Hybrid filling technology
All airbags are equipped with hybrid inflators instead of the obsolete pyrotechnic gas generators, in which the airbags were inflated by detonating a pyrotechnic charge. In hybrid filling units, a self-contained pyrotechnic device is used to heat a compressed inert gas cylinder inside the unit. When the pressure exceeds the set value, the cylinder explodes and the gas enters the fabric cushion.
The advantage of the hybrid filling unit is the use of colder gas, which reduces the temperature of the pad and eliminates the post-expansion outburst of gas associated with solid pyrotechnic gas generators.
Two stage filling units
Driver and passenger airbags are equipped with two-stage inflation units. Each pillow uses two separate filling units with independent squibs that are connected to the pillow. This design optimizes airbag size, pressure, and rate of expansion to match vehicle design and impact force.
Driver and Passenger Protection Control Unit (RCM) evaluates the force of the collision, the tension of the seat belt and the proximity of the driver's seat to the steering wheel, and based on these data determines the deployment pattern of the airbags:
- At relatively low speeds, or if there is a small passenger next to the steering wheel, only the 'stage 1' inflator is deployed, inflating the airbag to about 70% of its capacity.
- In a collision at high speed, 'stage 1' is activated, and after a set delay - 'stage 2'; the airbag inflates completely, except when the driver is dangerously close to the steering wheel.
Driver airbag
The driver's airbag has a two-stage gas generator with a separate electrical connector for each stage. The notches in the inner surface of the casing form weak points where the casing ruptures in a predictable manner when the airbag is deployed.
Passenger airbag
Pos. | spare part no | Name |
1 | - | First stage - 70% of airbag volume |
2 | - | Second stage - full airbag volume |
The upper part of the cushion module is attached to the reinforcing cover on the instrument panel. The reinforcing cover has a single drop panel that is pushed out of place by the pad, tearing the control panel upholstery. The airbag has a two-stage gas generator with a separate electrical connector for each stage.
Passenger airbag switch
Vehicles delivered to certain countries are fitted with a key-activated passenger airbag switch. Turning the airbag switch changes the connection «masses» between two pins of the RCM connector. When the passenger's airbag is deactivated, a warning indicator will illuminate on the overhead console next to the rearview mirror.
The passenger airbag switch is activated by the emergency key, which is located on the instrument panel.
Passenger airbag deactivation indicator
When the switch is turned to the deactivate position, the RCM will deactivate the airbag and, if there is a passenger in the seat, will turn on the warning light.
Side airbags
The side airbag is attached to the backrest frame of each front seat and is located under the seat upholstery.
The side airbags vary according to the installation side and each consists of a plastic housing that houses the folded airbag and gas generator. The gas generator fuse is wired to a connector on the main seat harness connector block located under the front edge of the seat cushion. When deployed, the side airbag ruptures the plastic case and seatback upholstery.
Top side airbags
Pos. | spare part no | Name |
1 | - | curtain airbag housing |
2 | - | Guides for disclosure |
3 | - | gas generator |
4 | - | Rear stretch |
5 | - | blind |
6 | - | air chambers |
7 | - | Front webbing |
Side airbags protect the head in a side impact and also help prevent unbelted occupants from falling out of the vehicle through open or broken windows in a rollover.
The sunblind opens with a single filling unit located behind the rear seats; this fills five separate cavities to protect the heads of passengers in the event of a side impact or rollover. Steel rails ensure that the curtain unfolds correctly, while straps at the front and back ensure it is kept taut.
Deployment of the curtain airbags is deliberately slowed down so that it remains open until after the vehicle is rolled over.
Airbag warning lamp
The airbag warning indicator consists of a red LED that illuminates the SRS icon on the instrument panel.
The airbag warning indicator is controlled by a message received by the instrument cluster over the high speed CAN bus from the RCM. The RCM sends a signal to turn on the airbag warning indicator if a malfunction is detected, and also illuminates the indicator for approximately 6 seconds during the test of instrument panel warning lamps at the beginning of each ignition cycle.
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