOFIX) child seats may also
be used and can be installed using the vehicle's
seat belt system. Install the child seat according
to the manufacturer's instructions.
Top Tether
Introduction
Top Tether provides an additional connection
between the child restraint system secured with
a LATCH-type (ISOFIX) system and the vehicle.
This helps reduce the risk of injury even further.
If the child restraint system is equipped with a
Top Tether belt, this should always be used.
Important safety notes
GWARNING
If the rear seat backrests are not locked, they
could fold forwards in the event of an acci-
dent, heavy braking or sudden changes of
56Children in the vehicle
Safety
direction. As a result, child restraint systems
cannot perform their intended protective
function. Rear seat backrests that are not
locked can also cause additional injuries, e.g.
in the event of an accident. This poses an
increased risk of injury or even fatal injury.
Always lock rear seat backrests after instal-
ling a Top Tether belt. Adjust the rear seat
backrests so that they are in an upright posi-
tion.
Make sure that the backrest in the rear com-
partment engages fully. To do so, pull firmly on
the seat backrest.
Top Tether anchorages
Top Tether anchorage points ?are located on
the rear side of the rear seat backrests.
XMove head restraint =up (Ypage 97).
XInstall the LATCH-type (ISOFIX) child restraint
system with Top Tether. Always comply with
the child restraint system manufacturer's
installation instructions when doing so.
XRoute Top Tether belt Bunder head restraint
= between the two head restraint bars.
XGuide Top Tether belt Bdownwards between
cargo compartment cover :and rear seat
backrest ;.
XHook Top Tether hook Aof Top Tether belt
B into Top Tether anchorage ?.
Make sure that:
RTop Tether hook Ais hooked into Top
Tether anchorage ?as shown.
RTop Tether belt Bis not twisted.
RTop Tether belt Bis routed between rear
seat backrest ;and cargo compartment
cover :if cargo compartment cover :is
installed.
RTop Tether belt Bis routed between rear
seat backrest ;and the cargo net if the
cargo net is installed.
XTension Top Tether belt B. Always comply
with the child restraint system manufactur-
er's installation instructions when doing so.
XIf necessary, move head restraint =back
down again slightly. Make sure that you do
not interfere with the correct routing of Top
Tether belt B.
Child restraint system on the front-
passenger seat
General 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
the child restraint system on a rear seat.
If it is absolutely necessary to install a child
restraint system on the front-passenger seat,
always observe the instructions and safety
notes on the "Occupant Classification System
(OCS)" (
Ypage 45).
You can thus avoid the risks that could arise as a result of:
Ran incorrectly categorized person in the front-
passenger seat
Rthe unintentional deactivation of the front-
passenger front air bag
Rthe unsuitable positioning of the child
restraint system, e.g. too close to the dash-
board
Children in the vehicle57
Safety
Z
Rearward-facing child restraint system
If it is absolutely necessary to install a rearward-
facing child restraint system on the front-
passenger seat, always make sure that the
front-passenger front air bag is deactivated.
Only if the PASSENGER AIR BAG OFF indicator
lamp is permanently lit (
Ypage 39) is the front-
passenger front air bag deactivated.
Always observe the child restraint system man-
ufacturer's installation and operating instruc-
tions.
Forward-facing child restraint system
If it is absolutely necessary to install a forward-
facing child restraint system on the front-
passenger seat, always move the front-
passenger seat as far back as possible. The
entire base of the child restraint system must
always rest on the seat cushion of the front-
passenger seat. The backrest of the child
restraint system must lie as flat as possible
against the backrest of the front-passenger
seat. The child restraint system must not touch
the roof or be subjected to a load by the head
restraint. Adjust the angle of the seat backrest
and the head restraint position accordingly.
Always make sure that the shoulder belt strap is
correctly routed from the vehicle belt outlet to
the shoulder belt guide on the child restraint
system. The shoulder belt strap must be routed
forwards and downwards from the vehicle belt
outlet. If necessary, adjust the vehicle belt out-
let and the front-passenger seat accordingly.
Always observe the child restraint system man-
ufacturer's installation and operating instruc-
tions.
Child-proof locks
Important safety notes
GWARNING
If children are traveling in the vehicle, they
could:
Ropen doors, thus endangering other people
or road users
Rexit the vehicle and be caught by oncoming
traffic
Roperate vehicle equipment and become
trapped
There is a risk of an accident and injury.
Always activate the child-proof locks and
override feature if children are traveling in the vehicle. When leaving the vehicle, always take
the key with you and lock the vehicle. Never
leave children unattended in the vehicle.
Override feature for:
Rthe rear doors (Ypage 59)
Rthe rear side windows (Ypage 59)
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking position P.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
GWARNING
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.
58Children in the vehicle
Safety