Subaru Outback (BR): Frontal airbag system operation

1) Driver’s side
2) Passenger’s side

The SRS airbag can function only when the ignition switch is in the “ON” position. The SUBARU advanced frontal airbag system is designed to determine the activation or deactivation condition of the front passenger’s SRS frontal airbag depending on the total load on the front passenger’s seat monitored by the front passenger’s occupant detection system weight sensor. For this reason, only the driver’s SRS frontal airbag may deploy in the event of a collision, but this does not mean failure of the system.

If the front sub sensors inside both front fenders and the impact sensors in the airbag control module detect a predetermined amount of force during a frontal collision, the control module sends signals to the airbag module(s) (only driver’s module or both driver’s and front passenger’s modules) instructing the module(s) to inflate the SRS frontal airbag(s). The driver’s and front passenger’s SRS frontal airbags use dual stage inflators. The two inflators of each airbag are triggered either sequentially or simultaneously, depending on the severity of impact in the case of the driver’s SRS frontal airbag and depending on the severity of impact and the total load on the seat in the case of the front passenger’s SRS frontal airbag.

After deployment, the SRS airbag immediately starts to deflate so that the driver’s vision is not obstructed. The time required from detecting impact to the deflation of the SRS airbag after deployment is shorter than the blink of an eye.

Both when only the driver’s SRS frontal airbag deploys and the driver’s and front passenger’s SRS frontal airbags deploy, the driver’s and front passenger’s seatbelt pretensioners operate at the same time.

Although it is highly unlikely that the SRS airbag would activate in a non-accident situation, should it occur, the SRS airbag will deflate quickly, not obscuring vision and will not interfere with the driver’s ability to maintain control of the vehicle.

When the SRS airbag deploys, a sudden, fairly loud inflation noise will be heard and some smoke will be released. These occurrences are a normal result of the deployment. This smoke does not indicate a fire in the vehicle.

CAUTION

Do not touch the SRS airbag system components around the steering wheel and dashboard with bare hands right after deployment. Doing so can cause burns because the components can be very hot as a result of deployment.

The driver’s SRS frontal airbag and front passenger’s SRS frontal airbag are designed to deploy in the event of an accident involving a moderate to severe frontal collision. It is basically not designed to deploy in lesser frontal impacts because the necessary protection can be achieved by the seatbelt alone. Also, they are basically not designed to deploy in side or rear impacts or in roll-over accidents because deployment of only the driver’s SRS frontal airbag or both driver’s and front passenger’s SRS frontal airbags would not help the occupant in those situations. The driver’s and front passenger’s SRS frontal airbags are designed to function on a one-time-only basis.

SRS airbag deployment depends on the level of force experienced in the passenger compartment during a collision. That level differs from one type of collision to another, and it may have no bearing on the visible damage done to the vehicle itself.

Examples of accident in which the driver’s/driver’s and front passenger’s SRS frontal airbag(s) will most likely deploy.

A head-on collision against a thick concrete wall at a vehicle speed of 12 to 19 mph (20 to 30 km/h) or higher activates only the driver’s SRS frontal airbag or both driver’s and front passenger’s SRS frontal airbags. The airbag(s) will also be activated when the vehicle is exposed to a frontal impact similar in fashion and magnitude to the collision described above.

Examples of the types of accidents in which it is possible that the driver’s/driver’s and front passenger’s SRS frontal airbag(s) will deploy.

Only the driver’s SRS frontal airbag or both driver’s and front passenger’s SRS frontal airbags may be activated when the vehicle sustains a hard impact in the undercarriage area from the road surface (such as when the vehicle plunges into a deep ditch, is severely impacted or knocked hard against an obstacle on the road such as a curb).

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