Mercedes-Benz SL-Class 2015 - Manual (Page 67)

should leave the vehicle as soon as it is safe to
do so, or open the window.
Air bags and pyrotechnic seat belt tensioners
contain perchlorate material, which may
require special handling or environmental
protection measures. Check with your local
government’s disposal guidelines. California
residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm.
Method of operation
During the first stage of a collision, the
restraint system control unit evaluates impor-
tant physical data relating to vehicle deceler-
ation or acceleration, such as:
R Duration
R Direction
R
Intensity
Based on the evaluation of this data, the
restraint system control unit triggers the belt
tensioners in the event of a frontal or rear
collision.
An Emergency Tensioning Device can only be
triggered if:
R the ignition is switched on
R the restraint system components are ready
for operation, see “Restraint system warn-
ing lamp” (
Y
page 51)
R the belt tongue is inserted into the buckle
on the respective front seat
If the restraint system control unit detects a
high accident severity, additional compo-
nents of the restraint system are activated
independently of one another in certain fron-
tal collision situations:
R
Front air bags as well as driver's and front-
passenger kneebag
Depending on the person occupying the front-
passenger seat, the front-passenger air bag is
activated or deactivated. The front-passenger
front air bag can only be deployed in an acci-
dent if the PASSENGER AIR BAG OFF indica-
tor lamp is off. Observe the information on the
PASSENGER AIR BAG OFF indicator lamp
(
Y
page 51).
Your vehicle has two-stage front air bags.
During the first deployment stage, the front
air bag fills with propellant gas which reduces
the risk of injury. The second stage is then
triggered within milliseconds, filling the front
air bag with the maximum amount of propel-
lant gas.
The deployment thresholds for the Emer-
gency Tensioning Devices and air bags are
calculated on the basis of the vehicle decel-
eration or acceleration occurring at various
points in the vehicle. This process is pre-emp-
tive in nature. The air bag must be deployed
on time, at the start of the collision.
The rate of vehicle deceleration or accelera-
tion and the direction of the force are essen-
tially determined by:
R distribution of the force during the impact
R collision angle
R deformation characteristics of the vehicle
R characteristics of the object with which the
vehicle has collided
Factors which can only be seen and measured
after the collision has occurred do not play a
decisive role in the deployment of an airbag,
nor do they provide an indication of air bag
deployment.
The vehicle may be considerably deformed
without an air bag being deployed. This is the
case if only relatively easily deformable parts
have been hit and a high rate of deceleration
has not been reached. Conversely, an air bag
may be deployed even though the vehicle suf-
fers only minor deformation. This is the case
if, for example, very rigid vehicle parts such as
the longitudinal body members are hit in an
accident and the rate of deceleration is suffi-
cient.
Occupant safety
65
Safety
Z