MERCEDES-BENZ S-Class 2015 W222 Repair Manual
Page 61 of 502
Window curtain air bags
Window curtain air bags
:are integrated
into the side of the roof frame and deployed in
the area from the A-pillar to the C-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
(Y page 65).
Cushion air bags i
Observe the "Important safety notes" sec-
tion (Y page 56).
The rear reclining seat is equipped with a
cushion air bag. If the seat backrest is
reclined, the cushion air bag can provide addi-
tional occupant protection in the event of
frontal collision situations. When triggered,
the cushion air bag deploys under the seat
cushion. This helps prevent the occupant
from slipping off the seat cushion. G
WARNING
If a child restraint system is installed and the
seat backrest is reclined too far backwards,
the cushion air bag may deploy by mistake in the event of an accident. There is an increased
risk of injury. When using a child restraint system, always
ensure that the seat is correctly adjusted and
that the backrest is almost vertical.
If you install a child restraint system on the
rear reclining seat, always observe: R the instructions and safety notes in "Chil-
dren in the vehicle" (Y page 69)
R the child restraint system manufacturer's
installation instructions. 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:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Devices
Prerequisites To be classified correctly, the front passenger
must sit:
R with the seat belt fastened correctly
R in an almost upright position with their
back against the seat backrest
R with 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:
R transfers their weight by supporting them-
selves on a vehicle armrest
R sits 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 Occupant safety
59Safety Z
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the child restraint system. Never place
objects under or behind the child restraint
system, e.g. cushions. Fully retract the seat
cushion length. The entire base of the child
restraint system must always rest on the seat cushion of the front-passenger seat. The
backrest of the forwards-facing child restraint
system must, as far as possible, be resting on the backrest of the front-passenger seat.
The child restraint system must not touch the
roof or be put under strain 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 Classification System opera-
tion (OCS) :
PASSENGER AIR BAG OFF indicator lamp
; PASSENGER AIR BAG ON indicator lamp
The indicator lamps inform you whether the
front-passenger front air bag is deactivated or
enabled.
X Press the Start/Stop button once or twice,
or turn the SmartKey to position 1or 2in
the ignition lock.
The system carries out self-diagnostics.
The PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps
must light up simultaneously for approx-
imately six second s. The indi
cator lamps display the status of the
front-passenger front air bag.
R PASSENGER AIR BAG OFF :lights up: the
front-passenger front air bag is deactiva-
ted. It will then not be deployed in the event
of an accident.
R PASSENGER AIR BAG ON ;lights 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.
If the status of the front-passenger front air
bag changes while the vehicle is in motion, an air bag display message appears in the instru-
ment cluster (Y page 332). When the front-
passenger seat is occupied, always pay atten-
tion to the PASSENGER AIR BAG ON and
PASSENGER AIR BAG OFF indicator lamps. Be aware of the status of the front-passenger
front air bag both before and during the jour- ney. G
WARNING
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:
R the 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
R the front-passenger seat has been moved
back as far back as possible.
R the 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. 60
Occupant safetySafety
Page 63 of 502
G
WARNING
If you secure a child in a rearward-facing child
restraint system on the front-passenger seat
and the PASSENGER AIR BAG ON indicator
lamp is lit up, the front-passenger front air bag may deploy in 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.
If the PASSENGER AIR BAG OFF indicator
lamp remains off and/or the PASSENGER AIR BAG ON indicator lamp lights up, do not install
a rearward-facing child restraint system on
the front-passenger seat. You can find more
information on OCS under "Problems with the Occupant Classification System"
(Y page 64). G
WARNING
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, in the event of an
accident, the child could:
R come into contact with the vehicle's inte-
rior if the PASSENGER AIR BAG OFF indi-
cator lamp is lit, for example
R be struck by the air bag if the PASSENGER
AIR BAG ON is lit up
This poses an increased risk of injury or even fatal injury.
