MERCEDES-BENZ ML320 2002 W163 Workshop Manual

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Seat belts and integrated restraint system
Your vehicle is equipped with seat belts for all seats,
emergency tensioning retractors for front and second
row outboard seat belts, dual front airbags and door
mounted side impact airbags. Their protective functions
are designed to complement one another.
Seat belts
Important!
Laws in most states and all Canadian provinces require
seat belt use.
All states and provinces require use of child restraints
that comply with U.S. Federal Motor Vehicle Safety
Standard 213 and Canadian Motor Vehicle Safety
Standard 213.
All child restraint systems are designed to be secured in
vehicle seats by lap belts or the lap belt portion of a lap-
shoulder belt.
For your safety and that of your passengers we strongly
recommend their use.
Wa r n i n g !
Children 12 years old and under must never ride in
the front seat, except in a Mercedes-Benz
authorized BabySmart
TM compatible child seat,
which operates with the BabySmart
TM system
installed in the vehicle to deactivate the passenger
side front airbag when it is properly installed.
Otherwise they will be struck by the airbag when it
inflates in a crash. If this happens, serious or fatal
injury will result.
According to accident statistics, children are safer
when properly restrained in the rear seating
positions than in the front seating positions.
Infants and small children must ride in back seats
and be seated in an appropriate infant or child
restraint system, which is properly secured with
the vehicle’s seat belt, fully in accordance with the
child seat manufacturer’s instructions.A child’s risk of serious or fatal injuries is
significantly increased if the child restraints are
not properly secured in the vehicle and the child is
not properly secured in the child restraint.

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For cleaning and care of the seat belts, see page 302.
Seat belt nonusage warning system
After starting the engine, a warning sounds and the seat
belt warning lamp< remains illuminated for
approximately 6 seconds if the driver’s seat belt is not
fastened.
Wa r n i n g !
Never ride in a moving vehicle with the backrest
reclined. Sitting in an excessively reclined position
can be dangerous. You could slide under the seat
belt in a collision. If you slide under it, the belt
would apply force at the abdomen or neck. That
could cause serious or even fatal injuries. The
backrest and seat belt provide the best restraint
when the wearer is in an upright position and the
belt is properly positioned on the body.
Wa r n i n g !
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 for injury or
death is lessened if you are wearing your seat belt.Wa r n i n g !
Never let more people ride in the vehicle than there
are seat belts available. Be sure everyone riding in
the vehicle is correctly restrained with a separate
seat belt.

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Fastening of seat belts
1Latch plate
2Buckle
3Release buttonPush latch plate (1) into buckle (2) until it clicks. Do not
twist the belt. A twisted seat belt may cause injury.
To help avoid severe or fatal injuries, the lap belt must
be positioned as low as possible on your hips and not
across the abdomen.
Wa r n i n g !
Always fasten your seat belt before driving off.
Always make sure your passengers are properly
restrained – even those sitting in the rear.

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cluster displayPractical hints Car care Index Tighten the lap portion to a snug fit by pulling shoulder
portion up.
The shoulder portion of the seat belt must be pulled
snug and checked for snugness immediately after
engaging it.
Adjust seat belt so that shoulder portion is located as
close as possible to the middle of your shoulder (it
should not touch the neck). For this purpose, you can
adjust the height of the belt outlet. Three positions are
available.4Button for belt outlet height adjustment
To raise, slide belt height adjustment upward.
To lower, press button (4) and slide belt outlet
downward.
Caution!
For safety reasons, avoid adjusting the seat or backrest
into positions which could affect the correct seat belt
positioning.

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Operation
The inertia reel stops the belt from unwinding during
sudden vehicle stops or when quickly pulling on the
belt. The locking function of the reel may be checked by
quickly pulling out the belt.
Unfastening of seat belts
Push the release button (3) in the belt buckle (2).
Allow the retractor to completely rewind the seat belt by
guiding the latch plate (1).
Wa r n i n 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 section, as that could result
in serious injuries 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, including rollovers. The
integrated restraint system includes “SRS”
(driver airbag, front passenger airbag, front
and rear door mounted side impact airbags),
“ETR” (seat belt emergency tensioning
retractors for the outboard passenger seats
[except in the optional 3rd row seats]), and
front seat knee bolsters. The system is
designed to enhance the protection offered to
properly belted occupants in certain frontal
(front airbags) and side (side impact airbags)
impacts which exceed preset deployment
thresholds.

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• Never wear the shoulder belt under your arm,
against your neck or off your shoulder. In a
crash, your body would move too far forward.
That would increase the chance of head and
neck injuries. The belt would also apply too
much force to the ribs or abdomen, which
could severely injure internal organs such as
your liver or spleen.• Never wear belts over rigid or breakable
objects in or on your clothing, such as
eyeglasses, pens, keys etc., as these might
cause injuries.• Position the lap belt as low as possible on your
hips and not across the abdomen. If the belt is
positioned across your abdomen, it could cause
serious injuries in a crash.
• Each seat belt should never be used for more
than one person at a time. Do not fasten a seat
belt around a person and another person or
other objects.• Belts should not be worn twisted. In a crash,
you wouldn’t have the full width of the belt to
manage impact forces. The twisted belt against
your body could cause injuries.• Pregnant women should also use a lap-
shoulder belt. The lap belt portion should be
positioned as low as possible on the hips to
avoid any possible pressure on the abdomen.• Never place your feet on the instrument panel
or on the seat. Always keep both feet on the
floor in front of the seat.

