MERCEDES-BENZ S550 4MATIC 2008 W221 Workshop Manual

50 Safety and Security
Occupant safety
The 59 indicator lamp is lo-
cated on the dashboard to the right of the
instrument cluster.
1Front passenger front air bag indicator
lamp
The 59indicator lamp1 will
be illuminated, except with the SmartKey
removed from the starter switch or with
the starter switch in position0
(
page 346).
iDeployment of the driver front air bag does
not mean that the front passenger front air bag
also should have deployed.
The Occupant Classification System (
page 47)
may have determined:

that the seat was empty or occupied by the
weight up to or less than that of a typical
12-month-old child seated in a standard
child restraint – both instances where the
system suppresses deployment of the front
passenger front air bag even though the im-
pact met the criteria and was of sufficient
severity to deploy the driver front air bag.

that the seat was occupied by a small individ-
ual (such as a young teenager or a small
adult) or a child weighing more than the
weight of a typical 12-month-old child in a
standard child restraint – instances where
the system may suppress deployment of the
front passenger front air bag even though
the impact met the criteria and was of suffi-
cient severity to deploy the driver front air
bag.
Warning!G
If the =indicator lamp and the
59 indicator lamp are lit at the
same time, there is a malfunction in the
Occupant Classification System. The front
passenger front air bag will be deactivated
in this case.
In order to ensure proper operation of the
air bag system and OCS:

Have the system checked as soon as
possible by qualified technicians.
Contact an authorized Mercedes-Benz
Center.

Do not place more than 4.4 lbs (2 kg)
into the ruffled storage bag on the back
of the front passenger seat. Otherwise,
the OCS may not be able to properly
approximate the occupant weight
category.

Do not place objects under and/or
around the front passenger seat.

Do not hang anything from or attach any
items to the seats.

51 Safety and Security
Occupant safety
Self-test Occupant Classification
System
After turning the SmartKey in the starter
switch to position1 or2 or pressing the
KEYLESS-GO* start/stop button once or
twice (
page 346), the 59
indicator lamp1 located in the center
console illuminates. If an adult occupant is
properly sitting on the front passenger
seat and the system senses the occupant
as being an adult, the 59 indi-
cator lamp will illuminate and go out after
approximately 6 seconds.
If the seat is not occupied and the system
senses the front passenger seat as being
empty, the 59indicator lamp
will illuminate and not go out.For more information, see the “Practical
hints” section (
page 610).
Do not stuff objects such as books be-
tween the middle console and the front
passenger seat.

Do not move the front passenger seat
backwards against stiff objects.

Sit properly belted in a position that is
as upright as possible with your back
against the seat backrest.

Do not lean on the armrests or lift your-
self from the seat by using the handle
over the door as this may cause the OCS
to be unable to correctly approximate
the occupant weight category.

Only have the seat repaired or replaced
by an authorized Mercedes-Benz Cen-
ter.

Read and observe all warnings in this
chapter.
Warning!G
If the 59 indicator lamp should
not illuminate, the system is not functioning.
You must contact an authorized
Mercedes-Benz Center before seating any
child on the front passenger seat.
Warning!G
Never place anything between seat cushion
(e.g. pillow), since it reduces the effective-
ness of the Occupant Classification System.
The bottom of the child seat must make full
contact with the passenger seat cushion. 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 seats.

52 Safety and Security
Occupant safety
Seat belts
The use of seat belts and infant and child
restraint systems is required by law in all
50 states, the District of Columbia, the
U.S. territories and all Canadian provinces.
Even where this is not the case, all vehicle
occupants should have their seat belts fas-
tened whenever the vehicle is in motion.For more information, see “Fastening the
seat belts” (
page 368).
iFor information on infants and children trav-
eling with you in the vehicle and restraint sys-
tems for infants and children, see “Children in
the vehicle” (
page 57).
Warning!G
Always fasten your seat belt before driving
off. Always make sure all of your passengers
are properly restrained.
Failure to wear and properly fasten and po-
sition your seat belt greatly increases your
risk of injuries and their likely severity in an
accident. You and your passengers should
always wear seat belts.
If you are ever in an accident, your injuries
can be considerably more severe without
your seat belt properly buckled.
Without your seat belt buckled, you are
much more likely to hit the interior of the ve-
hicle or be ejected from it. You can be seri-
ously injured or killed.
In the same crash, the possibility of injury or
death is lessened if you are properly wearing
your seat belt. Air bags can only protect as
they are designed if the occupants are prop-
erly wearing their seat belts.
Warning!G
Never ride in a moving vehicle with the seat
backrest in an excessively reclined position
as this can be dangerous. You could slide
under the seat belt in a collision. If you slide
under it, the seat belt would apply force at
the abdomen or neck. That could cause se-
rious or even fatal injuries. The seat back-
rest and seat belt provide the best restraint
when the wearer is in a nearly upright posi-
tion and the seat belt is properly positioned
on the body.

