Mercedes-Benz G-Class Operator's Manual page 46

Occupant safety
44
Method of operation
During the first stage of a collision, the restraint
system control unit evaluates important physi-
cal data relating to vehicle deceleration or accel-
eration, such as:
duration
R
direction
R
intensity
R
Based on the evaluation of this data, the
restraint system control unit triggers the Emer-
gency Tensioning Devices during a frontal or
rear collision.
An Emergency Tensioning Device can only be
triggered, if:
the ignition is switched on
R
the components of the restraint system are
R
operational; see "Restraint system warning
lamp" ( page 35)
Y
the belt tongue is engaged in the buckle on
R
the respective front-passenger seat
The Emergency Tensioning Devices in the rear
compartment are triggered independently of the
lock status of the seat belts.
If the restraint system control unit detects a
more severe accident, further components of
the restraint system are activated independ-
ently of each other in certain frontal collision
situations:
Driver's air bag
R
Front-passenger front air bag
R
The front-passenger front air bag is activated or
deactivated depending on the person on the
front-passenger seat. The front-passenger front
air bag can only deploy in an accident if the
PASSENGER AIR BAG OFF indicator lamp is off.
Observe the information on the PASSENGER AIR
BAG OFF indicator lamp (
Your vehicle has a two-stage driver's air bag.
During the first deployment stage the driver's air
bag fills with sufficient propellant gas to reduce
the risk of injuries. The front air bag is fully
deployed with the maximum amount of propel-
lant gas if a second deployment threshold is
reached within a few milliseconds.
The activation threshold of the Emergency Ten-
sioning Devices and the air bag are determined
by evaluating the rate of vehicle deceleration or
acceleration which occurs at various points in
the vehicle. This process is pre-emptive in
nature. Deployment should take place in good
time at the start of the collision.
page 35).
Y
The rate of vehicle deceleration or acceleration
and the direction of the force are essentially
determined by:
the distribution of forces during the collision
R
the collision angle
R
the deformation characteristics of the vehicle
R
the characteristics of the object with which
R
the vehicle has collided
Factors which can only be seen and measured
after a collision has occurred do not play a deci-
sive role in the deployment of an air bag. Nor do
they provide an indication of air bag deploy-
ment.
The vehicle can be deformed considerably, with-
out an air bag being deployed. This is the case if
only parts which are relatively easily deformed
are affected and the rate of deceleration is not
high. Conversely, air bags may be deployed even
though the vehicle suffers only minor deforma-
tion. This is the case if, for example, very rigid
vehicle parts such as longitudinal body mem-
bers are hit, and sufficient deceleration occurs
as a result.
If the restraint system control unit detects a side
impact or if the vehicle rolls over, the applicable
components of the restraint system are activa-
ted independently of each other depending on
the apparent type of accident.
Side impact air bag and pelvis air bag on the
R
side of impact, independently of the Emer-
gency Tensioning Device and the use of the
seat belt
The side impact air bag on the front-
passenger side deploys under the following
conditions:
BabySmart™ detects that the front-
-
passenger seat is occupied or
the belt tongue is engaged in the belt
-
buckle of the front-passenger seat
Window curtain air bag on the side of impact,
R
independently of the use of the seat belt and
independently of whether the front-
passenger seat is occupied
Emergency Tensioning Devices, if the system
R
determines that deployment can offer addi-
tional protection in this situation
Window curtain air bags on the driver's and
R
front-passenger side in certain situations
when the vehicle rolls over, if the system
determines that deployment can offer addi-
tional protection to that provided by the seat
belt