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Wa r n i n g !
USE CHILD RESTRAINTS PROPERLY.
Children 12 years old and under must never ride in
the front seat, except in a Mercedes-Benz
authorized BabySmart
TM compatible child seat,
which operates with the BabySmart
TM system
installed in the vehicle to deactivate the passenger
front airbag when it is properly installed.
Otherwise they will be struck by the airbag when it
inflates in a crash. If this happens, serious or fatal
injury will result.
According to accident statistics, children are safer
when properly restrained in the rear seating
positions than in the front seating positions.
Infants and small children must ride in back seats
and be seated in an appropriate infant or child
restraint system, which is properly secured with
the vehicle’s seat belt, fully in accordance with the
child seat manufacturer’s instructions.
Wa r n i n g !
USE CHILD RESTRAINTS PROPERLY.A child’s risk of serious or fatal injuries is
significantly increased if the child restraints are
not properly secured in the vehicle and the child is
not properly secured in the child restraint.Children too big for child restraint systems must
ride in back seats using regular seat belts. Position
shoulder belt across chest and shoulder, not face or
neck. A booster seat may be necessary to achieve
proper belt positioning.

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TM airbag deactivation system
Special BabySmart
TM compatible child seats, designed
for use with the Mercedes-Benz system and available at
any authorized Mercedes-Benz Center are required for
use with the BabySmart
TM airbag deactivation system.
With the special child seat properly installed, the
passenger front airbag will not deploy. The 7
indicator lamp located in the instrument cluster will be
illuminated, except with key removed or in steering lock
position 0. The system does not deactivate the door
mounted side impact airbag.
Self-test BabySmart
TM
withoutspecialchildseatinstalled
After turning key in steering lock to position 1 or 2, the
7 indicator lamp located in the instrument cluster
comes on for approximately 6 seconds, extinguishes,
then blinks once.
If the indicator lamp should not come on or is
continuously lit, the system is not functioning. You must
see an authorized Mercedes-Benz Center before seating
any child on the front passenger seat.
BabySmart
TM is a trademark of Siemens Automotive Corp.
Wa r n i n g !
The BabySmart
TM Airbag Deactivation System will
ONLY work with a special child seat designed to
operate with it. It will not work with child seats
which are not BabySmart
TM compatible.
Never place anything between seat cushion and
child seat (e.g. pillow), since it reduces the
effectiveness of the deactivation 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 protecting
the child.
Follow the manufacturer’s instructions for
installation of special child seats.The passenger front airbag will not deploy only if
the 7 indicator lamp remains illuminated.Please be sure to check the indicator every time
you use the special system child seat.Should the light go out while the restraint is
installed, please check installation. If the light
remains out, do not use the BabySmart
TM restraint
to transport children on the front passenger seat
until the system has been repaired.

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Supplemental restraint system (SRS)
Airbags are intended as a supplement to seat belts.
Airbags alone cannot protect as well as airbags plus
seat belts in impacts for which the airbags were
designed to operate, and do not afford any protection
whatsoever in crashes for which the airbags are not
designed to deploy.
The SRS uses two crash severity levels (thresholds) to
activate either the Emergency Tensioning Retractor
(ETR) or front airbag or both. Activation depends on the
direction and severity of the impact exceeding the
preset thresholds and whether the seat belt is fastened.Seat belt fastened
•first threshold exceeded: ETR activates
•second threshold exceeded: airbag also activates
Seat belt not fastened
Front seats:
•first threshold exceeded:
airbag activates, but not ETR
Rear outer seats:
•first threshold exceeded:
ETR activates
Driver, front passenger and rear outer seat systems
operate independently of each other.

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The seat belts for the outboard passenger seats (except
in the optional 3rd row seats) are equipped with
emergency tensioning retractors. These tensioning
retractors are located in each belt’s inertia reel and
become operationally ready with the key in steering
lock position 1 or 2.
The emergency tensioning retractors are designed to
activate only when the seat belts are fastened during
frontal impacts exceeding the first threshold of the SRS
and in rear impacts exceeding a preset severity level.
They remove slack from the belts in such a way that the
seat belts fit more snugly against the body restricting its
forward movement as much as possible.In cases of other frontal impacts, angled impacts, roll-
overs, certain side impacts, or other accidents without
sufficient frontal or rear impact forces, the emergency
tensioning retractors will not be activated. The driver
and passengers will then be protected by the fastened
seat belts and inertia reel in the usual manner.
For seat belt and emergency tensioning retractor see
page 66.
Note:
The front passenger ETR activates only if the front
passenger seat is occupied.
Heavy objects on the front passenger seat can appear to
the “SRS” to indicate the presence of an occupant in
that seat which causes the passenger front airbag to
deploy and the ETR to activate in a crash exceeding the
appropriate threshold.