2018 MERCEDES-BENZ C-CLASS CABRIOLET Owner's Manual

of an accident, they could be crushed
between the vehicle occupant and seat belt.
Robjects are never secured with a seat belt if
the seat belt is also being used by one of the
vehicle's occupants
Also ensure that there are never objects
between a person and the seat, e.g. cushions.
Seat belts are only intended to secure and
restrain vehicle occupants. Always observe the
"Loading guidelines" for securing objects, lug-
gage or loads (
Ypage 263).
Fastening seat belts
Observe the safety notes on the seat belt
(Ypage 45) and the notes on correct use of seat
belts (Ypage 46).
GWARNING
If the seat-belt extender is extended during
the journey, the seat belt is not fitted properly
on the body. The seat belt can then no longer
perform its intended protective function. This
poses an increased risk of injury or even fatal
injury.
Always make sure that the seat-belt extender is retracted during a journey.
If the seat-belt extender does not retract auto-
matically, you can return it manually. Press the
seat-belt extender back to the stop before start-
ing the vehicle to do so. Returning the seat-belt
extender requires force.
The seat-belt extender for the driver and front
passenger helps you fasten your seat belt. Seat-
belt extender =is extended when the respec-
tive door is closed.
You can also extend seat-belt extender =with
seat-belt extender button ?.
XTurn the SmartKey to position 1or2 in the
ignition lock.
XPress seat-belt extender button ?.
Seat-belt extender =extends.
Seat-belt extender =is retracted again if:
Rthe belt tongue is engaged in the seat belt
buckle
Rthe belt tongue is not engaged in the seat belt
buckle within 60 seconds
In this case, you can extend seat-belt
extender =again. Press seat-belt extender
button ?again.
Rthe respective door is opened
Ryou release the seat backrest and fold it
forward
Rthe front-passenger seat remains unoccupied
If you then press seat-belt extender but-
ton ?, seat-belt extender =will not extend.
Basic illustration
Occupant safety47
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XAdjust the seat (Ypage 94).
The seat backrest must be in an almost
upright position.
XPull the seat belt smoothly out of seat-belt
extender =and engage belt tongue ;into
belt buckle :.
The seat belt on the driver’s seat and the
front-passenger seat may be tightened auto-
matically, see "Belt adjustment"
(
Ypage 48).
XIf necessary, pull up on the shoulder section
of the seat belt to tighten the belt across your
body.
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 60).
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. Damaged seat belts
can no longer fulfill their protective function
and must be replaced. Visit a qualified spe-
cialist workshop.
XPress the release button in the belt buckle,
hold the belt tongue firmly and guide the belt
back.
Seat belt adjustment
The belt adjustment is a convenience function
integrated into PRE-SAFE®. With this function,
the driver's and front-passenger seat belts are
adjusted to the upper body of the vehicle occu-
pant.
The seat belt strap will slightly tighten if:
Rthe belt tongue is inserted into the buckle and
Rthe ignition is switched on
The seat belt adjustment will apply a certain
tightening force if any slack is detected between
the vehicle occupant and the seat belt. Do not
grab hold of the seat belt.
You can switch the seat belt adjustment on and
off using the multimedia system. Information on
switching the seat belt adjustment on and off
can be found in the Digital Operating Instruc-
tions.
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 occu-
pants must wear their seat belts. It may 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, the 7seat belt warn-
ing lamp lights up for six seconds each time the
engine is started. If the doors are closed and the
driver's or front-passenger seat belt has not
been fastened, the 7seat belt warning lamp
lights up again after the six seconds. As soon as
the driver's and front-passenger seat belts are
fastened or a door is opened again, the 7
seat 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. The warning tone switches off after six
seconds or once the driver's seat belt is fas-
tened.
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 be lts d
uring the journey, the seat belt warn-
ing is activated again.
Air bags
Introduction
The installation point of an air bag can be rec-
ognized by the AIRBAG marking.
An air bag complements the correctly fastened
seat belt. It is no substitute for the seat belt. The
air bag provides additional protection in appli-
cable accident situations.
Not all air bags are deployed in an accident. The
different air bag systems function independ-
ently from one another (
Ypage 56).
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.
48Occupant safety
Safety

Important safety notes
GWARNING
If you do no tsit in th ecorrec tseat position ,
th eair bag canno tprotect as intended and
could eve ncaus eadditional injury when
deployed. This poses an increased ris kof
injury or eve nfatal injury.
