Mercedes-Benz S 320 CDI, Owner'S Manual, Page: 58 / 588

36
Safety
Occupant safety
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Airbags are not deployed in all types of acci-
dent. They are controlled by complex sensor
technology and evaluation logic. This process is
pre-emptive in nature as airbag deployment
must take place during the impact and must be
adapted to provide calculated, additional protec-
tion for the vehicle occupants. Not all airbags are
deployed in an accident.
The different airbag systems work independently
of each other. However, the deployment of each
individual system depends on the type of acci-
dent determined by the control system in the
first stages of the collision (head-on collision,
side impact and overturn) and the extent of the
accident (in particular, vehicle’s rate of deceler-
ation or acceleration).
The vehicle deceleration or acceleration
and the direction of the force are basically
determined by:
앫
the distribution of forces during the col-
lision
앫
the collision angle
앫
the deformation characteristics of the
vehicle
앫
the characteristics of the object with
which the vehicle has collided, e.g. the
other vehicle
Factors which can only be seen and meas-
ured after the collision has taken place do
not play a decisive role in the deployment
of an airbag, nor do they provide an indica-
tion of it.
The vehicle may be considerably deformed
without an airbag being deployed, if, for ex-
ample, only easily deformable parts, such
as the bonnet or front wing, have been hit
and the necessary degree of deceleration
has not been reached. It is also possible
that airbags may be deployed even though
the vehicle is only slightly deformed, if, for
example, very rigid vehicle parts such as
the longitudinal members are affected in
an accident and the degree of deceleration
is sufficient.
Belt tensioners and belt force limiters
The front seat belts and the outer seat
belts in the rear are equipped with belt ten-
sioners.
!
Do not engage the seat belt tongue on the
front passenger seat if the seat is not occupied.
The belt tensioners could otherwise be activated
in an accident.
The load exerted by the seat belt is re-
duced if the seat belt is also equipped with
a belt force limiter.
The automatic comfort-fit feature reduces
the retraction force of the seat belts. This
results in the seat belt being more com-
fortable.
Only vehicles which have a rear bench seat
with electrically-adjustable outer seats*
have the automatic comfort-fit feature on
the seat belts in the rear compartment.
Belt tensioners tighten the seat belts in an
accident, pulling them close against the
body.
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Belt tensioners do not correct an incorrect
seat position or incorrectly worn seat belts.
Belt tensioners do not pull occupants back to-
wards the backrest.
The belt force limiters are fine-tuned to the
front airbags, which take over from the
seat belt a part of the restraining forces,
thus spreading the forces exerted by them
on the occupant over a greater area.