GF91.60-P-2001RC Deploy Supplemental Restraint System, Function

GF91.60-P-2001RC Deploy Supplemental Restraint System, Function

General function requirements
^ Circuit 15R On

Triggering supplemental restraint system (SRS), general
The SRS continuously monitors the occupation status of the front passenger seat, the status of the seat belts (buckled or not buckled) and adjusts its triggering behavior with the help of this information.

The trigger SRS function consists of the following subfunctions:
^ Function sequence for detecting occupied status of front passenger seat
^ Function sequence for detecting status of seat belts
^ Impact detection function sequence
^ Frontal impact function sequence
^ Side impact function sequence
^ Rear end collision function sequence
^ Rollover function sequence

Function sequence for detecting occupied status of front passenger seat
The restraint systems control unit (N2/7) receives the corresponding information from the following components:
- Front passenger seat occupied and child seat recognition sensor (B48) (without code (494) USA version)
- Weight sensing system (WSS) control unit (N110) (for code (494) USA version)

Function sequence for detecting status of seat belts
The driver seat belt buckle restraint systems switch (S68/3) or the front passenger seat belt buckle restraint systems switch (S68/4) is actuated by the belt latch which is inserted into the seat belt buckle. This is read in directly by the restraint systems control unit.

Impact detection function sequence
The restraint systems control unit determines the acceleration acting on the vehicle with the aid of its integrated sensor and the following sensors:
- Drive sidebag sensor (A53)
- Front passenger sidebag sensor (A54)
- Driver-side frontal acceleration sensor (B48/1)
- Passenger-side frontal acceleration sensor (B48/2)

With the aid of this sensor system, the SRS is able to distinguish between the following types of impacts:
- Head-on collision
- Side-on collision
- Rear end collision
- Roll-over

Frontal impact function sequence
A frontal impact is detected by the restraint systems control unit via the signals from the following components:
- Sensor integrated into the restraint systems control unit
- Driver-side frontal acceleration sensor
- Passenger-side frontal acceleration sensor

The restraint equipment is triggered depending on the severity of the impact, the occupation of the front passenger seat and the status of the seat belts.

The following squibs can be ignited (at most):
- Passenger airbag squib 1 (R12/4)
- Passenger airbag squib 2 (R12/5)
- Driver airbag squib 1 (R12/13)
- Driver airbag squib 2 (R12/14)
- Front passenger kneebag squib (R12/24) (for code (494) USA version)
- Driver kneebag squib (R12/25) (for code (494) USA version)
- Drive buckle ETR squib (R46)
- Front passenger ETR squib (R46/1)

The following situations are taken into account:
- Occupied state of the front passenger seat:
The restraint systems control unit uses the current occupancy to decide whether to suppress the front passenger airbag unit or to use 1-stage or 2-stage deployment.

- Driver seat belt buckle status:
If the driver seat belt buckle restraint systems switch detects that a belt latch is not inserted into the seat belt buckle, the driver airbag unit with advanced ignition timing is triggered instead of the driver buckle emergency tensioning retractor unit.

- Front passenger seat belt buckle status:
If the front passenger seat belt buckle restraint systems switch detects that a belt latch is not inserted into the seat belt buckle, the front passenger airbag unit with advanced ignition timing is triggered instead of the front passenger buckle emergency tensioning retractor unit.

This only applies, however, if the front passenger seat is known to be occupied. If the seat is not occupied, neither the buckle emergency tensioning retractor nor the front passenger airbag unit are deployed.

Side impact function sequence
A side impact is detected by the restraint systems control unit via the signals from the following components:
- Sensor integrated into the restraint systems control unit
- Driver sidebag sensor
- Front passenger sidebag sensor

The restraint equipment is triggered depending on the severity of the impact and the occupation of the front passenger seat.

The following squibs can be ignited (at most):
- Driver sidebag squib (R12/9)
- Front passenger sidebag squib (R12/10)
- Driver buckle ETR squib
- Front passenger buckle ETR squib

The sidebags are designed as head/thorax bags and have a volume that is up to ten liters greater than conventional sidebags. They are used to replace the combination of windowbag and sidebag.

The following situations are taken into account:
- The restraint systems control unit makes its decision regarding triggering the front passenger sidebag unit based on the current occupancy of the front passenger seat.
- The restraint systems control unit bases its decision regarding triggering the buckle emergency tensioning retractors on the status of the seat belt buckles. The buckle emergency tensioning retractors are not triggered if belt latches are not inserted.

Only the sidebag on the crash side is triggered.
Only the buckle emergency tensioning retractor on the side opposite the crash side is triggered.

Rear end collision function sequence
A rear end collision is detected by the restraint systems control unit via the signals from the following components:
- Sensor integrated into the restraint systems control unit
- Driver sidebag sensor
- Front passenger sidebag sensor
- Driver-side frontal acceleration sensor
- Passenger-side frontal acceleration sensor

The restraint equipment is triggered depending on the severity of the impact and the status of the seat belts.
The following squibs can be ignited (at most):
- Driver buckle ETR squib
- Front passenger buckle ETR squib

The following situations are taken into account:
- Driver seat belt buckle status:
If the driver seat belt buckle restraint systems switch detects that a belt latch is not inserted into the seat belt buckle, the driver buckle emergency tensioning retractor unit is not triggered.

- Front passenger seat belt buckle status:
If the front passenger seat belt buckle restraint systems switch detects that a belt latch is not inserted into the seat belt buckle, the front passenger buckle emergency tensioning retractor unit is not triggered.

Rollover function sequence
A rollover is detected by the restraint systems control unit via the signals from the following components:
- Sensor integrated into the restraint systems control unit
- Driver sidebag sensor
- Front passenger sidebag sensor
- Driver-side frontal acceleration sensor
- Passenger-side frontal acceleration sensor

The following squibs can be ignited (at most):
- Driver sidebag squib
- Front passenger sidebag squib
- Driver buckle ETR squib
- Front passenger buckle ETR squib

The following situations are taken into account:
- Driver seat belt buckle status:
If the driver seat belt buckle restraint systems switch detects that a belt latch is not inserted into the seat belt buckle, the driver buckle emergency tensioning retractor unit is not triggered.

- Front passenger seat belt buckle status:
If the front passenger seat belt buckle restraint systems switch detects that a belt latch is not inserted into the seat belt buckle, the front passenger buckle emergency tensioning retractor unit is not triggered.