MERCEDES-BENZ GL-Class 2016 X166 Workshop Manual

The shoulder section of the seat belt must
always be routed across the center of the
shoulder. Adjust the belt outlet if necessary.
XTo raise:slide the belt outlet upwards.
The belt outlet will engage in various posi-
tions.
XTo lower: hold belt outlet release :and
slide belt outlet downwards.
XLet go of belt outlet release :in the
desired position and make sure that the
belt outlet engages.
All seat belts except the driver's seat belt are
equipped with a special seat belt retractor to
securely fasten child restraint systems in the
vehicle. Further information can be found
under "Special seat belt retractor"
(
Ypage 61).
Releasing seat belts
!Make sure that the seat belt is fully rolled
up. Otherwise, the seat belt or belt tongue
will be trapped in the door or in the seat
mechanism. This could damage the door,
the door trim panel and the seat belt. Dam-
aged seat belts can no longer fulfill their
protective function and must be replaced.
Visit a qualified specialist workshop.
Basic illustration
XPress release button :, hold belt
tongue ;firmly and guide it back towards
belt outlet =.
Seat belt adjustment
The seat-belt adjustment is an integral part of
the PRE-SAFE®convenience function. This
function adjusts the driver's and front-
passenger seat belt to the upper body of the
occupants.
The belt strap is tightened slightly when:
Rthe belt tongue is engaged in the buckle
and
Rthe ignition is switched on
The seat-belt adjustment will apply a certain
retraction force if any slack is detected
between the vehicle occupant and the seat
belt. Do not hold on to the seat belt tightly
while it is adjusting.
You can switch the seat-belt adjustment on
and off in the on-board computer
(
Ypage 286).
Belt warning for the driver and front
passenger
The 7 seat belt warning lamp in the instru-
ment cluster is a reminder that all vehicle
occupants must wear their seat belts. It may
Occupant safety49
Safety
Z

light up continuously or flash. In addition,
there may be a warning tone.
Regardless of whether the driver's seat belt
has already been fastened, the7seat belt
warning lamp lights up for six seconds each
time the engine is started. If, after
six seconds, the driver or front-passenger
seat belt has not been fastened and the doors
are closed, the 7seat belt warning lamp
lights up. As soon as the driver's and front-
passenger seat belts are fastened or a front
door is opened again, the 7seat belt
warning lamp goes out.
If the driver's seat belt is not fastened after
the engine is started, an additional warning
tone will sound. This warning tone stops after
six seconds or when the driver's seat belt is
fastened.
If the vehicle's speed exceeds 15 mph
(25 km/h) once and the driver's and front-
passenger seat belts are not fastened, a
warning tone sounds. A warning tone also
sounds with increasing intensity for
60 seconds or until the driver or front
passenger have fastened their seat belts.
If the driver or front passenger unfasten their
seat belts during the journey, the seat belt
warning is activated again.
iFor more information on the 7seat
belt warning lamp, see "Warning and indi-
cator lamps in the instrument cluster, seat
belts" (
Ypage 325).
Air bags
Introduction
The installation point of an air bag can be rec- ognized by the AIR BAG symbol.
An air bag complements the correctly fas-
tened seat belt. It is no substitute for the seat
belt. The air bag provides additional protec-
tion in applicable accident situations.
Not all air bags are deployed in an accident.
The different air bag systems function inde-
pendently from one another (
Ypage 58). However, no system available today can com-
pletely eliminate injuries and fatalities.
It is also not possible to rule out a risk of injury
caused by an air bag due to the high speed at
which the air bag must be deployed.
Important safety notes
GWARNING
If you do not sit in the correct seat position,
the air bag cannot protect as intended and
could even cause additional injury when
deployed. This poses an increased risk of
injury or even fatal injury.
To avoid hazardous situations, always make
sure that all of the vehicle's occupants:
Rhave fastened their seat belts correctly,
including pregnant women
Rare sitting correctly and maintain the great-
est possible distance to the air bags
Rfollow the following instructions
Always make sure that there are no objects
between the air bag and the vehicle's occu-
pants.
