MERCEDES-BENZ S-Class 2011 W221 Service Manual

Rear seatsFunctionPage:Cup holder under the rear
seat armrest428
;Cup holder in the rear seat
armrest428
=Control panel for
multicontour seat in the
rear compartment106
?Stowage compartment in
the rear seat armrest424
AStowage box in the seat
backrest425
Rear seats39At a glance

40

Vehicle equipment ..............................42
Occupant safety .................................. 42
Children in the vehicle ........................60
Panic alarm .......................................... 66
Driving safety systems .......................66
Anti-theft systems .............................. 7341Safety

Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
which was available at the time of
purchase. Country-specific differences are
possible. Bear in mind that your vehicle
may not feature all functions described
here. This also refers to safety-related
systems and functions.
Occupant safety
Overview of occupant safety
In this section you will learn the most
important facts about the restraint system
components of the vehicle.
The restraint systems are:
R Seat belts
R Child restraint systems
R LATCH-type (ISOFIX) child seat anchors
Additional protection is provided by:
R SRS (Supplemental Restraint System)
R NECK-PRO head restraints
R PRE-SAFE ®
R Air bag system components with:
- PASSENGER air bag OFF indicator lamp
- USA only: front passenger seat with
Occupant Classification System (OCS)
- Canada only: front passenger seat with
BabySmart™ air bag deactivation system
The different air bag systems work
independently of each other. The protective
functions of the systems work in conjunction
with each other. Not all air bags are deployed
in an accident.
GWarning
Modifications to or work improperly
conducted on restraint system components
or their wiring, as well as tampering with
interconnected electronic systems, can lead
to the restraint systems no longer functioning
as intended.
Air bags or Emergency Tensioning Devices
(ETDs), for example, could deploy
inadvertently or fail to deploy in accidents
although the deceleration threshold for air
bag deployment is exceeded. Therefore,
never modify the restraint systems. Do not
tamper with electronic components or their
software.
i See "Children in the vehicle"
( Y page 60) for more information on
infants and children traveling with you in
the vehicle and restraints for infants and
children.
SRS (Supplemental Restraint System)
Introduction
SRS reduces the risk of occupants coming
into contact with the vehicle's interior in the
event of an accident. It can also reduce the
effect of the forces to which occupants are
subjected during an accident.
SRS consists of:
R the 6 SRS warning lamp
R air bags
R air bag control unit (with crash sensors)
R belt tensioners
R belt force limiters
SRS warning lamps
SRS functions are checked regularly when
you switch on the ignition and when the
engine is running. Therefore, malfunctions
can be detected in good time.
The 6 SRS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out no later than a few seconds
after the engine is started.
The SRS components are in operational
readiness when the 6 SRS warning lamp
goes out while the engine is running.
42Occupant safetySafety

GWarning
The SRS self-check has detected a
malfunction if the 6 SRS warning lamp:
R does not come on at all
R fails to go out approximately 4 seconds
after the engine was started
R comes on after the engine was started or
while driving
For your safety, Mercedes-Benz strongly
recommends that you have the system
checked as soon as possible at an authorized
Mercedes-Benz Center. Otherwise the SRS
may not be activated when it is needed in an
accident, which could result in serious or fatal
injury. The SRS might also deploy
unexpectedly and unnecessarily which could
also result in injury.
In addition, improper 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.
If it is necessary to modify an air bag system
to accommodate a person with disabilities,
contact an authorized Mercedes-Benz Center
for details. USA only: Call our Customer
Assistance Center at 1-800-FOR-MERCedes
(1-800-367-6372) for details.
Safety guidelines for the seat belt, the
Emergency Tensioning Device (ETD)
and the air bag
GWarning
R Damaged seat belts or seat belts that have
been subjected to stress in an accident
must be replaced. Their anchoring points
must also be checked. Only use seat belts
installed or supplied by an authorized
Mercedes-Benz Center.
R Air bags and pyrotechnic Emergency
Tensioning Devices (ETDs) contain
perchlorate material, which may require
special handling and regard for the
environment. Check your national disposal
guidelines. California residents, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm .
R Air bags and ETDs are designed to function
on a one-time-only basis. An air bag or ETD
that has deployed must be replaced. PRE-
SAFE ®
has electrically operated reversible
belt tensioners in addition to the
pyrotechnic ETDs.
R Do not pass seat belts over sharp edges.
They could tear.
R Do not make any modification that could
change the effectiveness of the seat belts.
R 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.
R No modifications of any kind may be made
to any components or wiring of the SRS.
R Do not change or remove any component
or part of the SRS.
R Do not install additional trim material, seat
covers, badges, etc. to the:
- padded steering wheel boss
- front-passenger air bag cover
- outer side of front seat bolsters
- side trim next to the rear seat backrest
- roof lining trim
R Do not install additional electrical/
electronic equipment on or near SRS
components and wiring.
R Keep area between air bags and occupants
free of objects (e.g. packages, purses,
umbrellas, etc.).
R Do not hang items such as coat hangers
from the coat hooks or handles over the
door. These items may be thrown around in
the vehicle and cause head and other
injuries when the window curtain air bag is
deployed.
R Air bag system components will be hot after
an air bag has inflated. Do not touch them.
R Never place your feet on the instrument
panel, dashboard, or on the seat. AlwaysOccupant safety43SafetyZ

