Our practice > Air Bag System Components

An air bag system is a complex system of several components that can be found in various places throughout your car. To understand how these parts should be designed to work together as a safety system, it is important to first understand the function of the major parts that make up the air bag system. These major components include:

1. Air Bag Modules: these are the heart of the air bag system, and include the fabric air bag cushion (what some call the “pillow”), the inflator that generates the gas that fills the air bag, and the container that holds them. For front air bags, the driver’s air bag is in the center of the steering wheel, and the passenger’s air bag is in the dash in front of the passenger seat. Side air bags are generally located in the side of the seat or behind the plastic trim next to the seat. Newer rollover or canopy air bags are located in the edges of the roof. Some air bags were designed so that they deploy at speeds of more than 200 miles per hour! Thus, it is not surprising that they have caused serious injuries and even deaths to consumers who would not have suffered any serious injuries if the air bag did not deploy.

2. Air Bag Sensors and Diagnostics: the crash sensors are the “brains” of the air bag system; they decide whether to deploy the air bags in an accident or collision. They also decide when during the crash the air bags should deploy. In some cases, defects in the air bag crash sensors have caused the air bags to deploy in very minor fender benders where they were not needed, and some have even deployed while the car was simply being driven down the road.


The diagnostic portion of the air bag system is intended to diagnose certain electrical problems within the air bag circuits. These diagnostics evolved into modern “black boxes” that are named differently by different manufacturers: ECU (Electronic Control Unit), SDM (Sensing and Diagnostic Module), RCM (Restraints Control Module), EDR (Event Data Recorder), etc. Many of these black boxes record crash information (including seat belt use, crash severity, deployment timing, air bag electrical faults, etc.) and even pre-crash information such as vehicle speed, whether there was braking, engine RPM, and other information.

If you would like to read Taras Rudnitsky's article "My Air Bag Did Not Deploy - What Went Wrong", you can request it through the contact form on the right side of this page.


3. Clockspring: the clockspring is a special electrical component that is in the steering wheel and is only part of the driver’s frontal air bag system. This part allows electrical current to flow through the wires in the steering column to the driver air bag module mounted in the steering wheel, yet allows the steering wheel to freely rotate during normal driving without breaking those wires. Unfortunately, when this part is defective, it can prevent the driver’s air bag from deploying, even during a high-speed wreck where they are designed to deploy. Millions of these components have been recalled, often due to a poor design, lack of testing, or inadequate quality control.


4. Warning Lamps: the warning light in your instrument cluster or on your dash should show the electrical status of your air bag system. When you start your car, the warning lamp should flash or stay on for about six seconds while the diagnostic unit checks the system. If your warning lamp comes on while you’re driving, you probably have a defect in your air bag system. This can cause the air bag system to deploy for no reason while you’re driving. In some cases, it can also cause your air bag to not deploy when it should, even during a severe crash.


5. Passenger Air Bag On-Off Switches: In some vehicles, including pick up trucks and cars without a back seat, a key-operated on/off switch is located in the dash. These are typically intended to allow a driver to shut off the passenger air bag when infants or small children do not have an adequate back seat in which to sit and must instead sit in the front seat. We have seen some of these systems fail by allowing passenger air bag deployment even when the switch is set to “off”, or by preventing deployment even when the switch is set to “on”.


6. Passenger Presence Detection and Occupant Classification Systems: Newer advanced air bags include various methods to determine the presence and size of the front passenger, in order to adjust how forcefully the air bag should deploy. If there is no passenger, or if an infant or child becomes too close to the dash, these advanced air bags are typically intended to prevent the deployment of the air bag. If the occupant is an adult, such systems can tailor the inflation force to the person’s size or position. A failure in these systems can have deadly consequences.


7. Other Components: Other parts of your car should also be designed to work together with your air bag system during a crash. Examples of these parts include: deployment doors, trim covers, knee bolsters, steering columns, steering wheels, sun visors, windshields, seats, dash or instrument panels (I/P), and sometimes even the inside rear view mirrors. Depending on your specific vehicle, other components can also be part of your car’s air bag system.

 

In choosing a law firm to represent you in an air bag defect case, it is important that the attorney has a solid engineering background with experience in analyzing air bag system performance. Taras Rudnitsky, who was an air bag engineer for General Motors and a court-recognized expert, now represents consumers as an attorney in car defect cases.  He has nearly 20 years of experience in analyzing the performance of air bag systems. If you have any questions about whether your air bag system performed properly or contains a defect, please do not hesitate to contact us; there is never a charge for an initial consultation.