RAdjust the seats properly before beginning
your journey. Always make sure that the
seat is in an almost upright position. The
center of the head restraint must support
the head at about eye level.
RMove the driver's and front-passenger
seats as far back as possible. The driver's
seat position must allow the vehicle to be
driven safely.
ROnly hold the steering wheel on the out-
side. This allows the air bag to be fully
deployed.
RAlways lean against the backrest while driv-
ing. Do not lean forwards or lean against
the door or side window. You may other-
wise be in the deployment area of the air
bags.
RAlways keep your feet in the footwell in
front of the seat. Do not put your feet on the
dashboard, for example. Your feet may oth-
50Occupant safety
Safety

erwise be in the deployment area of the air
bag.
RFor this reason, always secure persons less
than 5 ft (1.50 m) tall in suitable restraint
systems. Up to this height, the seat belt
cannot be worn correctly.
If a child is traveling in your vehicle, also
observe the following notes:
RAlways secure children under twelve years
of age and less than 5 ft (1.50 m) tall in
suitable child restraint systems.
RChild restraint systems should be installed on the rear seats.
ROnly secure a child in a rearward-facing
child restraint system on the front-
passenger seat when the front-passenger
front air bag is deactivated. If the
PASSENGER AIR BAG OFF indicator lamp ispermanently lit, the front-passenger front
air bag is deactivated (
Ypage 45).
RAlways observe the instructions and safetynotes on the "Occupant Classification Sys-
tem (OCS)" (
Ypage 53) and on "Children
in the vehicle" (
Ypage 61) in addition to
the child restraint system manufacturer's
installation instructions.
Objects in the vehicle interior may pre-
vent an air bag from functioning correctly.
Before starting your journey and to avoid risks
resulting from the speed of the air bag as it
deploys, make sure that:
Rthere are no people, animals or objects
between the vehicle occupants and an air
bag.
Rthere are no objects between the seat, door
and B-pillar.
Rno hard objects, e.g. coat hangers, hang on
the grab handles or coat hooks.
Rno accessories, such as cup holders, are
attached to the vehicle within the deploy-
ment area of an air bag, e.g. to doors, side
windows, rear side trim or side walls.
Rno heavy, sharp-edged or fragile objects
are in the pockets of your clothing. Store
such objects in a suitable place.
GWARNING
If you modify the air bag cover or affix objects
such as stickers to it, the air bag can no longer
function correctly. There is an increased risk
of injury.
Never modify an air bag cover or affix objects
to it.
GWARNING
Sensors to control the air bags are located in
the doors. Modifications or work not per-
formed correctly to the doors or door panel-
ing, as well as damaged doors, can lead to the
function of the sensors being impaired. The air
bags might therefore not function properly
anymore. Consequently, the air bags cannot
protect vehicle occupants as they are
designed to do. There is an increased risk of
injury.
Never modify the doors or parts of the doors.
Always have work on the doors or door pan-
eling carried out at a qualified specialist work-
shop.
Front air bags
Driver's air bag :deploys in front of the
steering wheel. Front-passenger front air
bag ;deploys in front of and above the glove
box.
When deployed, the front air bags offer addi-
tional head and thorax protection for the
occupants in the front seats.
The PASSENGER AIR BAG OFF indicator lamp
informs you about the status of the front-
passenger front air bag (
Ypage 45).
Occupant safety51
Safety
Z

The front-passenger front air bag will only
deploy if:
Rthe system, based on the OCS weight sen-
sor readings, detects that the front-
passenger seat is occupied (
Ypage 53)
Rthe PASSENGER AIR BAG OFF indicator
lamp is not lit (
Ypage 54)
Rthe restraint system control unit predicts a
high accident severity
Driver's knee bag
Driver's knee bag :deploys under the steer-
ing column. The driver's knee bag is triggered
together with the front air bag.
The driver's knee bag offers additional thigh,
knee and lower leg protection for the occu-
pant in the driver's seat.