53 Safety and Security
Occupant safety
Warning!G
Never let more people ride in the vehicle
than there are seat belts available. Make
sure everyone riding in the vehicle is cor-
rectly restrained with a separate seat belt.
Never use a seat belt for more than one per-
son at a time.
Warning!G
Damaged seat belts or seat belts that were
highly stressed in an accident must be re-
placed and their anchoring points must also
be checked.
Only use seat belts which have been
approved by Mercedes-Benz.
Do not make any modifications to the seat
belts. This can lead to unintended activation
of the ETDs or to failure.
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.
Have all work carried out only by qualified
technicians. Contact an authorized
Mercedes-Benz Center.
Warning!G
USE SEAT BELTS PROPERLY

Seat belts can only work when used
properly. Never wear seat belts in any
other way than as described in this sec-
tion, as that could result in serious inju-
ries in case of an accident.

Each occupant should wear their seat
belt at all times, because seat belts help
reduce the likelihood of and potential
severity of injuries in accidents, includ-
ing rollovers. The integrated restraint
system includes SRS (driver air bag, pas-
senger front air bag, side impact air
bags, window curtain air bags for door
windows), ETD (seat belt emergency
tensioning device with seat belt force
limiters), and front seat knee bolsters.
The system is designed to enhance the
protection offered to properly belted oc-
cupants in certain frontal (front air bags
and ETD with seat belt force limiters)
and side (side impact and window cur-
tain air bags) impacts which exceed pre-
set deployment thresholds and in
certain rollovers (window curtain air
bags and ETD).

Never wear the shoulder belt under your
arm, against your neck or off your shoul-
der. In a frontal crash, your body would
move too far forward. That would in-
crease the chance of head and neck in-
juries. The seat belt would also apply too
much force to the ribs or abdomen,
which could severely injure internal or-
gans such as your liver or spleen.

Never wear seat belts over rigid or
breakable objects in or on your clothing,
such as eyeglasses, pens, SmartKeys,
etc., as these might cause injuries.


54 Safety and Security
Occupant safety
Enhanced seat belt reminder system
When the engine is started, the seat belt
telltale< will always illuminate for
6 seconds to remind you and your passen-
gers to fasten your seat belts.
If the driver’s seat belt is not fastened
when the engine is started, an additional
warning chime will also sound for a maxi-
mum of 6 seconds or until the driver’ s
seat belt is fastened.
If after these 6 seconds the driver’s or the
front passenger’s seat belt (with the front
passenger seat occupied) is not fastened
with front doors closed,

the seat belt telltale< remains illu-
minated for as long as either the driv-
er’s or front passenger’s seat belt is not
fastened.

and if the vehicle speed once exceeds
15 mph (25 km/h), the seat belt
telltale< starts flashing and a
warning chime sounds with increasing
intensity for a maximum of 60 seconds
or until the driver’s and the front pas-
senger’s seat belt are fastened.
If the driver’s or the front passenger’s
seat belt remains unfastened after
60 seconds, the warning chime stops
sounding, the seat belt telltale<
stops flashing but continues to be illu-
minated.
The seat belt telltale< will only go out
if both the driver’s and the front passen-
ger’s seat belt (with the front passenger
seat occupied) are fastened, or the vehicle
is standing still and a front door is opened.
For more information, see “Practical hints”
(
page 605).

Position the lap belt as low as possible
on your hips and not across the abdo-
men. If the seat belt is positioned across
your abdomen, it could cause serious in-
juries in a crash.

Never use a seat belt for more than one
person at time. Do not fasten a seat belt
around a person and another person or
other objects.

Seat belts should not be worn twisted.
In a crash, you wouldn’t have the full
width of the seat belt to distribute im-
pact forces. The twisted seat belt
against your body could cause injuries.

Pregnant women should also always use
a lap-shoulder belt. The lap belt portion
should be positioned as low as possible
on the hips to avoid any possible pres-
sure on the abdomen.

