MERCEDES-BENZ SL-CLASS ROADSTER 2014 Workshop Manual

determined by the Occupant Classification
System (OCS) (Y
page 51).
The lighter the passenger-side occupant, the
higher the vehicle deceleration rate required
(predicted at the start of the impact) for
second-stage inflation of the front-passenger
front air bag. In the second stage, the front
air bags are inflated with the maximum
amount of propellant gas available.
The front air bags are not deployed in
situations where a low impact severity is
predicted. You will then be protected by the
fastened seat belt.
The front-passenger front air bag will only
deploy if:
R the system, based on the OCS weight
sensor readings, detects that the front-
passenger seat is occupied
R the PASSENGER AIR BAG OFF indicator
lamp on the center console is not lit
(Y page 51)
R the air bag control unit predicts a high
impact severity
Knee bags i
Observe the "Important safety notes"
section (Y page 46) Driver's knee bag
:deploys underneath the
steering column and front-passenger knee
bag ;underneath the glove box. They
deploy together with the front air bags. They
are designed to operate together with the
front air bags in frontal impacts if certain
thresholds are exceeded. The knee bags operate at best in conjunction with correctly
positioned and fastened seat belts.
Knee bags provide increased protection for
the driver and front passenger against the risk
of:
R
knee injuries
R thigh injuries
R lower leg injuries
Side impact air bags G
WARNING
Using unsuitable seat covers could restrict or
even prevent 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
function of the air bag deactivation system
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. G
WARNING
Sensors to control the air bags are located in
the doors. Modifications or work not
performed correctly to the doors or door
paneling, as well as damaged doors, can lead
to the function of the sensors being impaired.
The air bags might therefore not function
properly any more. 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
paneling carried out at a qualified specialist
workshop.
You should only use seat covers that have
been approved for your vehicle by Mercedes-
Benz. The seat covers must have a special
tear seam for side impact air bags. Otherwise,
the side impact air bags cannot deploy
correctly and therefore cannot provide the Occupant safety
49Safety Z

intended protection in the event of an
accident. Example: side impact air bag on the driver's side
Side impact air bags :deploy next to the
outer side bolsters of the seat backrest.
When deployed, the side impact air bags offer
additional protection for the thorax of the
vehicle occupants on the side of the vehicle
on which the impact occurs. However, they
do not protect the:
R head
R neck
R arms
The side impact air bags are deployed:
R on the side on which an impact occurs
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
R independently of the use of the seat belt
R independently of the front air bags
R independently of the ETDs
If the vehicle rolls over, the side impact air
bags are generally not deployed. Side impact
air bags are deployed if the system detects
high vehicle deceleration or acceleration in a
lateral direction and determines that side
impact air bag deployment can offer
additional protection to that provided by the
seat belt.
Side impact air bags will not deploy in side
impacts which do not exceed the system's
preset deployment thresholds for lateral
acceleration/deceleration. You will then be
protected by the fastened seat belt. The side impact air bag on the front-
passenger side does not deploy under the
following conditions:
R
the OCS system detects that the front-
passenger seat is not occupied, and
R the front-passenger seat belt is not
fastened.
The side impact air bag on the front-
passenger side will deploy if the front-
passenger seat belt is fastened, regardless of
whether the front-passenger seat is occupied
or not.
Head bags Example: head bag on the front-passenger side
Head bags
:deploy in the area of the side
windows at the front. Head bags enhance the
level of protection for the head, but not chest
or arms, of the vehicle occupants on the side
of the vehicle on which the impact occurs.
The head bags are deployed:
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
R on the side on which an impact occurs
R on the driver's side and passenger side, in
the event of a vehicle rollover and if the
system determines that air bag deployment
can offer the vehicle occupants additional
protection to that provided by the seat belt
R independently of the use of the seat belt
R independently of the front air bags
Head bags will not deploy in side impacts
which do not exceed the system's preset 50
Occupant safetySafety

