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GF91.60-P-0002PP Supplemental Restraint System (SRS), Function




GF91.60-P-0002PP Supplemental Restraint System (SRS), Function


Deployment characteristics shown on Model 203.0







The figures depict the deployment of various airbag and emergency tensioning retractor units in various types of accidents:
- In the event of rear-impact collisions as well as minor front- impact collisions, only the belt tensioning systems are deployed, with more severe head-on crashes the front airbags are also deployed.
- If the transverse acceleration threshold is exceeded in the event of a side impact the relevant sidebags and windowbags are triggered.

The Supplemental Restraint System (SRS) serves to protect vehicle occupants from injury in various types of accidents.
The vehicle's SRS comprises the following airbag and belt tensioning units:
- Driver airbag (2-stage) with driver airbag squib 1 (R12/13) and driver airbag squib 2 (R12/14)
- Front passenger airbag (2-stage) with front passenger airbag squib 1 (R12/4) and front passenger airbag squib 2 (R12/5)
- Left front sidebag with left front sidebag squib (R12/20)
- Right front sidebag with right front sidebag squib (R12/21)
- Left rear sidebag (except Model 203.7) with rear left sidebag squib (R12/11)
- Right rear sidebag (except Model 203.7) with right rear sidebag squib (R12/12)
- Left rear windowbag with left rear windowbag squib (R12/22)
- Right rear windowbag with right rear windowbag squib (R12/23)
- Driver emergency tensioning retractor unit with driver ETR squib (R12/1)
- Front passenger emergency tensioning retractor unit with front passenger ETR squib (R12/2)
- Left rear belt tensioning unit with rear left ETR squib (R12/6)
- Right rear emergency tensioning retractor unit with right rear ETR squib (R12/7)

The restraint systems control unit (N2/7) senses crash type and severity and deploys precisely those airbag and ETR units necessary to provide optimum passenger protection.
The data received by the front passenger seat occupied and child seat recognition sensor (B48) and the statuses of the driver seat belt buckle restraint systems switch (S68/3) and the front passenger seat belt buckle restraint systems switch (S68/4) are taken into consideration for triggering.
At the same time as the respective airbag and emergency tensioning retractor units are deployed, the restraint systems control unit (N2/7) issues a crash signal to various control units:
- For shutting off the engine at the motor electronics control unit (N3/10) or the CDI control unit (N3/9). The signal reaches the EIS control unit (N73) via the Controller Area Network Bus Class B (interior) (CAN-B) and from there it is sent via the Controller Area Network Bus Class C (engine compartment) (CAN-C) to the motor electronics control unit (N3/10) or the CDI control unit (N3/9)
- With code (855) TELE AID for initiating an emergency call to the D2B telephone and TELE AID transmitter/receiver (A35/17). The signal is sent on a discrete line to the front SAM control unit with fuse and relay module (N10/1), from where it is relayed to the D2B telephone and TELE AID transmitter/ receiver (A35/17)
- For emergency opening to the left front door control unit (N69/1)
- For emergency opening to the right front door control unit (N69/2)
- For emergency opening to the left rear door control unit (N69/3) (except model 203.7)
- For emergency opening to the right rear door control unit (N69/4) (except model 203.7)
- To the rear SAM control unit with fuse and relay module for actuating the hazard warning system (N10/2)

System monitoring
System malfunctions are indicated by the airbag indicator and warning lamp (A1e15) and the multifunction display (A1p13) in the instrument cluster (A1).
In order to do this the instrument cluster (A1) receives the relevant message from the restraint systems control unit (N2/7) via the CAN-B.

Seat occupied recognition sensor and automatic child seat recognition
The front passenger seat occupied and child seat recognition system (B48) prevents the airbag and belt tensioning units on the front passenger side from being triggered under certain conditions.
The function of the child seat recognition system and the deactivation of the front passenger airbag by the automatic child seat recognition are indicated by the automatic child seat recognition airbag OFF indicator (N72/1e1).

Hazard warning lights in the event of a crash
In the event of a crash, the hazard warning system is switched on automatically. It can be switched off by pressing the hazard warning switch (N72/1s5).

Diagnosis
Diagnosis is performed using STAR DIAGNOSIS.
The airbag units bear the label "SRS Airbag" at their installation location.

Disposal
When handling and disposing of the airbag and emergency tensioning retractor units, the corresponding safety and disposal information in the work instructions must be observed without fail.

The restraint systems control unit (N2/7) has its own capacitor. If the battery is disconnected (self-sufficiency case) the entire system is supplied with voltage for at least 150 ms.