SRS airbags (supplemental restraint systems) are designed to provide a safety cushion for drivers and passengers in frontal collisions. They work in conjunction with seatbelts and deploy rapidly when triggered by a crash.
Sometimes, however, these devices can malfunction. It is important to promptly seek the help of a qualified professional if the SRS light stays on.
Seatbelts
The SRS (Supplemental Restraint System) is a safety feature in a vehicle that includes sensors, airbags, and a control unit. Its purpose is to provide safety to the driver and passengers in case of a severe accident. Upon detecting a collision, the sensors send a signal to the control unit, which decides whether the airbags should inflate and how. Each SRS airbag is inflated within fractions of a second and will cushion the impact, keeping the occupants safe from injury.
The airbags are usually symbolized by a symbol of an SRS car on the dashboard or steering wheel. If this light is on, the airbags are not working, and you should take your vehicle to a garage for diagnosis and repair. If you ignore this warning, you could be seriously injured in an accident.
When a vehicle crashes, the SRS computer checks for pre-tensioners to tighten seatbelts and sends a signal to deploy the front airbags. The airbags inflate with an electrical impulse, and the force of the impact is instantly absorbed. They remain inflated for a short time, enough to keep the occupants in their seats, but will deflate when no longer needed.
The SRS computer has a backup battery to ensure it retains data even when the power is cut to the airbag control module. If this backup battery has run out of charge, the airbag light will illuminate. It is possible to recharge or replace this battery, but this job should only be carried out by a qualified mechanic using specialized equipment.
Seatbelt pretensioners
Seatbelt pre-tensioners are a vital part of your vehicle’s safety system. They use an explosive charge to drive a concealed piston when sensors detect the signature abrupt deceleration of a crash. The piston rapidly drives the spool around which the fabric strap of a seatbelt is wrapped, tightening it instantly to remove excess slack and pull occupants firmly into their seats. This feature, called extra seatbelt tension, is applied moments before a collision to keep drivers and front-seat passengers in their seats. It helps them receive maximum protection from the car’s front airbags.
Some systems also preemptively tighten the belt during high-speed and robust decelerations, even if no accident is imminent. It can prevent occupants from sliding out of position during violent evasive maneuvers and reduce injuries from seatbelts that become twisted or trapped in the door frame or roof.
Using the FARS data, CATMOD analyses separately comparing cars with and without pre-tensioners, load limiters, and RF passengers with and without them produce similar regression coefficients (kh2 = 4.02). Although pretensioners and load limiters appear most beneficial in frontal impacts of cars, CUVs, and minivans, there is evidence that they may also improve belt effectiveness in side and rollover crashes.
Side Curtain Airbags
Side curtain airbags are inflated like curtains over the side windows and protect your head from striking the side of the car in a side impact crash. These are particularly useful when you collide with poles, trees, or tall vehicles such as SUVs. Side airbags have also been shown to reduce significantly the chances of severe injury and death in rollover crashes. They stay inflated longer in a rollover than a typical airbag and are equipped with sensors that sense when a vehicle is about to flip over.
They are very protective against partial ejection during a crash as well. A Harborview Injury Prevention and Research Center study found that passengers are 15 times more likely to be partially ejected in a side impact collision without side curtain airbags than those with them.
Unlike seat-mounted airbags, which are triggered by sensors in the outermost seat cushion and aim to protect your torso, side curtain airbags are activated from the roof lining just above the doors. When the sensors detect a collision, they are inflated in a fraction of a second, and they cover your side door and windows when deploying. It allows them to save lives in T-bone or side impact collisions with less of a crush zone than front impact airbags provide.
Knee Airbags
The knee airbag is a recent invention in car safety features. It deploys from the lower dashboard and is designed to spread impact forces across a driver’s legs in the event of a crash to reduce leg injuries. It is also meant to keep the knees and thighs from collapsing against the complicated dashboard in the event of a frontal collision, which could otherwise cause severe injury.
However, a study by the IIHS found that knee airbags aren’t very effective at reducing injuries in real-world crashes. The study examined data from over 400 frontal crash tests and real-world accident reports from 14 states. They found that knee airbags increased the risk of lower leg and right femur injuries, though head injury risks were reduced slightly.
Many automakers offer knee airbags to help their vehicles pass federally mandated safety tests that use unbelted crash test dummies. Therefore, knowing whether they would benefit people who don’t wear their seatbelts in real-world crashes is impossible.
Airbags can still injure and kill drivers and passengers even when fully functional. If a faulty airbag has injured you, you can file a lawsuit against the manufacturer to seek compensation.
