It is therefore not possible to cover all
conceivable types of collisions and collision angles
that would trigger airbags. Some important
factors for the triggering of airbags are the
nature of the object (hard or soft) against which
the impact occurs, the angle of collision and the
speed of the vehicle.
Description and operation of
airbags
Please note at the beginning of this
chapter
The airbag can protect vehicle occupants in the
event of frontal and side collisions by
cushioning their displacement in the direction of
impact.
Airbags only supplement the function of
automatic three-point seat-belts in certain
accidents where vehicle deceleration is high
enough for the airbags to deploy. The airbags
are only deployed once and only under certain
circumstances.
The seat-belts are always there to provide
protection in situations where the airbags
should not or have already deployed. For
example, when a vehicle, after a first collision,
collides with another vehicle or is hit by another
vehicle.
When an airbag is triggered, a gas generator
inflates it. This ruptures the relevant airbag
covers and the airbag deploys with great force
in a matter of milliseconds in its respective
deployment zone. When the occupant, with the
seat belt fastened, dives into the deployed
airbag, gas is released from the airbag to slow it
down and cushion the impact. This can reduce
the risk of serious injury or death. Other injuries
such as swelling, contusions, burns or dents
caused by the airbag being deployed cannot be
ruled out. Frictional heat may also be produced
when the airbag is deployed during
The airbag system is part of the overall passive
safety system of the vehicle. The airbag system
can only provide optimum protection in
combination with properly fitted seat belts and a
correct seating position for the occupants → p.
54.
deployment.
Airbags do not protect the arms and lower
body. Exception: in vehicles fitted with a knee
airbag, the driver's knee area is protected.
Vehicle security system components
The following vehicle equipment together make
up the vehicle's safety system to reduce the
risk of serious or fatal injury. Some equipment
may not be fitted to the vehicle as an option or
may not be available in some countries.
The most important factors involved in
triggering the airbags are the type of accident,
the angle of collision, the speed of the vehicle
and the nature of the object into which the
vehicle collides. Therefore, the airbags do not
deploy in any collision that causes per- ceptible
damage to the vehicle.
– Optimised seat belts in all seating positions
– Pretensioners with pre-tensioning function on
driver's and front passenger seat belts
The airbag system is triggered by the degree of
deceleration which the vehicle experiences as a
result of an impact and which is recorded by an
electronic control unit. If the deceleration rate
value is below the reference value programmed
in the control unit, the airbags will not be
triggered even though the vehicle may sustain
significant damage in an accident. Damage to
the vehicle in an accident, the absence of such
damage or the cost of repairing it is not
– If necessary, pre-tensioners on the rear side
seat belts in combination with side airbags
– Force limiters on the driver's and front
passenger's seat belts and, where
appropriate, on the rear rear rear seat belts
– Front seatbelt height adjusters for front
seat belts
– Front airbags for the driver and passenger
necessarily an indication of whether or not an
airbag should have been triggered. Since
different crash situations can vary greatly from
one another, it is impossible to define a palette
of reference speeds and values. For
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Instruction manual