MERCEDES-BENZ C350 4MATIC 2007 W203 Repair Manual

60 Safety and Security
Occupant safety
Warning!G
To reduce the risk of injury when the front
air bags inflate, it is very important for the
driver and front passenger to always be in a
properly seated position and to wear their
respective 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.
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 in (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 in-
side the rim can increase the risk and
potential severity of hand/arm injury
when driver front air bag inflates.

Adjust the front passenger seat as far as
possible rearward from the dashboard
when the seat is occupied.

Occupants, especially children, should
always sit nearly upright, properly use
the seat belts and use an appropriately
sized infant or toddler restraint or boost-
er seat recommended for the size and
weight of the child.
Failure to follow these instructions can re-
sult 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 in-
formation. Be sure to give the buyer this
Operator’s Manual.

61 Safety and Security
Occupant safety
Warning!G
Accident research shows that the safest
place for children in an automobile is in the
rear seat.
There is a possibility for a side impact
air bag related injury if occupants, especial-
ly children, are not properly seated or re-
strained when next to a front side impact
air bag and/or rear side impact air bag*
which needs to deploy rapidly in a side im-
pact 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
front side impact air bag and/or the rear
side impact air bag* inflates. This could
result in serious injuries or death should
the front side impact air bag and/or the
rear side impact air bag* be deployed.
(2) Always sit as upright as possible,
properly use the seat belts, and for
children 12 years old and under, use an
appropriately 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
rear seat occupants to have the rear mount-
ed side impact air bags* deactivated, then
deactivation can be accomplished upon
your written request to do so at an autho-
rized Mercedes-Benz Center at an additional
cost.
Please contact your local authorized
Mercedes-Benz Center or call our Customer
Assistance Center at 1-800-FOR-MERCedes
(1-800-367-6372) for details.iAir bags are designed to deploy only in cer-
tain frontal impacts (front air bags) and in side
impacts (front side impact air bags, rear side im-
pact air bags* and window curtain air bags)
which exceed preset thresholds. Only during
these events will they provide their supplemental
protection.
The driver and passengers should always wear
their seat belts. Otherwise it is not possible for
the air bags to provide their supplemental pro-
tection.
In case of other types of impacts and impacts be-
low 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 possible pro-
tection 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-
sengers that you replace deployed air bags and
repair any malfunctioning air bags to make sure
that the vehicle will continue to provide supple-
mental crash protection for occupants.

62 Safety and Security
Occupant safety
Safety guidelines for the seat belt,
emergency tensioning device and
air bag
Warning!G

Damaged seat belts or belts that were
highly stressed in an accident must be
replaced and their anchoring points
must also be checked. Only use belts in-
stalled or supplied by an authorized
Mercedes-Benz Center.

Air bags and emergency tensioning de-
vices (ETDs) are designed to function on
a one-time-only basis. An air bag or ETD
that is deployed must be replaced.

Do not pass belts over sharp edges.
They could tear.

Do not make any modification that could
change the effectiveness of the belts.

Do not bleach or dye seat belts as this
may severely weaken them. In a crash
they may not be able to provide ade-
quate 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, front passenger front air bag
cover, outboard sides of the front seat
backrests, door trim panels, or door
frame trims, and installation of addition-
al electrical/electronic equipment on or
near SRS components and wiring. Keep
area between air bags and occupants
free from objects (e.g. packages, purs-
es, umbrellas, etc.).

Do not hang items such as coat hangers
from the coat hooks or handles over the
door. These items may turn into projec-
tiles and cause head and other injuries
when the window curtain air bag is de-
ployed.

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.

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.

63 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 bagDriver and front passenger front air bags
are deployed:

in the event of certain frontal impacts

if impact exceeds a preset deployment
threshold

independently of the front side impact
air bags and/or the rear side impact
air bags*The air bags will not deploy in impacts
which do not exceed the system’s deploy-
ment thresholds. You will then be protect-
ed by the fastened seat belts.
The front passenger front air bag will only
be deployed if:
the system, based on OCS weight sen-
sor readings, senses that the front pas-
senger seat is occupied

the 56indicator lamp in the
center console is not lit (
page 68)

the impact exceeds a preset deploy-
ment threshold
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 decelera-
tion as assessed by the air bag control unit.
On the front passenger side, the front air bag de-
ployment is additionally influenced by the pas-
senger’s weight category as identified by the
Occupant Classification System (OCS)
(
page 64).
The lighter the front passenger side occupant,
the higher the vehicle deceleration rate required
for the second stage inflation of the air bag.

64 Safety and Security
Occupant safety
Front side impact air bags, rear side im-
pact air bags*, window curtain air bags
1Window curtain air bag
2Front side impact air bag
3Rear side impact air bag*The front side impact air bags, the rear
side impact air bags*, and the window cur-
tain air bags are deployed:

on the impacted side of the vehicle

in impacts exceeding a preset deploy-
ment threshold

independently of the front air bags
The front side impact air bags, the rear
side impact air bags*, and the window cur-
tain air bags are not deployed in impacts
which do not exceed the system’s deploy-
ment threshold.
Occupant Classification System
The O
ccupant Classification System (OCS)
automatically turns the front passenger
front air bag on or off based on the classi-
fied occupant weight category determined
by weight sensor readings from the front
passenger seat.
Occupants must sit properly belted in a po-
sition 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.
iThe system does not deactivate the front
passenger side impact air bag, the window cur-
tain air bag and the emergency tensioning
device.