Side impact air bags
GWARNING
Unsuitable seat covers could restrict or even
prevent the deployment of the air bags inte-
grated into the seats. Consequently, the air
bags cannot protect vehicle occupants as
they are designed to do. In addition, the func- tion of the Occupant Classification System
(OCS) could be restricted. This poses an
increased risk of injury or even fatal injury.
You should only use seat covers that have
been approved for the respective seat by
Mercedes-Benz.
Front side impact air bags :and second row
rear side impact air bags ;deploy next to
the outer bolster of the seat backrest.
When deployed, the side impact air bag offers
additional thorax protection. It also offers
additional pelvis protection for occupants in
the front seats. However, it does not protect
the:
Rhead
Rneck
Rarms
In the event of a side impact, the side impact
air bag is deployed on the side on which the
impact occurs.
The side impact air bag on the front-
passenger side (front) deploys under the fol-
lowing conditions:
Rthe OCS system detects that the front-
passenger seat is occupied or
Rthe belt tongue is engaged in the belt
buckle of the front-passenger seat
If the belt tongue is engaged in the belt
buckle, the side impact air bag on the front-
passenger side deploys if an appropriate acci- dent situation occurs. In this case, deploy-
ment is independent of whether the front-
passenger seat is occupied or not.
52Occupant safety
Safety

Window curtain air bags
Window curtain air bags:are integrated
into the side of the roof frame and deploy in
the area extending from the front door (A-pil-
lar) to the rear side window (D-pillar).
When deployed, the window curtain air bag
enhances the level of protection for the head.
However, it does not protect the chest or
arms.
In the event of a side impact, the window cur-
tain air bag is deployed on the side on which
the impact occurs.
If the system determines that they can offer
additional protection to that provided by the
seat belt, a window curtain air bag may be
deployed in other accident situations
(
Ypage 58).
Occupant Classification System
(OCS)
Introduction
The Occupant Classification System (OCS)
categorizes the person in the front-passenger
seat. Depending on that result, the front-
passenger front air bag is either enabled or
deactivated.
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 deactivated:
ROCS has not categorized the person on the
front-passenger seat as an adult or a per-
son 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 possi-
ble
If the front passenger does not observe these
conditions, OCS may produce a false classi-
fication, 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 theroof or be subjected to a load by the head
restraint. Adjust the angle of the seat back-
rest and the head restraint position accord-
ingly.
Only then can OCS be guaranteed to function
correctly. Always observe the child restraint
system manufacturer's installation instruc-
tions.
Occupant safety53
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Z

Occupant Classification System opera-
tion (OCS)
PASSENGER AIR BAG OFF indicator lamp:
shows you whether the front-passenger front
air bag is deactivated.
XTurn the SmartKey to position 1or 2in the
ignition lock or on vehicles with KEYLESS-
GO, press the Start/Stop button once or
twice.
The system carries out self-diagnostics.
The PASSENGER AIR BAG OFF indicator lamp
must light up for approximately six seconds.
The PASSENGER AIR BAG OFF indicator lamp
then displays the status of the front-
passenger front air bag. If the status of the
front-passenger front air bag changes while
the vehicle is in motion, an air bag display
message may appear in the instrument clus-
ter (
Ypage 301). When the front-passenger
seat is occupied, always pay attention to the
PASSENGER AIR BAG OFF indicator lamp. Be
aware of the status of the front-passenger
front air bag both before and during the jour-
ney.
If the PASSENGER AIR BAG OFF indicator
lamp:
Ris lit: the front-passenger front air bag is
deactivated. It will then not be deployed in
the event of an accident.
Rdoes not light up: the front-passenger
front air bag is enabled. If, in the event of an
accident, all deployment criteria are met,
the front-passenger front air bag is
deployed.
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
protective function. A person in the front-
passenger seat could then, for example, come
into contact with the vehicle's interior, espe-
cially if the person is sitting too close to the
dashboard. This poses an increased risk of
injury or even fatal injury.
