Back to GuidesSRS stands for Supplemental Restraint Systems, or airbags and the systems related to them in your vehicle.
Starting in 1998 all cars and light-duty trucks sold in the United States have been required to have driver’s side and passenger’s SRS.
This is an abbreviation you may have seen on your dashboard's display, either turning off shortly after startup or illuminated consistently while the car is running.
SRS isn't just the airbags themselves but also the components which allow the airbags to deploy properly.
Importantly, the SRS light may be the letters SRS, the word Airbag, or an illustration of a seated passenger with a deployed airbag in front of them. In modern vehicles with digital screens rather than traditional gauges and warning lights, a more informative display may appear with specific instructions or warnings.
Is Your SRS Light On? Here is What You Should Do.
If the SRS light on your dashboard is illuminated it is likely your airbags may not function properly, or at all, in the event of a crash. So, it is critical to get your car checked out right away. A trusted automotive mechanic, car dealership, or even some car parts store may be able to diagnose the issue for you.
A vehicle’s SRS system relies upon a variety of sensors, an airbag control unit, and other components to make sure there is proper airbag deployment and that the airbags work in concert with other safety systems in the vehicle like the seat belts.
Though the SRS light will not prevent your car from operating normally, it does mean that the safety of you and your passengers will be compromised in the event of a crash.
Do not continue to drive unnecessarily if you have an SRS warning on your dashboard, get it checked out as soon as possible, and drive with extra caution as you proceed to the repair shop or dealership. Ideally, towing the vehicle to a repair shop would prevent the chance of unnecessary injury, and is the best option, though it can be expensive.
What Can Cause an SRS Warning Light?
There are a variety of reasons that the SRS light will come on:
A prior accident that did not cause the airbag to inflate can mean that the SRS system needs to be reset.
A damaged or corroded sensor could also be the culprit.
The SRS system has a backup battery, and if the battery loses its charge, this can cause the light to illuminate.
Another common reason could be that the connector or plug that attaches to part of the system may be disconnected or unplugged.
An issue with the seatbelt latch or pretensioner may cause the fault.
A sensor that determines whether the passenger seat is occupied can also cause this warning.
The airbag clock spring may have simply worn out. The clock spring is a coil that maintains the connection of electrical equipment on the steering wheel, including the airbag, horn, and any buttons or controls, and is a common reason for SRS faults in older cars.
Finally, the SRS computer itself may have an error or need to be replaced.
How Much Will a Repair Cost?
The average cost of replacing an airbag crash sensor is around $400.
The repair cost for an SRS light can vary greatly depending on the cause of the error code. More complicated SRS systems will make diagnosing some issues take longer and be more costly as well.
If the issue is with the seatbelt or tensioner the cost may be around $80 to $100.
The airbag itself costs between $150 to $800.
The cost of fixing a bad or unplugged connection will depend on the time it takes to diagnose and reconnect.
Resetting the SRS control module should cost between $50-$120.
If the SRS computer needs to be replaced that can cost between $400 and $1200.
A clock spring replacement can run between $200 and $750. Remember vehicle parts costs vary greatly depending on the year, make, and model of the vehicle.
A new luxury vehicle with a complicated multi-airbag system will cost more to repair than an older vehicle with fewer sensors and components. If you are concerned about the cost, obtain an estimate for the repair and call other local shops for a second opinion or quote for the repairs.
Even though it may be costly, it is important to have the SRS warning light diagnosed and repaired by a professional before continuing to drive your vehicle.
Neglecting to make the repair may result in unnecessary injury and vastly more expensive hospital bills, or even death in the event of an accident.
History of SRS Systems
Airbags are part of a group of safety systems classified as passive safety restraints because they do not require any action on the part of the vehicle occupant to work. They are meant to supplement active restraints like seatbelts.
The first airbag design was patented in 1919 and two designs for airbags intended specifically for automotive use were patented in the early 1950s in Germany and the United States. These designs used compressed air to inflate the bag, however that technology did not inflate the bags fast enough to thoroughly protect occupants.
Later systems used chemical reactions with sodium azide or strontium nitrate, or an electrically triggered explosion to inflate the bags more rapidly. Airbags must inflate fully in fractions of a second to protect the driver from impacting the steering wheel or other parts of the interior of the car.
GM and Ford began offering airbags as optional equipment in the early 1970s, marketing the device as an alternative to seatbelts. The first car to have something like a modern SRS system was the 1981 Mercedes-Benz S-Class.
Remember SRS stands for supplemental restraint system, and the Mercedes design was meant to work in conjunction with the seatbelt pretensioners to protect occupants in an accident. The first car to have both driver and passenger airbags as standard safety equipment was the 1987 Porsche 944 Turbo.
In 1991 a law was passed that would require all cars and light trucks built after September 1st, 1998 to be equipped with driver and passenger airbags. One year after the requirement went into effect, the National Highway Traffic Safety Administration estimated that airbags had saved over 4600 lives.
Interestingly, for a short time, another SRS feature was included in some cars. A motorized shoulder harness that automatically moved into position as the car was started. These proved to be unreliable to operate, annoying to live with, and dangerous when not used with the lap belt, which required the effort of the seat’s occupant to buckle. The automatic seatbelt proved to be a lame attempt at passive safety.
Today many cars are equipped with side-curtain airbags and side-torso airbags to protect from side-impact collisions. Airbag innovation continues with rear passenger front-collision airbags, seatbelt airbags, and even knee airbags.
Depending on the specs of your car there may be as many as ten or more airbags as part of the SRS, so it is very important to be sure that all of the switches, sensors and other components of the car’s airbag system are in proper working order.
Now that you know the meaning of SRS, if you have been driving around with an SRS warning light get your car in for a check-up right away, it could save you or your passengers’ lives.