To avoi dhazardous situations, always mak e
sur ethat all of th evehicle's occupants:
Rhave fastene dtheir seat belt scorrectly,
includin gpregnant wome n
Rare sitting correctl yand maintai nth egreat-
est possible distanc eto th eair bags
Rfollow th efollowin ginstruction s
Always mak esur ethat there are no objects
between th eair bag and th evehicle's occu-
pants .
RAdjus tth eseat sproperly before beginning
your journey. Always mak esur ethat th eseat
is in an almost upright position .The center of
th ehead restrain tmust support th ehead at
about eye level.
RMov eth edriver' sand front-passenger seat s
as far bac kas possible .The driver' sseat posi-
tion must allow th evehicl eto be driven safely.
ROnly hold th esteering whee lon th eoutside .
This allows th eair bag to be fully deployed.
RAlways lean against th ebackrest while driv -
ing .Do no tlean forward or lean against th e
door or side window. You may otherwise be in
th edeploymen tarea of th eair bags .
RAlways keep your fee tin th efootwell in fron t
of th eseat .Do no tput your fee ton th edash -
board, for example. Your fee tmay otherwise
be in th edeploymen tarea of th eair bag.
RFo rthis reason ,always secure person sless
than 5ft (1.5 0m) tall in suitable restraint sys-
tems. 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 is permanently lit, the front-
passenger front air bag is deactivated
(
Ypage 44).
RAlways observe the instructions and safety
notes on the "Occupant Classification System
(OCS)" (
Ypage 51) and on "Children in the
vehicle" (Ypage 59 )in addition to the child
restraint system manufacturer's installation
and operating 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
Rthere are no hard objects, e.g. coat hangers,
hanging on the grab handles or coat hooks
Rno accessories, such as cup holders, are
attached to the vehicle within the deployment
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
Occupant safety49
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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
!Do not place heavy objects on the front-
passenger seat. This could cause the system
to identify the seat as being occupied. In the
event of an accident, the restraint systems on
the front-passenger side may be triggered
and have to be replaced.
Driver's air bag :deploys in front of the steer-
ing 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 occu-
pants in the front seats.
The PASSENGER AIR BAG OFF indicator lamp
informs you about the status of the front-
passenger front air bag (
Ypage 44).
The front-passenger front air bag will only
deploy if:
Rthe system, based on the OCS weight sensor
readings, detects that the front-passenger
seat is occupied (
Ypage 51). The
PASSENGER AIR BAG OFF indicator lamp is
not lit (
Ypage 52)
Rthe restraint system control unit predicts a
high accident severity
Knee bags
Driver's knee bag :deploys underneath the
steering column and front-passenger knee
bag ;underneath the glove box. The driver's
and front-passenger knee bags are triggered
together with the front air bags.
The driver's and front-passenger knee bags
offer additional thigh, knee and lower leg pro-
tection for the occupants in the front seats.
Side impact air bags
GWARNING
Unsuitable seat covers can obstruct or pre-
vent deployment of the air bags integrated
into the seats. Consequently, the air bags
cannot protect vehicle occupants as they are designed to do. In addition, the operation of
the occupant classification system (OCS)
could be adversely affected. 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.
50Occupant safety
Safety

Front side impact air bags:and rear side
impact air bags ;deploy next to the outer bol-
ster of the seat backrest.
When deployed, the side impact air bag offers
additional thorax protection. However, it does
not protect the:
RHead
RNeck
RArms
If the restraint system control unit detects 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 deploys under the following conditions:
Rthe OCS system detects that the front-
passenger seat is occupied or
Rthe seat belt buckle 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 accident situation
occurs. In this case, deployment is independent
of whether the front-passenger seat is occupied
or not.
Head air bags
Head bags :deploy in the area of the side win-
dows at the front.
When deployed, the head bag enhances the
level of protection for the head. However, it does
not protect the:
Rchest
Rarms
If the restraint system control unit detects a side impact, the head 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 head bag may be deployed in other
accident situations (
Ypage 56).
The head bag on the front-passenger side
deploys under the following conditions:
Rthe OCS system detects that the front-
passenger seat is occupied or
Rthe seat belt buckle tongue is engaged in the belt buckle of the front-passenger seat
If the belt tongue is engaged in the belt buckle,
the head bag on the front-passenger side
deploys if an appropriate accident situation
occurs. In this case, deployment is independent
of whether the front-passenger seat is occupied
or not.