keep both feet on the floor in front of the
seat.
R 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.
R For your protection and the protection of
others, when scrapping the air bag unit or
ETD, our safety instructions must be
followed. These instructions are available
from any authorized Mercedes-Benz
Center.
R Given the considerable deployment speed,
required inflation volume, and the material
of the air bags, there is the possibility of
abrasions or other, potentially more serious
injuries resulting from air bag deployment.
If you sell your vehicle, Mercedes-Benz
strongly recommends that you inform the
subsequent owner that the vehicle is
equipped with SRS. Also refer them to the
applicable section in the Operator's Manual.
Air bags
Important safety notes
GWarning
Air bags are designed to reduce the incidence
of injuries and fatalities in certain situations:
R frontal impacts (driver's and front-
passenger front air bags)
R side impacts (side impact air bags and
window curtain air bags)
R rollover (window curtain air bags)
However, no system available today can
completely eliminate injuries and fatalities.
When the air bags are deployed, a small
amount of powder is released. The powder
generally does not constitute a health hazard
and does not indicate that there is a fire in the
vehicle. In order to prevent potential
breathing difficulties, you should leave 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.GWarning
To reduce the risk of injuries during front air
bag inflation, the driver and front-passenger
must always be seated correctly and have
their seat belts fastened accordingly.
For maximum protection in the event of a
collision, you must always be in the normal
seat position with your back against the
backrest. Fasten your seat belt and make sure
that it is correctly positioned on your body.
Since the air bag inflates with considerable
speed and force, a proper seating position
and correct positioning of the hands on the
steering wheel will help to keep you at a safe
distance from the air bag. Occupants who are
not wearing their seat belt, are not seated
properly or are too close to the air bag can be
seriously injured or killed by an air bag as it
inflates with great force instantaneously:
R Sit with the seat belt properly fastened in a
position that is as upright as possible with
your back against the seat backrest.
R Move the driver's seat as far back as
possible, still permitting proper operation
of vehicle controls. The distance from the
center of the driver's chest 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
adjusting the seat and steering wheel. If
you have any difficulties, please contact an
authorized Mercedes-Benz Center.
R Do not lean your head or chest close to the
steering wheel or dashboard.
R Only hold the steering wheel by the rim.
Placing hands and arms inside the rim can
increase the risk and potential severity of
44Occupant safetySafety

hand/arm injury when the driver front air
bag inflates.
R Adjust the front-passenger seat as far back
as possible from the dashboard when the
seat is occupied.
R Occupants, especially children, should
never place their bodies or lean their heads
in the area of the door where the side
impact air bag inflates. This could result in
serious injuries or death should the side
impact air bag be deployed. Always sit as
upright as possible, wear the seat belt
properly and use an appropriately sized
child restraint, infant 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.GWarning!
Accident research shows that the safest place
for children in an automobile is in a rear seat.
There is a possibility for a side impact air bag-
related injury if occupants, especially
children, are not properly seated or restrained
when next to a side impact 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 side impact air bag
inflates. This could result in
serious injuries or death should
the side impact air bag be
deployed.(2)Always sit as upright as possible,
wear the seat belt properly and use
an appropriately sized infant
restraint, toddler restraint, orbooster seat recommended for the
size and weight of the child. and
for children 12 years old and
under, use an appropriately sized
infant restraint, 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 rear seat
occupants to have the rear mounted side
impact air bags deactivated, then
deactivation can be carried out upon your
written request at an authorized Mercedes-
Benz Center at an additional cost.
Please contact an authorized Mercedes-Benz
Center or call the 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.
The air bags are only deployed if the airbag
control unit detects the need for deployment.
Only in the event of such a situation 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 the event of other types of impacts and
impacts below air bag deployment
thresholds, air bags will not deploy. The driver
and passengers 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 possible
protection in a rollover.
Air bags provide additional protection; they
are not, however, a substitute for seat belts.
All vehicle occupants must fasten their seat
belts regardless of whether your vehicle is
equipped with air bags or not.
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
Occupant safety45SafetyZ