Always move the front-passenger seat as far
back as possible and fully retract the seat
cushion length. 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 downwards from the vehicle belt sash
guide. If necessary, adjust the vehicle belt
sash guide and the front-passenger seat
accordingly. Always observe the child
restraint system manufacturer's installation
instructions. If OCS determines that:
R the 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.
R the front-passenger seat is occupied by a
child of up to 12 months old in a standard
child restraint system, the PASSENGER AIR BAG OFF indicator lamp lights up after the
system self-test and remains lit. This indi-
cates that the front-passenger front air bag
is deactivated.
But in the case of a 12-month-old child in a
standard child restraint system, the
PASSENGER AIR BAG ON can light up per-
manently after the system self-test. This
indicates that the front-passenger front air
bag is activated. The result of the classifi-
cation is dependent on, among other fac-
tors, the child restraint system and the
child's stature. It is recommended that you
install the child restraint system on a suit-
able rear seat.
R the front-passenger seat is occupied by a
person of smaller stature (e.g. a teenager
or small adult), either the PASSENGER AIR
BAG ON or PASSENGER AIR BAG OFF indi- cator lamp lights up and remains lit after
the system self-test depending on the
result of the classification.
- If the PASSENGER AIR BAG ON indicator
lamp lights up, 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.
R the 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 ON indicator lamp lights up after the
system self-test and remains lit. This indi-
cates that the front-passenger front air bag
is activated. Occupant safety
61Safety Z
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If children are traveling in the vehicle, be sure
to observe the notes on "Children in the vehi-
cle" (Y page 69).
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 orthe 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.
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 G
DANGER
If both the PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps do
not light up during the system self-test, the
system is malfunctioning. The front-
passenger front air bag might be triggered
unintentionally or might not be triggered at all in the event of an accident with high deceler-
ation. This poses an increased risk of injury or even fatal injury.
In this case the front-passenger seat may notbe 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. G
DANGER
If the PASSENGER AIR BAG OFF indicator
lamp remains lit after the system self-test, the front-passenger front air bag is disabled. It willnot 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:
R the 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
R the person is seated properly with a cor-
rectly fastened seatbelt
R the 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. G
WARNING
Objects between the seat surface and the
child restraint system could affect OCS oper- ation. This could result in the front-passengerair 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- 62
Occupant safetySafety
Page 65 of 502
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 or PASSENGER AIR BAG ON
indicator lamp display the status of the front- passenger front air bag (Y page 60).
For more information about the OCS, see
"Problems with the Occupant Classification
System" (Y page 64). Occupant safety
63Safety Z
Page 66 of 502
Problems with the Occupant Classification System (OCS)
Be sure to observe the notes on "System self-test" (Y
page 62).Problem
Possible causes/consequences and
M
MSolutions 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.
X Make sure the conditions for a correct classification of the per-
son on the front-passenger seat are met (Y page 59).
X If the PASSENGER AIR BAG OFF indicator lamp remains lit, the
front-passenger seat may not be used.
X Have 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:
R unoccupied
R occupied by the
weight of a child up
to 12 months old in a
child restraint sys-
tem OCS is malfunctioning.
X Make sure there is nothing between the seat cushion and the
child seat.
X Make 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.
X Make sure that the seat cushion length is fully retracted.
X When 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.
X Check 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.
X Make sure that no objects are applying additional weight onto
the seat.
X If the PASSENGER AIR BAG OFF indicator lamp remains off and/
or the PASSENGER AIR BAG ON indicator lamp lights up, 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.
X Have OCS checked as soon as possible at an authorized
Mercedes-Benz Center. 64
Occupant safetySafety
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Deployment of Emergency Tensioning
Devices and air bags
Important safety notes G
WARNING
The air bag parts are hot after an air bag has
been deployed. There is a risk of injury.
Do not touch the air bag parts. Have a
deployed air bag replaced at a qualified spe-
cialist workshop as soon as possible. G
WARNING
A deployed air bag no longer offers any pro-
tection and cannot provide the intended pro-
tection in an accident. There is an increased
risk of injury.
