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Q: What determines if the air bags will deploy or not?

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What determines if the air bags will deploy or not?

A: While it might seem like your air bags shou...

While it might seem like your air bags should deploy during every accident, that’s actually not the case. Some aren’t severe enough to warrant it, while in other situations, deploying the air bags might actually cause injury if someone isn’t properly seated in the car.

Your air bag system is monitored and controlled by the computer and a network of sensors. The sensors read the severity and location of an impact and then send that information to the computer. The computer then determines if the criteria warrant deploying the air bags. There are a couple of other things that you should know here, as well:

  • You must be going faster than 12 – 18 MPH for any air bag to deploy. If you’re driving slower than this, the air bags will not inflate.

  • Even if the air bags are not inflated, it’s possible that your seat belt pretensioners will be activated. Have your belts inspected after every collision.

  • If there isn’t a passenger sitting in the front seat, the passenger front air bag will not inflate. It also won’t inflate if the passenger is not adult sized (a child, for instance).

  • Side and side curtain air bags only deploy in some side impact situations (the collision has to have sufficient force to trigger the system).

  • The side curtain air bags should deploy in a rollover situation.

  • The front air bags may inflate if your car strikes something severely with the undercarriage.

  • Some angled front impacts may not set off any air bags.


  • If an air bag has been deployed, it must be replaced. They cannot be reused.

  • Never attempt to replace an air bag on your own.

  • Never rely on the air bags alone. Always wear your seat belt and make sure everyone in the vehicle is wearing theirs.

  • Always have your seat belts inspected after an accident to determine if the pretensioners were deployed (even if the air bags didn’t go off).

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