Deploy Supplemental Restraint System, Basic Function - GF91.60-P-1003A
Model all (CAR)
Overview
This document contains the following information:
- General
- Function requirement
- Function
General
The SRS evaluates various input factors and deploys the corresponding restraint equipment in the event of an accident.
Function requirement
- Circuit 15R on
Function
The restraint equipment is actuated depending on:
- Type and severity of the impact
- Status of seat belts (fitted or not fitted)
- Occupation of front passenger seat
In the following table, component parts marked with "X" are those that can be ultimately triggered for the respective accident scenarios:
| Frontal impact | Side impact | Rear impact | Rollover | |
|---|---|---|---|---|
| Driver airbag | X | - | - | - |
| Passenger airbag | X | - | - | - |
| Kneebag | X | - | - | - |
| Center airbag (vehicles with center airbag) | - | X | - | - |
| Front side airbag | - | X | - | - |
| Rear passenger compartment side | - | X | - | - |
| airbag (vehicles with side airbag in the rear) | ||||
| Rear airbag (vehicles with tubular-structure airbag for rear passengers) | X | - | - | - |
| Cushionbag (vehicles with reclining rear seat) | X | - | - | - |
| Belt airbag (vehicles with belt airbag for | X | - | - | - |
| rear passengers) | ||||
| Window airbag | X | X | - | X |
| Front ETR | X | X | X | X |
| Rear emergency tensioning retractor | X | X | X | X |
| Front seat belt end-fitting tensioner | X | - | - | - |
| (Canada version or USA version) | ||||
| Front seat belt force limiter (Canada | X | - | - | - |
| version, USA version or Japan version) | ||||
| PRE-SAFE® Impulse (vehicles with driver seat belt buckle with integrated tensioning function) | X | |||
| PRE-SAFE® Impulse side (vehicles with PRE-SAFE® Impulse side) | - | X | - | - |
| Gas generator inerting system (vehicles | X | - | - | - |
| with alternative refrigerant and spark-ignition engine) | ||||
| 12 V on-board electrical system battery pyrofuse (hybrid vehicles) | X | - | - | - |
| Pyrofuse, circuit 30c (vehicles with 48 V technology, hybrid or electric vehicles) | X | X | X | X |
The following conditions are taken into account in the case of frontal impact:
- Position of driver and front passenger seat (Canada version or USA version):
The SRS decides the trigger point of the driver and front passenger airbag depending on the position of the front seats.
The position of the front seats is recorded by a sensor at the guide rail of each front seat.
- Front passenger seat occupancy status:
- Front passenger seat unoccupied: The SRS does not deploy any restraint equipment on the front passenger side.
- Child seat detected on front passenger seat and seat belt not fastened: The SRS does not deploy any restraint equipment on the front passenger side.
- Child seat detected on front passenger seat and seat belt fastened: The SRS triggers the seat belt tensioner on the front passenger side.
- Person detected on front passenger seat and seat belt not fastened: The SRS triggers the front passenger airbag.
- Driver/front passenger seat belt buckle status:
If the seat belt is not fastened, the SRS does not deploy any seat belt relevant restraint equipment on the driver or front passenger side.
- Status of seat belt buckles in rear:
If the seat belt is not fastened, the SRS always triggers all restraint equipment in the rear passenger compartment If, depending on the equipment installed, diagnosis-capable seat belt buckles are installed, the SRS only triggers when the seat belt buckle is inserted.
- Rear airbags' deactivation status (vehicles with tubular-structure airbag for rear passengers, except Canada version and except USA version):
The rear airbags are only triggered if they have not been deactivated beforehand using the corresponding menu in the head unit.
The following conditions are taken into account in the event of a side impact:
- Front passenger seat occupancy status:
- Front passenger seat unoccupied: The SRS does not deploy any restraint equipment on the front passenger side.
- Child seat or person detected on front passenger seat and seat belt not fastened: The SRS does not trigger the seat belt tensioner on the front passenger side.
- Driver seat belt buckle status:
If the seat belt is not fastened, the SRS does not trigger the seat belt tensioner on the driver's side.
- Status of seat belt buckles in rear:
If the seat belt is not fastened, the SRS always triggers all restraint equipment in the rear passenger compartment If, depending on the equipment installed, diagnosis-capable seat belt buckles are installed, the SRS only triggers when the seat belt buckle is inserted.