65 Safety and Security
Occupant safety
Both driver and the front passenger should
always use the 56indicator lamp
as an indication of whether or not the front
passenger is properly positioned.
iIf your seat, including your trim cover and
cushion 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 56indicator lamp illuminates
when an adult or someone larger than a
small individual is in the front passenger
seat, have the front passenger re-position
himself or herself in the seat until the
56indicator lamp goes out.
More information about air bag display
messages (
page 332).
In the event of a collision, the air bag control
unit will not allow front passenger front air
bag deployment when the OCS classified
the front passenger seat occupant as being
up to or less than the weight of a typical
12-month-old child in a standard child
restraint or if the front passenger seat is
sensed as being empty.
When the OCS senses that the front passen-
ger 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 56indicator lamp will
illuminate when the engine is started and re-
main illuminated, indicating that the front
passenger front air bag is deactivated.
When the OCS senses that the front passen-
ger seat is classified as being empty, the
56indicator 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 passen-
ger 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 56indicator lamp will illuminate
for approximately 6 seconds when the en-
gine is started and then, depending on occu-
pant weight sensor readings from the seat,
remain illuminated or go out. With the
56indicator lamp illuminated, the
front passenger front air bag is deactivated.
With the 56indicator lamp out, the
front passenger front air bag is activated.
When the OCS senses that the front passen-
ger seat occupant is classified as an adult or
someone larger than a small individual, the
56indicator lamp will illuminate for
approximately 6 seconds when the engine is
started and then go out, indicating that the
front passenger front air bag is activated.


66 Safety and Security
Occupant safety
If the 56indicator lamp is
illuminated, the front passenger front air
bag is deactivated and will not be deployed.
If the 56indicator lamp is not
illuminated, the front passenger front air
bag is activated and will be deployed:

in the event of certain frontal impacts

if impact exceeds a preset deployment
threshold

independently of the front side impact
air bags and/or rear side impact air
bags*.
If the front passenger front air bag is
deployed, the rate of inflation will be
influenced by:

the rate of vehicle deceleration as as-
sessed by the air bag control unit

front passenger’s weight category as
identified by the Occupant Classification
System (OCS).
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
appropriate infant or child restraint recom-
mended for the size and weight of the child.
The infant or child restraint must be properly
secured with the vehicle’s seat belt, the seat
belt and top tether strap, or lower anchors
and top tether strap, fully in accordance
with the child seat manufacturer’s
instructions.
Children can be killed or seriously injured by
an inflating air bag. Note the following
important information when circumstances
require you to place a child in the front
passenger seat:

Your vehicle is equipped with air bag
technology designed to turn off the front
passenger front 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 appropri-
ate child restraint on the front passen-
ger seat.

A child in a rear-facing child restraint on
the front passenger seat will be serious-
ly injured or even killed if the front pas-
senger front air bag inflates in a collision
which could occur under some circum-
stances, even with the air bag technolo-
gy installed in your vehicle. The only
means to completely eliminate this risk
is to never place a child in a rear-facing
child restraint in the front seat. We
therefore strongly recommend that you
always place a child in a rear-facing
child restraint in the back seat.


67 Safety and Security
Occupant safety

If you must install a rear-facing child
restraint on the front passenger seat
because circumstances require you to
do so, make sure that the 56 in-
dicator lamp is illuminated, indicating
that the front passenger front air bag is
deactivated. Should the 56 indi-
cator lamp not illuminate or go out while
the restraint is installed, please check
installation. Periodically check the
56 indicator lamp while driving
to make sure the 56indicator
lamp is illuminated. If the 56 in-
dicator lamp goes out or remains out, do
not transport a child on the front pas-
senger seat until the system has been
repaired. A child in a rear-facing child re-
straint on the front passenger seat will
be seriously injured or even killed if the
front passenger front air bag inflates.
If you have to place a child in a
forward-facing child restraint on the
front passenger seat, move the seat as
far back as possible, use the proper
child restraint recommended 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 front passenger
front air bag may or may not be
activated (
page 65).
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 64)
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.

68 Safety and Security
Occupant safety
The 56indicator lamp is located in
the center console.
1Front passenger front air bag off
indicator lamp
The 56indicator lamp1 will be
illuminated, except with the SmartKey
removed from the starter switch or with
the starter switch in position0.Self-test Occupant Classification
System
After turning the SmartKey in the starter
switch to position1 or2, the
56indicator lamp located in the
center console illuminates. If an adult oc-
cupant is properly sitting on the front pas-
senger seat and the system senses the
occupant as being an adult, the
56indicator 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 56indicator lamp will
illuminate and not go out.
Warning!G
If the 1indicator lamp and the
56indicator 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.

Sit properly belted in a nearly upright
position 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.

69 Safety and Security
Occupant safety
More information can be found in the
“Practical hints” section (
page 332).
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
fastened whenever the vehicle is in
motion.
For more information, see “Fastening the
seat belt” (
page 43).
Warning!G
If the 56indicator lamp should not
illuminate, the system is not functioning.
You must see an authorized Mercedes-Benz
Center before seating any child on the front
passenger seat.
Warning!G
Never place anything between seat cushion
and child seat (e.g. pillow), since it reduces
the effectiveness of the Occupant Classifi-
cation 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 protec-
tion for the child.
Follow the manufacturer’s instructions for
installation of child seats.
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 74).
Warning!G
Always fasten your seat belt before driving
off. Always make sure all of your passengers
are properly restrained, including those sit-
ting in the rear.
Failure to wear and properly fasten and
position 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 vehicle or be
ejected from it. You can be seriously 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
properly wearing their seat belts.