GM Service Manual Online
For 1990-2009 cars only

An air bag is designed to inflate in a moderate to severe frontal, or near-frontal crash. The air bag will inflate only if the impact speed is above the system's designed "threshold level."

In any particular crash, no one can say whether an air bag should have inflated simply because of the damage to a vehicle or because of what the repair costs were. Inflation is determined by the angle of the impact and how quickly the vehicle slows down in frontal or near-frontal impacts.

The air bag system is designed to work properly under a wide range of conditions, including off-road usage. Observe safe driving speeds, especially on rough terrain. As always, wear your safety belt. See Off-Road Driving with Your Four-Wheel-Drive Vehicle for more tips on off-road driving.

Single Stage vs. Dual Stage Air Bags

Depending on the weight of your vehicle you will have either "Single Stage Air Bags" or "Dual Stage Air Bags". Vehicles that have a passenger sensing system also have dual stage air bags. If the rearview mirror in your vehicle has a passenger air bag status indicator printed on it, your vehicle has the passenger sensing system and therefore, it has dual stage air bags. If the rearview mirror in your vehicle does not have a passenger air bag status indicator printed on it, then your vehicle does not have the passenger sensing system and it has single stage air bags. See Passenger Airbag Status Indicatoror Passenger Sensing System.

Dual Stage Air Bags

If your vehicle has frontal air bags with dual stage deployment, the amount of restraint will adjust according to crash severity. For moderate frontal impacts, these air bags inflate at a level less than full deployment. For more severe frontal impacts, full deployment occurs. If the front of your vehicle goes straight into a wall that does not move or deform, the threshold level for the reduced deployment is about 10 to 16 mph (16 to 25 km/h), and the threshold level for a full deployment is about 20 to 25 mph (32 to 40 km/h). The threshold level can vary, however, with specific vehicle design, so that it can be somewhat above or below this range.

If your vehicle strikes something that will move or deform, such as a parked car, the threshold level will be higher. The air bag is not designed to inflate in rollovers, rear impacts, or in many side impacts because inflation would not help the occupant.

Seat Position Sensors

Vehicle's with dual stage air bags are also equipped with special sensors which enable the sensing system to monitor the position of both the driver and passenger front seats. The seat position sensor provides information which is used to determine if the air bags should deploy at a reduced level or at full deployment.

Single Stage Air Bags

If your vehicle has frontal air bags with single stage deployment and your vehicle goes straight into a wall that does not move or deform, the threshold level is about 13 to 16 mph (20 to 25 km/h). The threshold level can vary, however, with specific vehicle design, so that it can be somewhat above or below this range.

If your vehicle strikes something that will move or deform, such as a parked car, the threshold level will be higher. The air bag is not designed to inflate in rollovers, rear impacts, or in many side impacts because inflation would not help the occupant.