Fact vs. Fiction
Is what you know about airbags true?
Time and time again we come across individuals or shops who have heard something about an airbag or repairing an airbag that is just not exactly right. They read something somewhere, or were told this about that, by someone; most of the time it's only half right. Over time, these are the things that create urban legends and myths, but more importantly can cause improper repairs or unnecessary expense. Having the correct information is critical to both repairing these systems properly and success in your business.
The following brief answers will help to correct many of the misconceptions surrounding these important safety systems.
I need to wear my seat belt in order for the airbag to work.
False.
Although many 
vehicles combine the seat belt pretensioner deployment with an airbag deployment, the use of the seat belt does not determine whether the airbag will deploy or not. Airbag deployment is determined by a series of sensors in the vehicle that measure deceleration, and impact data during a crash. Airbags are a "supplemental restraint". Airbags are meant to assist the seat belt in protecting the occupants of a vehicle, but will operate independent of them. Every carmaker strongly recommends that seat belts be worn at all times, as they are the primary defense against personal injury during a crash. Many states now require the use of seatbelts..."It's the law!"
The "5 STAR Rating" on my car means I'm safe.
Partially True.
It only means you're 'safer' on a relative scale. The US government has set up a standard of guidelines to measure the effectiveness of safety systems. The Insurance Institute for Highway Safety conducts independent tests on many vehicles produced and rates these vehicles according to these government guidelines. For frontal crash ratings, vehicles are crashed into a fixed barrier at 35 miles per hour. Here are the details of what these stars actually mean:
1 Star = 46% or greater chance of serious injury
2 Stars = 36% to 45% chance of serious injury
3 Stars = 21% to 36% chance of serious injury
4 Stars = 11% to 20% chance of serious injury
5 Stars = 10% or less chance of serious injury
Cars today are required to have side airbags, curtain airbags or both.
False.
Each vehicle manufa
cturer offers side impact protection according to the design of that vehicle; some as standard equipment and some as options. With all of the recent news about rental car fleet vehicles being sold without side airbags, many people are questioning the integrity and honesty of both the carmakers and the companies selling these cars. As of 2009, side airbags were not required on any vehicle although a high percentage of the vehicles produced that year did have them as standard equipment. It is (and was) legal to sell a vehicle without a side airbag as long as it is represented as such.
Hitting the the body or frame of the car with a hammer will cause the airbag to deploy.
Partially True!
Although certain crash criteria must be met in order for a deployment to occur, there have been instances where simply working on the car has caused the airbag to deploy. The most common accidental deployment is a side impact activating the side airbag. These sensors, mounted near the center pillar or floor edge, are much more sensitive and may cause an accidental deployment by striking the area near them with a hammer or in some cases even slamming the door too hard. There are also records of Emergency Responders accidentally deploying an airbag with the 'Jaws of Life' or by inadvertently cutting through a roof curtain airbag canister. ALWAYS disconnect and power down the system before doing any heavy work on the vehicle.
The airbags will work even if the little airbag light is on.
False.
Every vehicle has an airbag control unit that constantly monitors the airbag system as long as the key is on. Initially, when starting the car, the airbag light should illuminate or flash for approximately 6 seconds and then go off. If an airbag system has a fault or is inoperative, the indicator light will
- never illuminate
- will remain illuminated
- flash continuously.
In those cases, there is a fault in the system and the airbags will NOT DEPLOY.
The smoke in the car after an airbag goes off is toxic or dangerous.
False.
The smoke seen after an airbag deploys is a combination of both the exhausted nitrogen gas (harmless) from the explosion and the powder used to keep the bag lubricated and free from sticking to itself. Although there have been isolated cases of the airbag actually catching fire from the heat of the explosion, the most common complaint is of mild respiratory distress from breathing the combination of the corn starch based powder and exhausted gases. The best advice is to exit the vehicle as quickly as possible following a deployment.
The "BLACK BOX" in my car has all the crash data, like an airplane.
Partially True.
All vehicles with an airbag have a so called 'black box'. This refers to the airbag control unit and none of them are actually black. These control units are called many things; SDM (Sensing & Diagnostic Module), RCM (Restraints Control Module), Diagnostic Monitor, SRSCM (Supplemental Restraint System Control Unit), and ORC (Occupant Restraint Controller) among other things. Currently, all control units constantly measure speed, impact, deceleration, system readiness and other vehicle functions, but only about 60% of the car makers implement "Event Data Recorders" (EDR) into these units and store this data following a crash. As of the date of this article, the only vehicles that store event and non-event crash data are:
Chrysler, including Dodge, Jeep, Chrysler, Mitsubishi and Sterling
Ford, including Ford, Lincoln and Mercury
GM, including Buick, Cadillac, Chevrolet, GMC, Hummer, and Pontiac
Isuzu, Jaguar, Mercedes, Saab, Saturn, Suzuki and Toyota
Generally speaking, crash data retrieval on these vehicles is available from model year 1997 to present day with some coverage going back to 1994. According to our research, car manufacturers will be required to include EDR on all vehicles produced after September 1, 2012.
Unplugging the battery will clear the light & codes.
False
When airbags first became mandatory (about 
1992), most vehicles had a control unit that was less advanced than those seen on cars today. There were actually some models that did support that method, but since about the mid 90's, this is not the case. There is no vehicle produced today that will reset the light by disconnecting the battery. Currently there are three methods, depending upon the design, to accomplish resetting the light:
1. The system will reset itself once the fault is corrected
2. The system requires a new control unit be replaced and comes reset
3. The system requires a scan tool to access, configure, program or reset the light
One scanner will work for all cars.
False
There are currently about 30-40 car manufacturers producing vehicles for the US. Some of these cars use the same software and can be read by the same scan tool, but for the most part that statement is not true. With the changes every year in airbag systems, and the methods for resetting and reading these vehicles, there is no single scan tool that will read all of them. In addition, those that do read multiple vehicle lines require upgrades each year.
Every car has front sensors behind the bumper.
False
Once again, when airbags were first introduced to the US, most vehicles had multiple remote sensors located in the front of the vehicle. That has all changed over the years. Some manufacturers do not use front sensors at all. Some use them but mount them on the frame rail while others mount them in multiple places on the radiator core support. Others mount them under or behind the lower frame cross member. The use and location of front sensors is not uniform and is determined by each manufacturer.
When the airbag light is on, the clockspring is bad.
False.
When the light is on, the system needs to be diagnosed to determine the exact cause of the problem. Although the clockspring is a common component that fails, it is not always the cause of an airbag light illumination. Any component deployment, wiring malfunction, poor connection or damaged part can cause the light to illuminate. With the implementation of seat weight sensing systems, even a mis-calibration of that seat sensor will cause the light to come on.
Having the correct information is critical in today's world.