MERCEDES-BENZ SLR 2007 R199 Repair Manual
Page 61 of 425
60 Safety and Security
Occupant safety
In this section you will learn the most im-
portant facts about the restraint systems
of the vehicle.
The restraint systems are
Seat belts (page 71)
Child restraints (page 76)
Additional protection potential provided by
Supplemental Restraint System (SRS)
with
Air bags (page 62)
Air bag control unit
(with crash sensors)
Emergency Tensioning Device
(ETD) for seat belts (
page 74)
Seat belt force limiter (page 74)Air bag system components with
Passenger front air bag off indicator
lamp (
page 70)
Passenger seat with Occupant Classifi-
cation S
ystem (OCS) (page 67)
Although independent systems, their
protective functions work in conjunction
with each other.The SRS system conducts a self-test when
the ignition is switched on and in regular
intervals while the engine is running. This
facilitates detection of malfunctions. The
1indicator lamp in the instrument
cluster comes on when the ignition is
switched on and goes out no later than a
few seconds after the engine has been
started.
The SRS components are in operational
readiness if the 1indicator lamp is not
lit when the engine is running.
A malfunction in the system has been
detected if the 1indicator lamp:
fails to go out after approximately
4 seconds after the engine was started
does not come on at all
comes on after the engine was started
or while driving
For more information, see the “Practical
hints” section (
page 310).
iFor information on infants and children
traveling with you in the vehicle and restraint
systems for infants and children, see “Children
in the vehicle” (
page 75).
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61 Safety and Security
Occupant safety
Warning!G
Modifications to or work improperly con-
ducted on restraint systems (such as seat
belts and anchors, emergency tensioning
devices, seat belt force limiters or air bags)
or their wiring, as well as tampering with
interconnected electronic systems, can lead
to the restraint systems no longer function-
ing as intended.
Air bags or emergency tensioning devices,
for example, could deploy inadvertently or
fail to deploy in accidents although the
deceleration threshold for air bag deploy-
ment is exceeded. Therefore, never modify
the restraint systems. Do not tamper with
electronic components or their software.
Warning!G
In the event that the 1 indicator lamp
comes on during driving or does not come
on at all, the SRS self-check has detected a
malfunction. For your safety, we strongly
recommend that you contact an authorized
Mercedes-Benz Center immediately to have
the system checked; otherwise the SRS may
not deploy when needed in an accident,
which could result in serious personal or
fatal injury, or it might deploy unexpectedly
and unnecessarily which could also result in
injury.
In addition, improper repair work on the SRS
creates a risk of rendering the SRS inopera-
tive or causing unintended air bag deploy-
ment. Work on the SRS must therefore only
be performed by qualified technicians. Con-
tact an authorized Mercedes-Benz Center.
If it is necessary to modify an air bag system
to accommodate a person with disabilities,
contact your local authorized
Mercedes-Benz Center or call our Customer
Assistance Center at 1-800-FOR-MERCedes
(1-800-367-6372) for details.
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62 Safety and Security
Occupant safety
Air bags
Warning!G
Air bags are designed to reduce the poten-
tial of injury and fatality in certain frontal
impacts (front air bags, knee air bags) or
side impacts (head-thorax air bags).
However, no system available today can
totally eliminate injuries and fatalities.
The deployment of the air bags temporarily
releases a small amount of dust from the air
bags. This dust, however, is neither injurious
to your health, nor does it indicate a fire in
the vehicle. The dust might cause some tem-
porary breathing difficulty for people with
asthma or other breathing trouble. To avoid
this, you may wish to get out of the vehicle
as soon as it is safe to do so. If you have any
breathing difficulty but cannot get out of the
vehicle after the air bag inflates, then get
fresh air by opening a window or door.
Warning!G
To reduce the risk of injury when the front
air bags inflate, it is very important for the
driver and passenger to always be in a prop-
erly seated position and to wear their seat
belts.
For maximum protection in the event of a
collision always be in normal seated position
with your back against the backrest. Fasten
your seat belt and make sure that it is prop-
erly positioned on your body (
page 45).
Since the air bag inflates with considerable
speed and force, a proper seating and hands
on steering wheel position will help to keep
you at a safe distance from the air bag.
Occupants who are unbelted, out of position
or too close to the air bag can be seriously
injured or killed by an air bag as it inflates
with great force in the blink of an eye:
Sit properly belted in a nearly upright
position with your back against the seat
backrest.