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.

When using a seat belt to secure infant
restraint, toddler restraint, or booster
seat, always follow the child seat manu-
facturer’s instructions.

55 Safety and Security
Occupant safety
Emergency tensioning device (ETD),
seat belt force limiter
The seat belts for the front and rear outer
seats are equipped with emergency ten-
sioning devices and seat belt force limit-
ers.
The ETD is designed to activate in the
following cases:

in frontal or rear-end impacts exceed-
ing the system deployment threshold

in certain vehicle rollovers

if the restraint systems are operational
and functioning correctly,
see=indicator lamp (
page 607)
In an impact, emergency tensioning
devices remove slack from the seat belts in
such a way that the seat belts fit more
snugly against the body. Seat belt force limiters, when activated, are employed to
help reduce the peak force exerted by the
seat belts on occupants during a crash.
Automatic comfort-fit feature seat belt
An automatic comfort-fit feature for the
front seats and for the rear outer seats*
(only for vehicles with rear power seat*)
reduces the retracting force of the seat
belts when they are in normal use.
Active head restraints
The active head restraints are intended to
offer the driver and front passenger in-
creased protection from whiplash type in-
juries. In the event of a rear-end collision,
the active head restraints on the driver’s
and front passenger’s seats are designed
to move forward in the direction of travel,
providing the head with increased support
earlier on in the collision sequence. The ac-
tive head restraints move forward whether
the seat is occupied or not.
iThe ETDs for the front seats will only acti-
vate if the front seat belt is fastened (latch plate
properly inserted into buckle).
The ETDs for the rear outer seats will activate
with or without the respective seat belt fastened.
Warning!G
A pyrotechnic emergency tensioning device
(ETD) that was activated must be replaced.
When disposing of the pyrotechnic emer-
gency tensioning device, our safety instruc-
tions must be followed. These are available
at any authorized Mercedes-Benz Center.
PRE-SAFE
® has electrically operated
reversible pre-tensioners that do not require
replacement after activation.
Warning!G
Do not attach any objects (e.g. hangers) to
the head restraint posts. Otherwise, the ac-
tive head restraints may not function prop-
erly or offer the degree of protection they
were designed for in the event of an acci-
dent.

56 Safety and Security
Occupant safety
If the active head restraints have been trig-
gered in an accident, the active head re-
straints must be reset. Otherwise, the
active head restraints cannot offer any ad-
ditional protection in the event of another
rear-end collision.
For information on resetting the activated
active head restraints, see “Resetting acti-
vated head restraints” (
page 675).
You cannot remove the active head re-
straint on the driver’s and front passen-
ger’s seats.
For removal contact an authorized
Mercedes-Benz Center.
For information on head restraint adjust-
ment, see “Head restraints” (
page 353).Preventive occupant safety
(PRE-SAFE®)
Your vehicle automatically takes preven-
tive measures to better protect the occu-
pants in the following hazardous
situations.
Warning!G
Only use seat or head restraint covers which
have been tested and approved by
Mercedes-Benz for your vehicle model.
Using other seat or head restraint covers
may interfere with or prevent the activation
of the active head restraints.
Contact an authorized Mercedes-Benz Cen-
ter for availability.
Warning!G
For your protection, drive only with properly
positioned head restraints.
Adjust 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.
Do not drive the vehicle without the seat
head restraints. Head restraints are intend-
ed to help reduce injuries during an acci-
dent.
Warning!G
The PRE-SAFE® system is intended to re-
duce the effects of an accident on properly
seat-belted vehicle occupants. Despite
having the PRE-SAFE
® system in your vehi-
cle, the possibility of injuries occurring as a
result of an accident cannot be eliminated.
Therefore, you should always drive carefully
and adjust your driving to the prevailing
road, weather, and traffic conditions.

57 Safety and Security
Occupant safety
PRE-SAFE® takes action in the following in-
stances:

Emergency braking situations, e.g.
when BAS (
page 68) is activated or
when
BAS Plus* (
page 69) is strongly inter-
vening.

Critical dynamic driving situations, e.g.
when the vehicle is understeering or
oversteering because it has exceeded
its physical limitations.

Evasive steering maneuvers at speeds
above 20 mph (30 km/h).
When you are driving faster than 20 mph
(30 km/h), PRE-SAFE
® takes the following
measures in such situations:

The front seat belts are pre-tensioned
electrically.