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. G
WARNING
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
trigger the tightening of the seat belt in haz-
ardous situations. This procedure is reversi-
ble.
If Emergency Tensioning Devices are trig-
gered or air bags are deployed, you will hear a bang, and a small amount of powder may also be released. The
6restraint system warn-
ing lamp lights up.
Only in rare cases will the bang affect your
hearing. The powder that is released gener-
ally does not constitute a health hazard, but it may cause short-term breathing difficulties in
people with asthma or other respiratory prob-
lems. To avoid this, you may wish to get out of
the vehicle or open the windows as soon as it is safe to do so.
Air bags and pyrotechnic Emergency Tension-
ing Devices (ETDs) contain perchlorate mate-
rial, which may require special handling and
regard for the environment. National guide-
lines 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 impor-
tant physical data relating to vehicle deceler-
ation or acceleration, such as:
R duration
R direction
R intensity
Based on the evaluation of this data, the
restraint system control unit triggers the
Emergency Tensioning Devices during a fron-
tal or rear collision.
An Emergency Tensioning Device can only be triggered, if:
R the ignition is switched on
R the components of the restraint system are
operational; see "Restraint system warning lamp" (Y page 50)
R the belt tongue is engaged in the buckle on
the respective front-passenger seat
The Emergency Tensioning Devices in the
rear compartment are triggered independ-
ently of the lock status of the seat belts. Occupant safety
65Safety Z
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Vehicles with belt bags:
the belt bags are
also deployed depending on the type and
severity of the accident.
Vehicles with a rear reclining seat: the
Emergency Tensioning Device is only trig-
gered if the belt buckle tongue is engaged in
the belt buckle.
If the seat backrest is reclined, the cushion air bag will also be deployed depending on the
type and severity of the accident.
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:
R Front air bags and driver's knee bag
R Window 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 indi-
cator lamp is lit. Observe the information on
the PASSENGER AIR BAG indicator lamps
(Y page 50).
Your vehicle has two-stage front air bags.
During the first deployment 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 pro-
pellant gas if a second deployment threshold
is reached within a few milliseconds.
The activation threshold of the Emergency
Tensioning Devices and the air bag are deter-
mined by evaluating the rate of vehicle decel-
eration or acceleration which occurs at vari-
ous points in the vehicle. This process is pre- emptive in nature. Deployment should take
place in good time at the start of the collision. The rate of vehicle deceleration or accelera-
tion and the direction of the force are essen-
tially determined by:
R the distribution of forces during the colli-
sion
R the collision angle
R the deformation characteristics of the vehi-
cle
R the characteristics of the object with which
the vehicle has collided
Factors which can only be seen and measured
after a collision has occurred do not play a
decisive role in the deployment of an air bag.
Nor do they provide an indication of air bag
deployment.
The vehicle can be deformed considerably,
without an air bag being deployed. This is the
case if only parts which are relatively easily
deformed are affected and the rate of decel-
eration is not high. Conversely, air bags may
be deployed even though the vehicle suffers
only minor deformation. This is the case if, for example, very rigid vehicle parts such as lon-
gitudinal body members are hit, and sufficient deceleration occurs as a result.
If the restraint system control unit detects a
side impact or that the vehicle is rolling over,
the relevant restraint system components are activated independently of one another
depending on the apparent type of accident.
If the system determines a need for additional
protection for the vehicle occupants, the
Emergency Tensioning Devices are triggered.