When the front-passenger seat is occupied,
always ensure that:
Rthe classification of the person in the front- passenger seat is correct and the front-
passenger front air bag is enabled or disa-
bled in accordance with the person in the
front-passenger seat
Rthe front-passenger seat has been moved
back as far back as possible.
Rthe person is seated correctly.
Make sure, both before and during the jour-
ney, that the status of the front-passenger
front air bag is correct.
GWARNING
If you secure a child in a child restraint system on the front-passenger seat and the
PASSENGER AIR BAG OFF indicator lamp is
off, the front-passenger front air bag can
deploy in the event of an accident. The child
could be struck by the air bag. This poses an
increased risk of injury or even fatal injury.
Make sure that the front-passenger front air
bag has been disabled. The PASSENGER AIR
BAG OFF indicator lamp must be lit.
54Occupant safety
Safety

GWARNING
If you secure a child in a forward-facing child
restraint system on the front-passenger seat
and you position the front-passenger seat too close to the dashboard, the child could, in the
event of an accident:
Rcome into contact with the vehicle's inte-
rior if the PASSENGER AIR BAG OFF indi-
cator lamp is lit, for example
Rbe struck by the air bag if the PASSENGER
AIR BAG OFF indicator lamp is off
This poses an increased risk of injury or even
fatal injury.
Move the front-passenger seat as far back as
possible. Always make sure that the shoulder
belt strap is correctly routed from the vehicle
belt sash guide to the shoulder belt guide on
the child restraint system. The shoulder belt
strap must be routed forwards and down-
wards from the vehicle belt sash guide. If nec- essary, adjust the vehicle belt sash guide and
the front-passenger seat accordingly. Always
observe the child restraint system manufac-
turer's installation instructions.
If OCS determines that:
Rthe front-passenger seat is unoccupied, the
PASSENGER AIR BAG OFF indicator lamp
lights up after the system self-test and
remains lit. This indicates that the front-
passenger front air bag is deactivated.
Rthe front-passenger seat is occupied by a
child of up to twelve months old, in a stand-
ard child restraint system, the PASSENGER
AIR BAG OFF indicator lamp lights up after
the system self-test and remains lit. This
indicates that the front-passenger front air
bag is deactivated.
But even in the case of a twelve-month-old
child, in a standard child restraint system,
the PASSENGER AIR BAG OFF indicator
lamp can go out after the system self-test.
This indicates that the front-passenger
front air bag is activated. The result of the
classification is dependent on, among
other factors, the child restraint system and the child's stature. It is recommended
that
you i
nstall the child restraint system on
a suitable rear seat.
Rthe front-passenger seat is occupied by a
person of smaller stature (e.g. a teenager
or small adult), the PASSENGER AIR BAG
OFF indicator lamp lights up and remains lit
after the system self-test depending on the
result of the classification or, alternatively,
goes out.
-If the PASSENGER AIR BAG OFF indicator
lamp is off, move the front-passenger
seat as far back as possible. Alterna-
tively, a person of smaller stature can sit
on a rear seat.
-If the PASSENGER AIR BAG OFF indicator
lamp is lit, a person of smaller stature
should not use the front-passenger seat.
Rthe front-passenger seat is occupied by an
adult or a person of a stature correspond-
ing to that of an adult, the PASSENGER AIR
BAG OFF indicator lamp goes out after the
system self-test. This indicates that the
front-passenger front air bag is activated.
If children are traveling in the vehicle, be sure
to observe the notes on "Children in the vehi-
cle" (
Ypage 61).
When OCS is malfunctioning, the red 6
restraint system warning lamp in the instru-
ment cluster and the PASSENGER AIR BAG
OFF indicator lamp light up simultaneously.
The front-passenger front air bag is deactiva- ted in this case and does not deploy during an
accident. Have the system checked by quali-
fied technicians as soon as possible. Consult
an authorized Mercedes-Benz Center. The
front-passenger seat should only be repaired
at an authorized Mercedes-Benz Center.
If the front-passenger seat, the seat cover or
the seat cushion is damaged, have the nec-
essary repair work carried out at an author-
ized Mercedes-Benz Center.