deployment thresholds for lateral
acceleration/deceleration. You will then be
protected by the fastened seat belt.
The head bag on the front-passenger side is
not deployed in the following situations:
R the OCS system detects that the front-
passenger seat is not occupied, and
R the front-passenger seat belt is not
fastened.
The head bag on the front-passenger side will
deploy if the front-passenger seat belt is
fastened, regardless of whether the front-
passenger seat is occupied or not. Roll bar
G
DANGER
If the roll bar has developed a malfunction, it
may not function, e.g. in the event of an
accident. The roll bars may then not protect
the vehicle occupants as intended. This poses
an increased risk of injury or even fatal injury.
Have roll bars checked immediately at a
qualified specialist workshop. G
WARNING
If you place objects or clothing on the roll bar
covers, these could impair roll bar extension.
The roll bars may then not protect the vehicle
occupants as intended. In addition, objects
could endanger the vehicle occupants when
the roll bar is extending. This poses an
increased risk of injury or even fatal injury.
Ensure that the movement area of the roll bar
covers is kept clear. Always stow all objects
in the vehicle correctly. The roll bars are located in the rear area of
the vehicle under the two outer rear
compartment trim covers.
The roll bars are extended automatically if
systems detect that the vehicle is in danger
of rolling over. The two rear compartment
trim covers are opened and the roll bars are
extended within fractions of a second.
Once the roll bars are extended, you can no
longer lower them. An open roof can no
longer be closed. In this case, visit the nearest
qualified specialist workshop.
Occupant Classification System
(OCS)
Method of operation G
WARNING
If the 4 PASSENGER AIR BAG OFF
indicator lamp illuminates when an adult or
someone larger than a small individual is in
the front-passenger seat, have the front
passenger reposition himself or herself in the
seat until the 4PASSENGER AIR BAG OFF
indicator lamp goes out.
In the event of a collision, the air bag control
unit will not allow front-passenger front air
bag and front-passenger knee bag
deployment when the OCS has classified the
front-passenger occupant as weighing as
much as or less than a typical 12 month old
child in a standard child restraint or if the
front-passenger seat is classified as being
unoccupied. Occupant safety
51Safety
Z

When the OCS senses that the front-
passenger seat occupant is classified as
being up to or less than the weight of a typical
12-month-old child in a standard child
restraint, the 4PASSENGER AIR BAG OFF
indicator lamp will illuminate when the engine
is started and remain illuminated. This
indicates that the front-passenger front air
bag and the front-passenger knee bag are
deactivated.
When the OCS senses that the front-
passenger seat is classified as being empty,
the 4 PASSENGER AIR BAG OFF indicator
lamp will illuminate when the engine is started
and remain illuminated. This indicates that
the front-passenger front air bag and the
front-passenger knee bag are deactivated.
When the OCS senses that the front-
passenger seat occupant is classified as
being heavier than the weight of a typical 12-
month-old child seated in a standard child
restraint or as being a small individual (such
as a young teenager or a small adult), the
4 PASSENGER AIR BAG OFF indicator
lamp will illuminate for approximately 6
seconds when the engine is started.
Depending on occupant weight sensor
readings from the seat, it will then remain
illuminated or go out. If the 4PASSENGER
AIR BAG OFF indicator lamp is illuminated, the
front-passenger front air bag and the front-
passenger knee bag are deactivated. If the
4 PASSENGER AIR BAG OFF indicator
lamp is not illuminated, the front-passenger
front air bag and the front-passenger knee
bag are activated.
When the OCS senses that the front-
passenger seat occupant is classified as an
adult or someone larger than a small
individual, the 4PASSENGER AIR BAG
OFF indicator lamp will illuminate for
approximately six seconds when the engine is
started and then go out. This indicates that
the front-passenger front air bag and the
front-passenger knee bag are activated. If the
4 PASSENGER AIR BAG OFF
indicator lamp is illuminated, the front-
passenger front air bag and the front-
passenger knee bag are deactivated and are
not deployed.
If the 4 PASSENGER AIR BAG OFF
indicator lamp is not illuminated, the front-
passenger front air bag and the front-
passenger knee bag are activated and are
deployed:
R in certain front impacts
R independently of the side impact air bag
and head bag
R if the impact has exceeded a
predetermined threshold value for
deployment
If the front-passenger front air bag is
deployed, the rate of inflation will be
influenced by:
R the rate of vehicle deceleration as assessed
by the air bag control unit
R the front passenger's weight category as
determined by the OCS G
WARNING
Children under 12 years must be secured
correctly in a suitable infant or child restraint
system or booster seat suitable for the size
and weight of the child.
The infant or child restraint must be properly
secured with the vehicle's seat belt fully in
accordance with the child seat
manufacturer's instructions.
Occupants, in particular children, must sit as
upright as possible, fasten the seat belt
correctly and use a suitable infant restraint
system, child restraint system or booster seat
suitable for the size and weight of the child.
Children can be seriously or even fatally
injured by an air bag deploying.
Observe the following information:
R Your vehicle is equipped with air bag
technology designed to deactivate the
front-passenger front air bag and the front- 52
Occupant safetySafety