Adjust the driver’s seat as far as possi-
ble rearward, still permitting proper op-
eration of vehicle controls. The distance
from the center of the driver’s breast-
bone to the center of the air bag cover
on the steering wheel must be at least
10 inches (25 cm) or more. You should
be able to accomplish this by a combina-
tion of adjustments to the seat and
steering wheel. If you have any prob-
lems, please see an authorized
Mercedes-Benz Center.
Do not lean your head or chest close to
the steering wheel or dashboard.
Keep hands on the outside of steering
wheel rim. Placing hands and arms
inside the rim can increase the risk and
potential severity of hand/arm injury
when driver’s front air bag inflates.
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63 Safety and Security
Occupant safety
Adjust the passenger seat as far as pos-
sible rearward from the dashboard when
the seat is occupied.
Occupants, especially children, should
never place their bodies or lean their
heads in the area of the door where the
head-thorax air bag inflates. This could
result in serious injuries or death should
the air bag be deployed. Always sit as
upright as possible, properly use the
seat belts and an appropriately sized in-
fant, or toddler restraint, or booster seat
recommended for the size and weight of
the child.
Failure to follow these instructions can
result in severe injuries to you or other
occupants.
If you sell your vehicle, it is important that
you make the buyer aware of this safety
information. Be sure to give the buyer this
Operator’s Manual.
Warning!G
There is a possibility of a head-thorax air bag
related injury if occupants, especially chil-
dren, are not properly seated or restrained
when next to a head-thorax air bag which
needs to deploy rapidly in a side impact in
order to do its job.
To help avoid the possibility of injury, please
follow these guidelines:
(1) Occupants, especially children, should
never place their bodies or lean their
heads in the area of the door where the
head-thorax air bag inflates. This could
result in serious injuries or death should
the head-thorax air bag be deployed.
(2) Always sit as upright as possible, prop-
erly use the seat belts, and for children
12 years old or under, use an appropri-
ately sized infant, or toddler restraint, or
booster seat recommended for the size
and weight of the child.
(3) Always wear seat belts properly.
If you believe that, even with the use of
these guidelines, it would be safer for your
passenger seat occupants to have the pas-
senger head-thorax air bag deactivated,
then deactivation can be accomplished
upon your written request to do so at an
authorized Mercedes-Benz Center at an
additional cost.
Please contact your local authorized
Mercedes-Benz Center or call our Customer
Assistance Center (in the USA) at
1-800-FOR-MERCedes (1-800-367-6372) or
Customer Service (in Canada) at
1-800-387-0100 for details.
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64 Safety and Security
Occupant safety
Safety guidelines for the seat belt,
emergency tensioning device and air
bagiAir bags are designed to activate only in cer-
tain frontal impacts (front air bags, knee air
bags) and side impacts (head-thorax air bags)
which exceed preset thresholds. Only during
these types of impacts will they provide their
supplemental protection.
The driver and passenger should always wear
their seat belts. Otherwise it is not possible for
the air bags to provide their supplemental
protection.
In cases of other types of impacts and impacts
below air bag deployment thresholds, air bags
will not deploy. The driver and passenger will
then be protected to the extent possible by a
properly fastened seat belt. A properly fastened
seat belt is also needed to provide the best pos-
sible protection in a rollover.
We caution you not to rely on the presence of the
air bags in order to avoid wearing your seat belt.
It is important to your safety and that of your pas-
senger that you replace deployed air bags and
repair any malfunctioning air bags to ensure that
the vehicle will continue to provide supplemental
crash protection for occupants.
Warning!G
Damaged seat belts or seat belts that
were highly stressed in an accident
must be replaced and their anchoring
points must also be checked. Only use
seat belts installed or supplied by an
authorized Mercedes-Benz Center.
Air bags and Emergency Tensioning
Devices (ETDs) are designed to function
on a one-time-only basis. An air bag or
ETD that was activated must be
replaced.
Do not pass seat belts over sharp edges.
They could tear.
Do not make any modification that could
change the effectiveness of the seat
belts.
Do not bleach or dye seat belts as this
may severely weaken them. In a crash,
they may not be able to provide
adequate protection.