For safety reasons, Mercedes-Benz recom-
mends that you only use seat accessories
that have been approved by Mercedes-Benz.
Occupant safety55
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Z

If the driver's air bag deploys, this does not
mean that the front-passenger front air bag
will also deploy. The Occupant Classification
System (OCS) categorizes the occupant in the
front-passenger seat. Depending on that
result, the front-passenger front air bag is
either enabled or deactivated.
System self-test
GDANGER
If the PASSENGER AIR BAG OFF indicator
lamp does not light up during the system self-
test, then the system is malfunctioning. The
front-passenger front air bag might be trig-
gered unintentionally or might not be trig-
gered at all in the event of an accident with
high deceleration. This poses an increased
risk of injury or even fatal injury.
In this case the front-passenger seat may not
be used. Do not install a child restraint system
on the front-passenger seat. Have the Occu-
pant Classification System (OCS) checked
and repaired immediately at a qualified spe-
cialist workshop.
GDANGER
If the PASSENGER AIR BAG OFF indicator
lamp remains lit after the system self-test, the
front-passenger front air bag is disabled. It will
not be deployed in the event of an accident. In
this case, the front-passenger front air bag
cannot perform its intended protective func-
tion, e.g. when a person is seated in the front-
passenger seat.
That person could, for example, come into
contact with the vehicle's interior, especially
if the person is sitting too close to the dash-
board. This poses an increased risk of injury or
even fatal injury.
When the front-passenger seat is occupied,
always ensure that:
Rthe classification of the person in the front-
passenger seat is correct and the front-
passenger front air bag is enabled or disa-
bled in accordance with the person in the
front-passenger seat
Rthe person is seated properly with a cor-
rectly fastened seatbelt
Rthe front-passenger seat has been moved
back as far back as possible
If the PASSENGER AIR BAG OFF indicator
lamp remains lit when it should not, the front-
passenger seat may not be used. Do not
install a child restraint system on the front-
passenger seat. Have the Occupant Classifi-
cation System (OCS) checked and repaired
immediately at a qualified specialist work-
shop.
GWARNING
Objects between the seat surface and the
child restraint system could affect OCS oper- ation. This could result in the front-passenger
air bag not functioning as intended during an
accident. This poses an increased risk of
injury or even fatal injury.
Do not place any objects between the seat
surface and the child restraint system. 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, as far as
possible, be resting on the backrest of the
front-passenger seat. Always comply with the
child restraint system manufacturer's instal-
lation instructions.
After the system self-test, the PASSENGER
AIR BAG OFF indicator lamp displays the sta-
tus of the front-passenger front air bag
(
Ypage 54).
For more information about the OCS, see
"Problems with the Occupant Classification
System" (
Ypage 57).
56Occupant safety
Safety

Problems with the Occupant Classification System (OCS)
Be sure to observe the notes on "System self-test" (Ypage 56).
ProblemPossible causes/consequences andMSolutions
The PASSENGER AIR
BAG OFF indicator
lamp lights up and
remains lit, even
though the front-
passenger seat is occu-
pied by an adult or a
person of a stature cor-
responding to that of an
adult.The classification of the person on the front-passenger seat is
incorrect.
XMake sure the conditions for a correct classification of the per-
son on the front-passenger seat are met (
Ypage 53).
XIf the PASSENGER AIR BAG OFF indicator lamp remains lit, the
front-passenger seat may not be used.
XHave OCS checked as soon as possible at an authorized
Mercedes-Benz Center.
The PASSENGER AIR
BAG OFF indicator
lamp does not light up
and/or does not stay
on.
The front-passenger
seat is:
Runoccupied
Roccupied by the
weight of a child up
to 12 months old in a
child restraint sys-
tem
OCS is malfunctioning.
XMake sure there is nothing between the seat cushion and the
child seat.
XMake sure that the entire base of the child restraint system rests on the seat cushion of the front-passenger seat. The backrest of
the forward-facing child restraint system must lie as flat as pos-
sible against the backrest of the front-passenger seat. If nec-
essary, adjust the position of the front-passenger seat.