passenger knee bag in your vehicle when
the system senses the weight of a typical
12-month-old child or less along with the
weight of a standard appropriate child
restraint on the front-passenger seat.
R A child in a rear-facing child restraint
system on the front-passenger seat will be
seriously injured or even killed if the front-
passenger front air bag inflates in a collision
despite the air bag technology installed in
your vehicle, which could occur under some
circumstances.
R If you must install a rearward-facing child
restraint on the front-passenger seat, make
sure the 4PASSENGER AIR BAG OFF
indicator lamp is illuminated, indicating
that the front-passenger front air bag and
front-passenger knee bag are deactivated.
If the 4 PASSENGER AIR BAG OFF
indicator lamp does not light up or goes out
when a rearward-facing child restraint
system is installed, please check
installation. Periodically check the 4
PASSENGER AIR BAG OFF indicator lamp
while driving to make sure the 4
PASSENGER AIR BAG OFF indicator lamp is
illuminated. If the 4PASSENGER AIR
BAG OFF indicator lamp goes out or
remains out do not carry a child on the
front-passenger seat.
R A child in a rearward-facing child restraint
system on the front-passenger seat will be
seriously injured or even killed if the front-
passenger air bag is deployed. R
When securing a child in a child restraint
system on the front-passenger seat, you
must:
-move the front-passenger seat as far
back as possible
- use a child restraint system that is
suitable for the age, size and weight of
the child
- observe the manufacturer's installation
instructions in order to install and secure
the child restraint system correctly.
R For children larger than the typical 12-
month-old child, the front-passenger front
air bag may or may not be activated. G
WARNING
If the red 6SRS warning lamp in the
instrument cluster and the 4PASSENGER
AIR BAG OFF indicator lamp light up
simultaneously, the OCS is malfunctioning.
The front-passenger front air bag and the
front-passenger knee bag will be deactivated
in this case. Have the system checked as soon
as possible by qualified technicians. Consult
an authorized Mercedes-Benz Center.
Only have the seat repaired at an authorized
Mercedes-Benz Center.
In order to ensure correct operation of the air
bag system and OCS:
R sit with the seat belt fastened correctly and
in a position that is as upright as possible
with your back against the backrest.
R while seated, an occupant should not
position themselves in such a way as to
cause their weight to be lifted from the seat
cushion as this may result in OCS being
unable to correctly assess the occupant's
weight category.
R read and observe all warnings in this
section. Occupant safety
53Safety Z

:
PASSENGER AIR BAG OFF indicator lamp
; PASSENGER AIR BAG ON indicator lamp
If the SmartKey is removed from the ignition
lock or is in position 0, PASSENGER AIR BAG
OFF indicator lamp :does not light up.
PASSENGER AIR BAG ON indicator lamp ;
has no function. It lights up briefly when the
ignition is switched on and then goes out
again.
Occupant Classification System (OCS)
categories the occupant on the front-
passenger seat using a weight sensor. The
front-passenger front air bag and the front-
passenger knee bag are deactivated
automatically for certain weight categories.
PASSENGER AIR BAG OFF indicator lamp :
shows you the current status. If PASSENGER
AIR BAG OFF indicator lamp :lights up, the
front-passenger front air bag and the front-
passenger knee bag are deactivated.
The system does not deactivate:
R the side impact air bag
R the front-passenger head bag
R the Emergency Tensioning Devices
To be classified correctly, the front passenger
must sit:
R with the seat belt fastened correctly
R in a position that is as upright as possible
with their back against the seat backrest
R with their feet on the floor
The OCS weight sensor reading is affected if
the occupant's weight is transferred, e.g. by
leaning on the armrest. 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 only
use seat accessories which have been
approved by Mercedes-Benz.
Both the driver and the front passenger
should always observe PASSENGER AIR BAG
OFF indicator lamp
:as an indication of
whether or not the front passenger is
positioned correctly. Observe also the air bag
display messages that can be displayed in the
instrument cluster (Y page 170).
If the driver's air bag deploys, this does not
mean that the front-passenger front air bag
will also deploy.
The OCS may have detected that the seat:
R is empty or occupied by the weight of a
typical child up to twelve months old,
seated in a child restraint system.
R is occupied by a small individual, such as a
young teenager or a small adult.
R is occupied by a child in a child restraint
system whose weight is greater than that
of a typical twelve month old child.
These are examples of when the OCS
deactivates the front-passenger front air bag
and front-passenger knee bag. Deactivation
takes place although the collision fulfills the
criteria for deploying the driver's air bag.
For further information, see "Air bag display
messages" (Y page 170).
System self-test G
WARNING
If the 4 PASSENGER AIR BAG OFF
indicator lamp does not illuminate, the system
is not functioning. Consult an authorized
Mercedes-Benz Center before seating a child
on the front-passenger seat. 54
Occupant safetySafety