R Side impact air bags on the side of impact,
independently of the Emergency Tension-
ing Device and the use of the seat belt on
the driver's seat and outer seats in the sec-
ond row 66
Occupant safetySafety
Page 69 of 502
The side impact air bag on the front-
passenger side (front) deploys in the fol-
lowing situations:
- the OCS system detects that the front-
passenger seat is occupied or
- the belt tongue is engaged in the belt
buckle of the front-passenger seat
R Window curtain air bag on the side of
impact, independently of the use of the
seat belt and independently of whether the front-passenger seat is occupied
R Window curtain air bags on the driver's and
front-passenger side in certain situations
when the vehicle rolls over, if the system
determines that deployment can offer addi-
tional protection to that provided by the
seat belt
i Not all air bags are deployed in an acci-
dent. The different air bag systems work
independently of each other.
How the air bag system works is deter-
mined by the severity of the accident detec- ted, especially the vehicle deceleration or
acceleration and the apparent type of acci-dent:
R frontal collision
R side impact
R rollover PRE-SAFE
®
(anticipatory occupant
protection system)
Introduction In certain hazardous situations, PRE-SAFE
®
takes pre-emptive measures to protect the
vehicle occupants.
Important safety notes !
Make sure that there are no objects in the
footwell under or behind the seats when
moving the seats back. There is a risk that
the seats and/or the objects could be dam-
aged. Despite your vehicle being equipped with the
PRE-SAFE ®
system, the possibility of per-
sonal injuries occurring as a result of an acci- dent cannot be eliminated. Always adapt your
driving style to suit the prevailing road and
weather conditions and maintain a safe dis-
tance from the vehicle in front. Drive care-
fully.
Function PRE-SAFE
®
intervenes:
R in emergency braking situations, e.g. when
BAS is activated
R in critical driving situations, e.g. when phys-
ical limits are exceeded and the vehicle
understeers or oversteers severely
R vehicles with the Driving Assistance pack-
age: when a driver assistance system inter-
venes powerfully or the radar sensor sys-
tem detects an imminent danger of colli-
sion in certain situations
PRE-SAFE ®
takes the following measures
depending on the hazardous situation detec-
ted:
R the front seat belts are pre-tensioned.
R if the vehicle skids, the panorama roof with
power tilt/sliding panel and the side win-
dows are closed so that only a small gap
remains.
R the front-passenger seat is adjusted if it is
in an unfavorable position.
R for vehicles with electrically adjustable rear
seats: the outer rear seats are adjusted if
they are in an unfavorable position.
R vehicles with a multicontour seat: the air
pressure in the side bolsters of the seat
backrest is increased.
R vehicles with seat belt extenders: the seat
belts of the outer rear seats are pre-ten-
sioned.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pre-tensioning. On vehicles with mul-
ticontour seats, the air pressure in the side Occupant safety
67Safety Z
Page 70 of 502
bolsters is reduced again. All settings made
by PRE-SAFE ®
can then be reversed.
If the seat belt pre-tensioning is not reduced:
X Move 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. Infor-
mation about the convenience function can
be found under "Belt adjustment"
(Y page 55). 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 hazard-
ous situations, 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 when PRE-SAFE ®
PLUS intervenes.
PRE-SAFE ®
PLUS does not intervene if the
vehicle is backing up.
PRE-SAFE ®
PLUS does not perform braking
actions while the vehicle is in motion or when
Parking Guidance is active.
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 meas-
ures depending on the hazardous situation
detected:
R if the radar sensor system detects that a
head-on collision is imminent, the seat
belts are pre-tensioned.
R if 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 vehi-
cle is stationary.
- the seat belts are pre-tensioned.
The PRE-SAFE ®
PLUS braking application is
canceled:
R if the accelerator pedal is depressed when
a gear is engaged
R if the risk of a collision passes or is no lon-
ger detected
R if DISTRONIC PLUS indicates an intention
to pull away
If the hazardous situation passes without
resulting 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:
R the hazard warning lamps are activated
R the emergency lighting is activated
R the vehicle doors are unlocked
R the front side windows are lowered
R the electrically adjustable steering wheel is
raised
R the engine is switched off and the fuel sup-
ply is cut off
R vehicles with seat belt extenders: the seat-
belt buckles for the outer rear seats are
illuminated and extend forwards 68
Occupant safetySafety