XWhen installing the child restraint system, make sure that the
seat belt is tight. Do not pull the seat belt tight using the front-
passenger seat adjustment. This could result in the seat belt and
the child restraint system being pulled too tightly.
XCheck for correct installation of the child restraint system.
Make sure that the head restraint does not apply a load to the
child restraint system. If necessary, adjust the head restraint
accordingly.
XMake sure that no objects are applying additional weight onto
the seat.
XIf the PASSENGER AIR BAG OFF indicator lamp remains off, do
not install a child restraint system on the front-passenger seat.
It is recommended that you install the child restraint system on
a suitable rear seat.
XHave OCS checked as soon as possible at an authorized
Mercedes-Benz Center.
Occupant safety57
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Z

Deployment of Emergency Tensioning
Devicesan dair bags
Important safet ynotes
GWARNING
The air bag parts are hot after an air bag has
bee ndeployed .There is aris kof injury.
Do no ttouch th eair bag parts .Hav e a
deployed air bag replaced at aqualified spe -
cialis tworkshop as soo nas possible.
GWARNING
A deployed air bag no longer offers any pro -
tection and canno tprovid eth eintended pro -
tection in an accident. There is an increase d
ris kof injury.
Hav eth evehicle towed to aqualified special-
ist workshop in order to hav e adeployed air
bag replaced.
It is important fo ryour safet yand that of your
passenger to hav edeployed air bags replaced
and to hav eany malfunctionin gair bags
repaired. Thi swill hel pto mak esur eth eair
bags continue to perform their protective
function fo rth evehicle occupant sin th e
event of acrash .
GWARNING
Pyrotechnic Emergency Tensioning Devices
that hav ebee ndeployed are no longer opera-
tional and are unable to perform their inten-
ded protective function .Thi sposes an
increase dris kof injury or eve nfatal injury.
Therefore, hav epyrotechni cEmergency Ten -
sioning Devices whic hhav ebee ntriggere d
immediately replaced at aqualified specialis t
workshop .
An electric moto ris used by PRE-SAF E®to
trigger th etightenin gof th eseat belt in haz -
ardous situations. Thi sprocedur eis reversi-
ble.
If Emergency Tensioning Devices are trig-
gered or air bags are deployed ,you will hear a
bang, and asmall amount of powder may also be released. The
6restrain tsystem warn -
in g lamp lights up.
Only in rar ecases will th eban gaffec tyour
hearing. The powder that is release dgener-
ally doe sno tconstitute ahealth hazard ,but it
may caus eshort-term breathin gdifficulties in
people wit hasthm aor other respirator yprob-
lems. To avoid this, you may wish to get out of
th evehicle or ope nth ewindows as soo nas it
is saf eto do so.
Ai rbags and pyrotechni cEmergency Tension-
in gDevices (ETDs) contain perchlorat emate-
rial ,whic hma
y require special handlin gand
regard fo rth eenvironment. National guide-
lines mus tbe observed durin gdisposal. In
California, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Method of operation
Duringth efirst stage of acollision ,th e
restrain tsystem contro luni tevaluates impor -
tant physical dat arelatin gto vehicle deceler -
ation or acceleration ,suc has:
Rduration
Rdirection
Rintensit y
Based on th eevaluation of this data, th e
restrain tsystem contro luni ttriggers th e
Emergency Tensioning Devices durin g afron -
ta lor rea rcollision .
An Emergency Tensioning Devic ecan only be
triggered, if:
Rth eignition is switched on
Rth ecomponent sof th erestrain tsystem are
operational; see "Restrain tsystem warnin g
lamp " (
Ypage 45)
Rthebelt tongue is engage din th ebuckl eon
th erespective front-passenger seat
The Emergency Tensioning Devices in th e
rea rcompartmen tare triggere dindepend -
entl yof th eloc kstatus of th eseat belts.
If th erestrain tsystem contro luni tdetects a
more severe accident, further component sof
58Occupant safety
Safety