G
WARNING
Never place anything between seat cushion
and child seat (e.g. a pillow), since it reduces
the effectiveness of the OCS. The underside
and rear side child restraint system must be
placed entirely on the seat cushion and the
backrest of the front-passenger seat
backrest.
If necessary, adjust the tilt of the passenger
seat backrest.
An incorrectly mounted child seat could cause
injuries to the child in case of an accident,
instead of increasing protection for the child.
Follow the manufacturer's instructions for
installation of child restraint systems.
The PASSENGER AIR BAG OFF indicator lamp
lights up:
R if you turn the SmartKey in the ignition lock
to position 1or 2
R if you press the KEYLESS-GO Start/Stop
button once or twice on vehicles with
KEYLESS-GO
R if an adult is seated properly on the front-
passenger seat and the OCS classifies the
occupant as an adult
The PASSENGER AIR BAG OFF indicator lamp
goes out again after approximately
6 seconds.
If the seat is not occupied and the OCS
detects that the front-passenger seat is
empty, the PASSENGER AIR BAG OFF
indicator lamp will continue to light up. The
PASSENGER AIR BAG OFF indicator lamp will
not go out.
For more information about the OCS, see
"Problems with the Occupant Classification
System" (Y page 56). Occupant safety
55Safety Z

Problems with the occupant classification system
G
WARNING
If the 4 PASSENGER AIR BAG OFF indicator lamp illuminates and remains illuminated when
the weight of a typical adult or an individual that is the size of a typical adult has been detected
on the front-passenger seat, do not allow any occupant to use the front-passenger seat until the
system has been repaired. G
WARNING
If the 4 PASSENGER AIR BAG OFF indicator lamp does not illuminate or remains out with the
weight of a typical 12-month-old child in a standard child restraint or less, or is unoccupied, on
the front-passenger seat, do not transport a child on the front-passenger seat until the system
has been repaired. Problem Possible causes/consequences and
M MSolutions The PASSENGER AIR
BAG OFF indicator
lights up and remains
on.
The person on the
front-passenger seat:
R has the weight of a
typical adult
R has been determined
by the system not to
be a child The OCS is malfunctioning.
X
Have the OCS checked as soon as possible at a qualified
specialist workshop.
X Observe the additional display messages in the multifunction
display (Y page 170). Problem Possible causes/consequences and
M MSolutions The PASSENGER AIR
BAG OFF indicator
lamp does not light up
and/or stays on.
The front-passenger
seat is:
R unoccupied
R occupied with the
weight of a child up
to twelve months old
in a child restraint
system The OCS is malfunctioning.
X
Make sure there is nothing between the seat cushion and the
child seat.
X Check the installation of the child restraint system.
X Make sure that no objects are applying additional weight onto
the seat.
X If the PASSENGER AIR BAG OFF indicator lamp remains off, have
the OCS system checked as soon as possible at a qualified
specialist workshop. Do not transport a child on the front-
passenger seat until the OCS has been repaired.
X Observe the additional display messages in the multifunction
display (Y page 170). 56
Occupant safetySafety

