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GF91.60-P-0002-08PMA Supplemental Restraint System (SRS) Deployment Logic



GF91.60-P-0002-08PMA Supplemental Restraint System (SRS) Deployment Logic

In the event of an accident the restraint systems control unit (N2/7) decides, depending upon the severity of the accident, which airbag and emergency tensioning retractor units should be triggered. In doing so it considers the following input variables:
- Sidebag and windowbag sensor, left (A53/1)
- Sidebag and windowbag sensor, right (A54/1)
- Driver-side frontal acceleration sensor (B48/1)
- Passenger-side frontal acceleration sensor (B48/2)
- Driver seat belt buckle restraint systems switch (S68/3)
- Front passenger seat belt buckle restraint systems switch (S68/4)

A message is sent via the Controller Area Network-Bus Class B (interior) (CAN-B) from the WSS (Weight Sensing System) control unit (N2/13) concerning the status of the front passenger seat. The status is determined using the following sensors:
- Pressure sensor (B48/4)
- Belt tension sensor (B48/3)

Emergency opening of the central locking (CL) system
A crash sensor is installed in the rear SAM control unit with fuse and relay module (N10/2). If the vehicle acceleration is > 60 m/s 2 then a signal for emergency opening is sent via the CAN-B following a waiting time of 8 to 11 s to each door control unit.

The signal is sent to the following control units:
- Left front door control module (N69/1)
- Right front door control module (N69/2)
- Left rear door control unit (N69/3) (except model 203.7)
- Right rear door control unit (N69/4) (except model 203.7)

Flashing alarm
In the event of a crash, the hazard warning system is switched on automatically. To this end the restraint systems control unit (N2/7) sends the crash signal via the CAN-B to the rear SAM control unit with fuse and relay module (N10/2), which acts as a turn-signal master. The hazard warning system can be switched off at any given time using the hazard warning system switch (N72/1s5).

As a "function check" is not possible for the supplemental restraint system (SRS), a description of the individual triggering strategies is not provided in this section. Beyond this, the triggering strategies are also subject to modifications, such as, e.g. those which result from new knowledge gained in the area of accident research.