Mercedes-Benz 600 SEL 1993 Owner's Manual page 51

Supplemental Restraint System
(SRS)
The SRS uses two crash severity
levels (thresholds) to activate
either the ETR or airbag or both.
Activation depends on the direc­
tion and severity of the impact,
exceeding the thresholds and
fastening of the seat belt.
Seat belt fastened
• first threshold exceeded:
ETR activates
• second threshold exceeded:
airbag also activates
Seat belt not fastened
• first threshold exceeded:
airbag activates, but not ETR
Driver and front passenger
systems operate independently
from each other.
Emergency Tensioning
Retractor (ETR)
The seat belts for the front seats
are equipped with emergency
tensioning retractors. These ten­
sioning retractors are located in
each belt's inertia reel and be­
come operationally ready with the
key in steering lock position 1
or 2.
The emergency tensioning re­
tractors are designed to activate
only when the seat belts are
fastened during frontal and front­
angled impacts exceeding the first
threshold of the SRS. They re­
move slack from the belts in such
a way that the seat belts fit more
snugly against the body restricting
its forward movement as much as
possible.
In cases of other frontal impacts,
roll-overs, certain side impacts,
rear collisions, or other accidents
without frontal forces, the emer­
gency tensioning retractors will not
be activated. The driver and
passengers will then be protected
by the fastened seat belts and
inertia reel in the usual manner.
For seat belt and emergency ten­
sioning retractor safety guidelines
see Safety Guidelines in Index.
49