PRE-SAFE
®
(anticipatory occupant
protection system)
Introduction PRE-SAFE
®
takes preemptive measures to
protect occupants in certain hazardous
situations.
Important safety notes !
Make sure that there are no objects in the
footwell or behind the seats when resetting
the seats. There is a risk that the seats
and/or the objects could be damaged.
Despite your vehicle being equipped with the
PRE-SAFE ®
system, the possibility of
personal injuries occurring as a result of an
accident cannot be eliminated.
Always adapt your driving style to suit the
prevailing road and weather conditions and
maintain a safe distance from the vehicle in
front. Drive carefully.
Function PRE-SAFE
®
intervenes:
R in emergency braking situations, e.g. when
BAS is activated.
R in critical driving situations, e.g. when
physical limits are exceeded and the
vehicle understeers or oversteers severely.
R on vehicles with DISTRONIC PLUS: if
BAS PLUS brakes hard or the radar sensor
system detects an imminent danger of
collision in certain situations.
PRE-SAFE ®
takes the following measures
depending on the hazardous situation
detected:
R the seat belts are pre-tensioned.
R if the vehicle skids, the side windows are
closed so that only a small gap remains. R
the front-passenger seat is adjusted if it is
in an unfavorable position.
R Vehicles with a multicontour seat or
active multicontour seat: the air
pressure in the side bolsters is increased.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pre-tensioning. All settings made by
PRE-SAFE ®
can then be reversed.
If the seat belts are not released:
X When the vehicle is stationary, move the
backrest or seat back slightly.
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. More
information about seat-belt adjustment can
be found under "Seat-belt adjustment"
(Y page 60). NECK-PRO head restraints
Important safety notes G
WARNING
Do not secure any objects (e.g. coat hangers)
on the NECK-PRO head restraints. Otherwise,
the NECK-PRO head restraints may not
function properly, or in the event of a rear-end
collision may not be able offer the level of
protection they are designed to provide. G
WARNING
Seat or head restraint covers can cause a
malfunction when the NECK-PRO head
restraints are activated or when the side
impact air bags are deployed, or they can
prevent this completely. The NECK-PRO head
restraints or side impact air bags can
therefore not provide the intended protection.
Do not use any seat or head restraint covers. G
WARNING
For your protection, drive only with properly
positioned head restraints. Occupant safety
57Safety
Z

Adjust the head restraint so that it is as close
to the head as possible and the center of the
head restraint supports the back of the head
at eye level. This will reduce the potential for
injury to the head and neck in the event of an
accident or similar situation. G
WARNING
For safety reasons, have the NECK-PRO head
restraints checked at a qualified specialist
workshop after a rear-end collision.
The NECK-PRO head restraints reduce the
likelihood of head and chest injuries. The
NECK-PRO head restraints on the driver's and
front-passenger seats are moved forwards
and upwards in the event of a rear-end
collision of a certain severity. This provides
better head support.
If the NECK-PRO head restraints have been
triggered in an accident, reset the NECK-PRO
head restraints on the driver’s and front-
passenger seat (Y page 58). Otherwise, the
additional protection will not be available in
the event of another rear-end collision. You
can recognize when NECK-PRO head
restraints have been triggered by the fact that
they have moved forwards and can no longer
be adjusted.
Resetting triggered NECK-PRO head
restraints G
WARNING
When pushing back the NECK-PRO head
restraint cushion, make sure your fingers do
not become caught between the head
restraint cushion and the cover. Failure to
observe this could result in injuries. X
Tilt the top of the NECK-PRO head restraint
cushion forwards in the direction of
arrow :.
X Push the NECK-PRO head restraint cushion
down in the direction of arrow ;as far as
it will go.
X Firmly push the NECK-PRO head restraint
cushion back in the direction of arrow =
until the cushion engages.
X Repeat this procedure for the second
NECK-PRO head restraint.
i Resetting the NECK-PRO head restraints
requires a lot of strength. If you have
difficulty resetting the NECK-PRO head
restraints, have this work carried out at a
qualified specialist workshop. Seat belts
Important safety notes G
WARNING
The seat belt does not offer the intended level
of protection if the backrest is not in the
upright position. When braking 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 make sure that the seat
is in the upright position. 58
Occupant safetySafety