Function; Belt Force Limiters; Emergency Tensioning Devices - Mercedes-Benz M-Class Operator's Manual

and
if a vehicle speed of 15 mph (25 km/h) is
R
exceeded, the 7 seat belt warning lamp
begins to flash. A warning tone also sounds
with increasing intensity for a maximum of
60 seconds or until the driver or front
passenger have fastened their seat belts.
If the driver/front passenger unfasten their
seat belt while the vehicle is in motion, the
7 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases even if the driver or
front-passenger seat belt has still not been
fastened after 60 seconds. The 7 seat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated. The 7 seat
belt warning lamp flashes again if the vehicle
speed exceeds 15 mph (25 km/h).
The 7 seat belt warning lamp only goes
out if:
both the driver and the front passenger
R
have fastened their seat belts.
or
the vehicle is stationary and a door is open.
R
i
For more information on the 7 seat
belt warning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belts" ( page 317).
Y
Emergency Tensioning Devices, seat

belt force limiters

G
WARNING
Pyrotechnic Emergency Tensioning Devices
that have been deployed are no longer
operational and are unable to perform their
intended protective function. This poses an
increased risk of injury or even fatal injury.
Therefore, have pyrotechnic Emergency
Tensioning Devices which have been
triggered immediately replaced at a qualified
specialist workshop.
Occupant safety
! If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise, the Emergency
Tensioning Device could be triggered in the
event of an accident.
i
Vehicles with PRE-SAFE
Tensioning Devices that are triggered by an
electric motor can be deployed as often as
desired and do not need to be replaced.
The front seat belts and the outer seat belts
in the rear are equipped with Emergency
Tensioning Devices and seat belt force
limiters.
The Emergency Tensioning Devices on the
driver's and front-passenger seat consist of
pyrotechnic belt buckle tensioners and belt
anchor installation tensioners that are
triggered together. The belt buckle tensioner
is mounted on the B-pillar and the belt anchor
installation is mounted on the side of the seat.
After deploying, both tensioners must always
be replaced.
Emergency Tensioning Devices tighten the
seat belts in an accident, pulling them close
against the body.
Emergency Tensioning Devices do not
correct incorrect seat positions or incorrectly
fastened seat belts.
Emergency Tensioning Devices do not pull
vehicle occupants back towards the
backrest.
When triggered, seat belt force limiters help
to reduce the force exerted by the seat belt
on the vehicle occupant.
The seat belt force limiters for the front seats
are synchronized with the front air bags,
which take on a part of the deceleration force.
This results in the force exerted on the
occupant being distributed over a greater
area.
59
®
: Emergency
Z