The following conditions are taken into account in the event of a rear impact:
- Driver/front passenger seat belt buckle status:
If the seat belt is not fastened, the SRS does not deploy any restraint equipment on the driver or front passenger side.
- Status of seat belt buckles in rear:
If the seat belt is not fastened, the SRS always triggers all restraint equipment in the rear passenger compartment If, depending on the equipment installed, diagnosis-capable seat belt buckles are installed, the SRS only triggers when the seat belt buckle is inserted.
The following conditions are taken into account in the event of a vehicle rollover:
- Driver/front passenger seat belt buckle status:
If the seat belt is not fastened, the SRS does not deploy any restraint equipment on the driver or front passenger side.
- Status of seat belt buckles in rear:
If the seat belt is not fastened, the SRS always triggers all restraint equipment in the rear passenger compartment.
If, depending on the equipment installed, diagnosis-capable seat belt buckles are installed, the SRS only triggers when the seat belt buckle is inserted.
The status of the seat belts (fastened or unfastened) is recorded by a switch in the respective seat belt buckle.
With two-stage airbags, their deployment can be regulated.
Vehicles with alternative refrigerant and spark-ignition engine
In the event of a severe frontal impact, the refrigerant lines of the air conditioning system may be damaged. The leaking refrigerant together with the ambient air forms a combustible mixture. The inerting system ensures that this refrigerant/air mixture is kept separated from the hot engine parts. The hot engine parts are also effectively cooled. The inert gas argon is stored in the inerting system's gas cylinder. The targeted release of inert gas at the appropriate hot spots can counteract the potential ignition of the refrigerant/air mixture.
Vehicles with 48 V technology, hybrid or electric vehicles
In the event of an accident, the electric lines and components may be damaged. To avoid a fire hazard caused by a short circuit, the following pyrofuses are deployed:
- Pyrofuse on battery terminal of on-board electrical system battery (hybrid vehicles): Disconnects the battery line from the rest of the on-board electrical system.
- Pyrofuse 48 V or high voltage components: Disconnects the control terminal line (circuit 30 c). This shuts off the respective system.
| Function schematics | |||
| Function schematic, trigger Supplemental Restraint System | Model 118, 177, 243, 247 | PE91.60-P-2501-97A | |
| Model 167Model 293 | PE91.60-P-2501-97B | ||
| Model 206 | PE91.60-P-2501-97E | ||
| Model 213, 238, 257, 290 as of model year 2021 | PE91.60-P-2501-97D | ||
| Model 223 | PE91.60-P-2501-97C | ||
| Model 297 | PE91.60-P-2501-97F | ||
| Subsystems | |||
| Front passenger seat occupancy recognition, basic function | GF91.60-P-1006A | ||
| Control units | |||
| Supplemental restraint system control unit, basic function | GF91.60-P-9890A | ||
| Components | |||
| Inerting system, basic function | Model all (CAR) with code 2U8 (Alternative refrigerant) with gasoline engine |
GF86.10-P-2003A | |
| Seat belt end-fitting tensioner, basic function | Model all (CAR) with code 460 (Canada version) Model all (CAR) with code 494 (US version) |
GF91.40-P-2025A | |
| Seat belt buckle switch, basic function | GF91.60-P-2009A | ||
| Seat position Hall sensor, basic function | Model all (CAR) with code 460 (Canada version) Model all (CAR) with code 494 (US version) |
GF91.60-P-2013A | |
| Pyrofuse, basic function | Vehicles with code B01 (48V technology), hybrid vehicles, electric vehicles | GF91.60-P-2014A | |
| Seat belt tensioner, basic function | GF91.60-P-2015A | ||
| Driver airbag, basic function | GF91.60-P-2020A | ||
| Front passenger airbag, basic function | GF91.60-P-2021A | ||
| Side airbag, basic function | GF91.60-P-2022A | ||
| Window airbag, basic function | GF91.60-P-2023A | ||
| Knee airbag, basic function | GF91.60-P-2024A | ||
| Belt airbag, basic function | Model all (CAR) with code 306 (Rear seat belt with integrated airbag) |
GF91.60-P-2026A | |
| Cushionbag, basic function | Model all (CAR) with code 453 (Rear reclining seat) |
GF91.60-P-2028A | |
| Center airbag, basic function | Model all (CAR) with code 325 (Center airbag) |
GF91.60-P-2029A | |
| Rear airbag, basic function | Model all (CAR) with code 302 (Tubular structure airbag for rear occupants) |
GF91.60-P-2030A |