bags will continue to provide supplemental
crash protection for occupants.
Front air bags
GWarning
Observe "Important safety notes"
(Y page 44).
The front air bags increase protection for the
driver's and front-passenger's head and
chest.
Driver's air bag : deploys in front of the
steering wheel; front-passenger air bag ;
deploys in front of and above the glove box.
They are deployed:
Rin the event of certain frontal impacts
Rif the system determines that air bag
deployment can offer additional protection
to that provided by the seat belt
Rif the seat belt is fastened
Rindependently of other air bags in the
vehicle
If the vehicle overturns, the front air bags are
generally not deployed unless the system
detects high vehicle deceleration in a
longitudinal direction.
Your vehicle has adaptive, two-stage front air
bags. In the event of a collision, the air bag
control unit evaluates the vehicle
deceleration. When the first deployment
threshold is reached, the front air bag is filled
with enough propellant gas to reduce the risk
of injuries. The front air bag is fully deployed
if a second deployment threshold is exceeded
within a few milliseconds.
The deployment of the front-passenger air
bag is also influenced by the weight category
of the front passenger, which is determined
by the Occupant Classification System (OCS)
(Y page 48).
The lighter the passenger side occupant, the
higher the vehicle deceleration rate required
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.
In impact situations with deceleration or
acceleration values lower than the vehicle
deceleration or acceleration values preset in
the system, the front air bags are not
deployed. You will then be protected by the
seat belt.
The front-passenger air bag will only deploy
if:
Rthe system, based on the OCS weight
sensor readings, has detected that the
front-passenger seat is occupied.
Rthe 42 indicator lamp in the
center console is not lit, (Y page 48)
Rthe impact exceeds a preset deployment
threshold.
Side impact air bags
GWarning
Observe "Important safety notes"
(Y page 44).
GWarning!
The pressure sensors for side impact air bag
control are located in the doors. Do not
modify any components of the doors or door
trim panels including, for example, the
addition of door speakers.
Improper repair work on the doors or the
modification or addition of components to the
doors create a risk of rendering the side
impact air bags inoperative or causing
unintended air bag deployment. Work on the
46Occupant safetySafety

doors must therefore only be performed by
qualified technicians. Contact an authorized
Mercedes-Benz Center.
GWarning!
Only use seat covers which have been tested
and approved by Mercedes-Benz for your
vehicle model. Using other seat covers may
interfere with or prevent the deployment of
the side impact air bags. Contact an
authorized Mercedes-Benz Center for
availability.
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:
Rhead
Rneck
Rarms
Front side impact air bags : and rear side
impact air bags ; are deployed next to the
outer seat cushions.
The side impact air bags are deployed:
Ron the side on which an impact occurs
Rat the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
Rindependently of seat belt use
Rindependently of the front air bags
Rindependently of the belt tensioners
If the vehicle overturns, the side impact air
bags are generally not deployed. They 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.
The side impact air bags will not deploy in side
impacts with deceleration rates which do not
exceed the system’s preset deployment
thresholds for vehicle deceleration or
acceleration. You will then be protected by
the seat belt.
If the OCS detects that the front-passenger
seat is not occupied and the front-passenger
seat belt is not fastened (the belt tongue is
not engaged in the seat belt buckle), the side
impact air bag on the front-passenger side
will not deploy. 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.
Window curtain air bags
GWarning
Observe "Important safety notes"
(Y page 44).
The window curtain air 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 window curtain air bags are integrated
into the side of the roof frame and deploy in
the area extending from the front door (A-
pillar) to the rear door (C-pillar).
Occupant safety47SafetyZ

Window curtain 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 regardless of whether the front-passenger
seat is occupied
R independently of seat belt use
R if the vehicle overturns and the system
determines that window curtain air bag
deployment can offer additional protection
to that provided by the seat belt
R independently of the front air bags
Window curtain air bags : will not deploy in
impacts with deceleration rates which do not
exceed the system’s preset deployment
thresholds for vehicle deceleration or
acceleration. You will then be protected by
the seat belt.
Occupant classification system (OCS)
Operating principles of the Occupant
Classification System
OCS categorizes the occupant on the front-
passenger seat by means of a weight sensor.
The front-passenger front air bag is
automatically deactivated for certain weight
categories. The respective status can be
recognized by the 42 indicator
lamp. With the 42 indicator
lamp illuminated, the front-passenger front
air bag is deactivated.
The system does not deactivate:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Devices
To be classified correctly, the front passenger
must sit:
R with the seat belt properly fastened
R in a position that is as upright as possible
with the back against the seat backrest
R with their feet on the floor
If the front-passenger's weight is transferred
to another object in the vehicle (e.g. by
leaning on armrests), OCS may not be able to
approximate the occupant's weight category.
If the front passenger seat, the seat cover, or
the seat cushion are damaged, have the
necessary repair work carried out at an
authorized Mercedes-Benz Center.
For reasons of safety, Mercedes-Benz
recommends that you only use seat
accessories that have been approved by
Mercedes-Benz.
Both the driver and the front passenger
should observe the 42 indicator
lamp to determine whether or not the front
passenger is positioned correctly.GWarning
If the 42 indicator lamp lights up
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 42
indicator lamp goes out.
In the event of a collision, the air bag control
unit will not allow front-passenger front air
bag deployment when the OCS has classified
the front-passenger seat 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 empty.
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 42 indicator lamp
will illuminate when the engine is started and
remain illuminated, indicating that the front-
passenger front air bag is deactivated.
When the OCS senses that the front-
passenger seat is classified as being empty,
the 42 indicator lamp will
illuminate when the engine is started and
remain illuminated, indicating that the front-
passenger front air bag is deactivated.
48Occupant safetySafety