No modifications of any kind may be
made to any components or wiring of
the SRS. This includes changing or
removing any component or part of the
SRS, the installation of additional trim
material, badges, etc. over the steering
wheel hub, passenger front air bag cov-
er, outboard sides of the front seat
backrests, door trim panels, or door trim
panels, and installation of additional
electrical/electronic equipment on or
near SRS components and wiring. Keep
area between air bags and occupants
free from objects (e.g. packages,
purses, umbrellas, etc.).
Air bag system components will be hot
after an air bag has inflated. Do not
touch.
Never place your feet on the instrument
panel, dashboard, or on the seat. Always
keep both feet on the floor in front of the
seat.
Page 66 of 425
65 Safety and Security
Occupant safety
When you sell your vehicle, we strongly
urge you to give notice to the subsequent
owner that it is equipped with an SRS by
alerting them to the applicable section in
the Operator’s Manual.Front air bags
1Driver air bag
2Passenger air bag
Driver and passenger air bags are
deployed:
in the event of certain frontal impacts
if impact exceeds a preset deployment
threshold
independently of the head-thorax air
bagsThe air bags will not deploy in impacts
which do not exceed the system’s
deployment thresholds. You will then be
protected by the fastened seat belts.
In addition, improper repair work on the
SRS creates a risk of rendering the SRS
inoperative or causing unintended air
bag deployment. Work on the SRS must
therefore only be performed by qualified
technicians. Contact an authorized
Mercedes-Benz Center.
For your protection and the protection
of others, when scrapping the air bag
unit or emergency tensioning device,
our safety instructions must be fol-
lowed. These instructions are available
from your authorized Mercedes-Benz
Center.
Given the considerable deployment
speed, required inflation volume, and
the textile structure of the air bags,
there is the possibility of abrasions or
other, potentially more serious injuries
resulting from air bag deployment.
iThe front air bags in this vehicle have been
designed to inflate in two stages. This allows
the air bag to have different rates of inflation that
are based on the rate of relevant vehicle deceler-
ation as assessed by the air bag control unit.
On the passenger side, the front air bag
deployment is additionally influenced by the
passenger’s weight category as identified by the
Occupant Classification System (OCS)
(
page 67).
The lighter the passenger side occupant, the
higher the vehicle deceleration rate required for
the second stage inflation of the air bag.
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66 Safety and Security
Occupant safety
The passenger air bag will only be de-
ployed if:
the system, based on the OCS weight
sensor readings, senses that the pas-
senger seat is occupied
the PASSENGER AIR BAG OFF indicator
lamp in the lower part of the center
console is not lit (
page 70)
the impact exceeds a preset
deployment thresholdKnee air bags
1Knee air bag, driver’s side
2Knee air bag, passenger side
The knee air bags are located on the lower
instrument panel. They are designed to op-
erate together with the front air bags in
certain frontal impacts exceeding a preset
threshold. The knee air bags operate best
in conjunction with a properly positioned
and fastened seat belts and when the foot-
well is kept clear of objects.Head-thorax air bags
1Head-thorax air bag
The head-thorax air bags are deployed:
in impacts exceeding a preset deploy-
ment threshold
on the impacted side of the vehicle
independently of the front air bags
The head-thorax air bags are not deployed
in impacts which do not exceed the
system’s deployment threshold.
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67 Safety and Security
Occupant safety
Occupant Classification System
The O
ccupant Classification System (OCS)
automatically turns the passenger front air
bag and passenger-side knee air bag on or
off based on the classified occupant
weight category determined by weight
sensor readings from the passenger seat.
Occupants must sit properly belted in a
position that is as upright as possible with
their back against the seat backrest and
feet on the floor to be correctly classified.
If the occupant’s weight is transferred to
another object in the vehicle (e.g. by
leaning on armrests), the OCS may not be
able to properly approximate the
occupant’s weight category. Both driver and the passenger should
always use the PASSENGER AIR BAG OFF
indicator lamp (
page 70) as an indica-
tion of whether or not the passenger is
properly positioned.
iThe system does not deactivate the
head-thorax air bag and the emergency tension-
ing device.
iIf the seat needs to be serviced in any way,
take the vehicle to an authorized Mercedes-Benz
Center.
Only seat accessories approved by
Mercedes-Benz may be used. Warning!G
If the PASSENGER AIR BAG OFF indicator
lamp illuminates when an adult or someone
larger than a small individual is in the pas-
senger seat, have the passenger re-position
himself or herself in the seat until the
PASSENGER AIR BAG OFF indicator lamp
goes out.