Occupant Classification System
(OCS)
Introduction
The Occupant Classification System (OCS) cat-
egorizes the person in the front-passenger seat.
Depending on that result, the front-passenger
front air bag and front-passenger knee bag are
either enabled or deactivated.
The system does not deactivate:
Rthe side impact air bag
Rthe headbag
Rthe Emergency Tensioning Devices
Requirements
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. a
Occupant safety51
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cushion. 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
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 and operating
instructions.
Occupant Classification System opera-
tion (OCS)
:PASSENGER AIR BAG ON indicator lamp
;PASSENGER AIR BAG OFF indicator lamp
The indicator lamps inform you whether the
front-passenger front air bag is deactivated or
enabled.
XPress the Start/Stop button once or twice, or turn the SmartKey to position 1or2 in the
ignition lock.
The system carries out self-diagnostics.
The PASSENGER AIR BAG OFF and PASSENGER
AIR BAG ON indicator lamps must light up simul-
taneously for approximately six seconds.
The indicator lamps display the status of the
front-passenger front air bag.
RPASSENGER AIR BAG ON lights up for 60 sec-
onds, subsequently both indicator lamps are
off (PASSENGER AIR BAG ON and OFF): the
front-passenger front air bag is able to deploy
in the event of an accident.
RPASSENGER AIR BAG OFF lights up: the front-
passenger front air bag is deactivated. It will then not be deployed in the event of an acci-
dent.
If the PASSENGER AIR BAG ON indicator lamp is
off, only the PASSENGER AIR BAG OFF indicator lamp shows the status of the front-passenger
front air bag. The PASSENGER AIR BAG OFF
indicator lamp may be lit continuously or be off.
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 instrument clus-
ter (
Ypage 222). 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 a
nd during the 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
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 rearward-facing child
restraint system on the front-passenger seat
and the PASSENGER AIR BAG OFF indicator
lamp is off, the front-passenger front air bag
may deploy in the event of an accident. The
52Occupant safety
Safety

child could be struck by the air bag. This posesan 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
stays off, 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 Sys-
tem" (
Ypage 55).
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, in the event of an
accident, the child could:
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.
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 outlet to the shoulder belt
guide on the child restraint system. The shoul-
der belt strap must be routed forwards and
downwards from the vehicle belt outlet. If
necessary, adjust the vehicle belt outlet 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 standard
child restraint system, the PASSENGER AIR
BAG OFF indicator lamp lights up a
fter thesystem self-test and remains lit. This indi-
cates 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 indi-
cates 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 install the child
restraint system on a suitable rear seat.
Rthe front-passenger seat is occupied by a per-
son with a smaller build (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. Alternatively, a per-
son 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 adult stature, the
PASSENGER AIR BAG OFF indicator lamp
goes out after the system self-test. This indi-
cates that the front-passenger front air bag is
activated.
If children are trave ling i
n the vehicle, be sure to
observe the notes on "Children in the vehicle"
(
Ypage 59).
When the Occupant Classification System
(OCS) is malfunctioning, the red 6restraint
system warning lamp on the instrument cluster
and the PASSENGER AIR BAG OFF indicator
lamp light up simultaneously. The front-
passenger front air bag is deactivated in this
case and does not deploy during an accident.
Have the Occupant Classification System (OCS)
checked and repaired immediately at a qualified
specialist workshop. Mercedes-Benz recom-
mends that you use an authorized Mercedes-
Benz Center for this purpose.
If the front-passenger seat, the seat cover or the
seat cushion are damaged, have the necessary
repair work carried out at a qualified specialist
workshop. Mercedes-Benz recommends that
you use an authorized Mercedes-Benz Center
for this purpose.
Occupant safety53
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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 Sys-
tem (OCS) categorizes the occupant on the
front-passenger seat. Depending on that result,
the front-passenger front air bag is either ena-
bled or deactivated.
System self-test
GDANGER
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 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.
GWARNING
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
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 or PASSENGER AIR BAG ON indicator
lamp displays the status of the front-passenger
front air bag (
Ypage 52). If the front-passenger
front air bag is enabled, the PASSENGER AIR
BAG ON indicator lamp lights up for 60 seconds and then goes out.
If the PASSENGER AIR BAG ON indicator lamp is
off, only the PASSENGER AIR BAG OFF indicator
lamp shows the status of the front-passenger
54Occupant safety
Safety