If the OCS senses that the front pas-
senger seat is occupied and the seat is
in an unfavorable position, it will be
adjusted to a better position.

If the vehicle is equipped with power
adjustable rear seats* and the passen-
ger outer seats are in an unfavorable
position, they will be adjusted to a bet-
ter position.

The system increases the air pressure
in the air pockets (on the sides of the
seat cushion and backrest) of the mul-
ticontour* and/or drive-dynamic front
seats*.

If the vehicle is understeering or over-
steering, the tilt/sliding sunroof and
the door windows also close until only
a small gap remains.
Once the hazardous situation is over with-
out an accident occurring, PRE-SAFE
®
loosens the seat belt pre-tension and de-
creases the air pressure in the air pockets
of the multicontour and drive-dynamic
seats*. You can readjust all of the settings
made by PRE-SAFE
®.If the seat belts do not release:
Adjust the backrest or seat slightly to
the rear until the seat belt tension is di-
minished.
The locking mechanism releases.
Children in the vehicle
If an infant or child is traveling with you in
the vehicle:
Secure the child using an infant or child
restraint appropriate to the age and
size of the child.
Make sure the infant or child is
properly secured at all times while the
vehicle is in motion.
iIf the closing procedure of the tilt/sliding
sunroof or power windows is blocked, the
tilt/sliding sunroof or power windows will stop
and open slightly.
!When moving the seat, make sure there are
no items in the footwell or behind the seats. Oth-
erwise you could damage the seats.

58 Safety and Security
Occupant safety
Infant and child restraint systems
We recommend all infants and children be
properly restrained at all times while the
vehicle is in motion.
All lap-shoulder belts except the driver’s
seat belt have special seat belt retractors
for secure fastening of child restraints.
To fasten a child restraint, follow child
restraint instructions for mounting. Then
pull the shoulder belt out completely and
let it retract. During seat belt retraction, a
ratcheting sound can be heard to indicate
that the special seat belt retractor is acti-
vated. The seat belt is now locked. Push
down on child restraint to take up any
slack.
Warning!G
Do not leave children unattended in the ve-
hicle, even if they are secured in a child re-
straint system. The children could

injure themselves on parts of the vehicle

be seriously or fatally injured through
excessive exposure to extreme heat or
cold
Do not expose the child restraint system to
direct sunlight. The child restraint system’s
metal parts, for example, could become very
hot, and the child could be burned on these
parts.
If children open a door, they could

injure other persons

get out of the car and injure themselves
or be injured by following traffic
Unsecured or improperly positioned cargo
increases a child’s risk of injury in the event
of

strong braking maneuvers

sudden changes of direction

an accident

59 Safety and Security
Occupant safety
To deactivate, release seat belt buckle and
let seat belt retract completely. To deacti-
vate the special seat belt retractor for the
front passenger seat, the front passenger
seat must be in the most backward posi-
tion. The seat belt can again be used in the
usual manner.
The use of infant or child restraints is re-
quired by law in all 50 states, the District
of Columbia, the U.S. territories and all Ca-
nadian provinces.Infants and small children should be seat-
ed in an appropriate infant or child re-
straint system properly secured in
accordance with the manufacturer’s in-
structions for the child restraint, that com-
plies with U.S. Federal Motor Vehicle
Safety Standards 213 and 225 and Canadi-
an Motor Vehicle Safety Standards 213
and 210.2.
A statement by the child restraint manu-
facturer of compliance with these stan-
dards can be found on the instruction label
on the restraint and in the instruction man-
ual provided with the restraint.
When using any infant or child restraint
system, make sure to carefully read and
follow all manufacturer’s instructions for
installation and use.
Please read and observe warning labels af-
fixed to the inside of the vehicle and to
infant or child restraints.
Warning!G
Never release the seat belt buckle while the
vehicle is in motion, since the special seat
belt retractor will be deactivated.
iInformation on child seats with mounting fit-
tings for tether anchorages (
page 61).
For information on LATCH-type child seat
mounts (
page 62).
Warning!G
According to accident statistics, children
are safer when properly restrained in the
rear seating positions than in the front seat-
ing position. Thus, we strongly recommend
that children be placed in the rear seats
whenever possible. Regardless of seating
position, children 12 years old and under
must be seated and properly secured in an
appropriately sized infant restraint, toddler
restraint, or booster seat recommended for
the size and weight of the child.