For information on air bag display
messages, see (
page 319).
In the event of a collision, the air bag control
unit will not allow passenger front air bag or
passenger knee air bag deployment when
the OCS classified the passenger seat occu-
pant as being up to or less than the weight
of a typical 12-month-old child in a standard
child restraint or if the passenger seat is
sensed as being empty.
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68 Safety and Security
Occupant safety
When the OCS senses that the 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 PASSENGER AIR BAG OFF indi-
cator lamp will illuminate when the engine is
started and remain illuminated, indicating
that the passenger front air bag and passen-
ger knee air bag are deactivated.
When the OCS senses that the passenger
seat is classified as being empty, the
PASSENGER AIR BAG OFF indicator lamp
will illuminate when the engine is started
and remain illuminated, indicating that the
passenger front air bag and the passenger
knee air bag are deactivated. When the OCS senses that the 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 PASSENGER
AIR BAG OFF indicator lamp will illuminate
for approximately 6 seconds when the
engine is started and then, depending on
occupant weight sensor readings from the
seat, remain illuminated or go out. With the
PASSENGER AIR BAG OFF indicator lamp
illuminated, the passenger front air bag and
the passenger knee air bag are deactivated.
With the PASSENGER AIR BAG OFF indicator
lamp out, the passenger front air bag and
the passenger knee air bag are activated.
When the OCS senses that the passenger
seat occupant is classified as an adult or
someone larger than a small individual, the
PASSENGER AIR BAG OFF indicator lamp
will illuminate for approximately 6 seconds
when the engine is started and then go out,
indicating that the passenger front air bagand the passenger knee air bag are
activated.
If the PASSENGER AIR BAG OFF indicator
lamp is illuminated, the passenger front air
bag and the passenger knee air bag are
deactivated and will not be deployed.
If the PASSENGER AIR BAG OFF indicator
lamp is not illuminated, the passenger front
air bag and the passenger knee air bag are
activated and will be deployed:
in the event of certain frontal impacts
if impact exceeds a preset deployment
threshold
independently of the head-thorax air
bags
If the passenger front air bag and the pas-
senger knee air bag are deployed, the rate of
inflation will be influenced by:
the rate of relevant vehicle deceleration
as assessed by the air bag control unit
passenger’s weight category as identi-
fied by the Occupant Classification
System (OCS)
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69 Safety and Security
Occupant safety
Warning!G
Children 12 years old and under must be
seated and properly secured in an appropri-
ate infant or child restraint recommended
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 manufactur-
er’s instructions.
Children can be killed or seriously injured by
an inflating air bag. Note the following
important information:
Your vehicle is equipped with air bag
technology designed to turn off the pas-
senger front air bag and the passenger
knee air 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 passenger seat.
A child in a rear-facing child restraint on
the passenger seat will be seriously
injured or even killed if the passenger
front air bag and/or the passenger knee
air bag inflate in a collision which could
occur under some circumstances, even
with the air bag technology installed in
your vehicle.
If you install a rear-facing child restraint
on the passenger seat, make sure that
the PASSENGER AIR BAG OFF indicator
lamp is illuminated, indicating that the
passenger front air bag and the passen-
ger knee air bag are deactivated. Should
the PASSENGER AIR BAG OFF indicator
lamp not illuminate or go out while the
restraint is installed, please check in-
stallation. Periodically check the
PASSENGER AIR BAG OFF indicator
lamp while driving to make sure the
PASSENGER AIR BAG OFF indicator
lamp is illuminated. If the PASSENGER
AIR BAG OFF indicator lamp goes out or
remains out, do not transport a child on
the passenger seat until the system has
been repaired. A child in a rear-facing
child restraint on the passenger seat will
be seriously injured or even killed if the
passenger front air bag and/or the
passenger knee air bag inflate.
If you place a child in a forward-facing
child restraint on the passenger seat,
move the seat as far back as possible,
use the proper child restraint recom-
mended for the age, size and weight of
the child, and secure child restraint with
the vehicle’s seat belt according to the
child seat manufacturer’s instructions.
For children larger than the typical
12-month-old child, the passenger front
air bag and the passenger knee air bag
may or may not be activated
(
page 68).