Occupant Safety - Mercedes-Benz SL Roadster 2012 Owner's Manual

their seat belts correctly at all times, even if
the vehicle is equipped with airbags. The air-
bags are not deployed in all types of acci-
dents. For example, if the protective capacity
of correctly fastened seat belts is not
increased by deploying the airbags, the air-
bags will not deploy.
Airbag deployment only provides increased
protection if the seat belt is worn correctly.
The seat belt helps, firstly, to keep the vehicle
occupant in the best position in relation to the
airbag. Secondly, in a head-on collision, for
example, the seat belt restricts movement of
the vehicle occupant towards the point of
impact.
SRS (Supplemental Restraint System)
Introduction
SRS consists of:
the 6 SRS warning lamp
R
airbags
R
the airbag control unit with crash sensors
R
belt tensioners
R
belt force limiters
R
SRS reduces the risk of vehicle occupants
coming into contact with parts of the vehi-
cle's interior in the event of an accident. It can
also reduce the forces to which vehicle occu-
pants are subjected during an accident.
SRS warning lamp
G WARNING
If SRS is malfunctioning, restraint system
components may be triggered unintentionally
or might not be triggered at all in the event of
an accident with a high rate of vehicle decel-
eration. There is an increased risk of injury,
possibly even fatal.
Have SRS checked and repaired immediately
at a qualified specialist workshop.
SRS functions are checked regularly when
you switch on the ignition and when the

Occupant safety

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 read-
iness when the 6 SRS warning lamp goes
out while the engine is running.
A malfunction has occurred if:
the 6 SRS warning lamp does not light
R
up when the ignition is switched on
the engine is running and the 6 SRS
R
warning lamp does not go out after a few
seconds
the engine is running and the 6 SRS
R
warning lamp lights up again
Triggering of belt tensioners and air-
bags
During the first stage of a collision, the airbag
control unit evaluates important physical
data relating to vehicle deceleration or accel-
eration, such as:
duration
R
direction
R
magnitude
R
Based on the evaluation of this data, the air-
bag control unit triggers the belt tensioners in
the first stage.
If there is an even higher rate of vehicle decel-
eration or acceleration in a longitudinal direc-
tion, the front airbags are also deployed.
Your vehicle has adaptive, two-stage front air-
bags. The airbag control unit evaluates vehi-
cle deceleration or acceleration in the event
of a collision. In the first deployment stage,
the front airbag is filled with enough propel-
lant gas to reduce the risk of injuries. The
front airbag is fully deployed if a second
deployment threshold is reached within a few
milliseconds.
The belt tensioner and airbag triggering
thresholds are variable and are adapted to the
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