Driver airbag, function - GF91.60-P-4001-02GC

WARNING: This page does not describe the selected car, but rather 42 other vehicles, including the 1999 Mercedes-Benz S600, 1999 Mercedes-Benz S500, 1999 Mercedes-Benz S420, 1999 Mercedes-Benz S320, and 1999 Mercedes-Benz CL600. However, it is still accessible from the selected car via links, so may be relevant.

Models 129, 140, 168, 170, 202, 208, 210, 215, 220

Function sequence

When the actuation threshold for the driver airbag is exceeded an electric pulse (triggering pulse) is transmitted to the squib in the gas generator by the emergency tensioning retractor and airbag control module.
The squib ignites the solid fuel in the gas generator. The solid fuel combusts developing a gas which explodes under high pressure into the airbag through a filter.
The airbag folded together on the gas generator inflates and the pressure of the gas flowing in tears open the steering wheel cushion at a predetermined breaking point

Fig 1: Identifying Driver Airbag, Function (1 Of 3)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
While continuously inflating the airbag exits from the predetermined breaking point inflating to its maximum volume.

Fig 2: Identifying Driver Airbag, Function (2 Of 3)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
After approx. 45 ms the airbag reaches its maximum volume.
When the maximum volume is reached the pressure in the airbag starts decreasing immediately. The gas escapes from the airbag through a filter and the airbag deflates.

Fig 3: Identifying Driver Airbag, Function (3 Of 3)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.