S 500 Coupe (140.070) V8-5.0L (119.970) (1995)
Side Air Bag: Description and Operation
Driver & Passenger Side Airbags
Purpose
The side airbag protects the upper torso and body of the driver and/or passenger from injury in the area of the door and B-pillar in the event of a side
collision. The protective effect of the side airbag is improved by the window airbag.
Design
The side airbag is protected in a housing containing the folded airbag, gas generator filled with solid propellant and squib. When the connector for the
side airbag is disconnected, the squib is short-circuited by a short-circuiting bridge.
Function
Function sequence
1
Upon exceeding the actuation threshold for the side airbag the emergency tensioning retractor control module with airbag sends an electric pulse
(firing pulse) to the squib in the gas generator.
2
The squib ignites the solid propellant in the gas generator. The solid propellant burns developing a gas which flows explosively under high
pressure into the airbag stored folded up in the side airbag housing.
3
Under the pressure of the gas flowing in the inflating airbag rips open the side airbag housing and the door liner at the planned breakpoint exiting
into the passenger compartment.
4
After approx. 20 ms the side airbag reaches its maximum volume.
5
After reaching the maximum volume the pressure in the side airbag begins to decrease immediately. The gas escapes from the side airbag through
a filter and the side airbag deflates.