SRS: Meaning, Why the Light Comes On, How it Can Protect You

You might have noticed a small label on your steering wheel or your passenger-side dashboard that reads “SRS air bag.” You can also find the same acronym in a warning indicator in your dashboard. What does SRS mean and why is it important?

What does SRS mean? 

SRS stands for supplemental restraint system, and it’s responsible for controlling your vehicle’s air bags and pretensioners. The system is computerized and is designed to work without any actions from the driver or passengers, which is why air bags are called passive safety devices. Several sensors spread around the vehicle detect information such as deceleration, braking, and impact location. It also detects whether a passenger is present in the front passenger seat.

The SRS is also known as supplemental inflatable restraints (SIR) and supplemental air restraints (SAR).

In the event of an accident, the system’s sensors will detect changes and send a message to the car’s air bag control unit. The air bag control unit will activate the air bags of seats that have passengers.

More specifically, the arming sensor and forward or discriminating sensor should be triggered at the same time to create a ground connection.

The arming sensor supplies electrical power to the air bag heating unit or squib inside the inflator module. The squib then converts the electrical power into heat energy, igniting the air bag’s propellant.

SRS Modifications

The conventional air bag has come a long way since it was first introduced as a safety feature in passenger vehicles. Over the years, automotive manufacturers have come up with their own formula to produce the safest SRS possible.

Dual-Stage Air Bag

A dual-stage air bag is one SRS modification that can be found in many vehicles today.

Dual-stage air bags have two separate inflators, with one intended for less severe crashes and the other for higher speed collisions. Also known as a smart air bag system, this type of SRS is capable of determining the severity of a crash.

A smart air bag system relies on three sensors一vehicle speed sensors, the seat belt fastened switch, and the passenger seat sensor.

Why Does the SRS Light Come On?

There are several different types of air bags in modern automobiles, and they all require finely calibrated sensors to work. The system is designed to reduce unnecessary deployment of the vehicle’s different air bags, but it also means it may need to be checked on a regular basis. If the SRS light on the dashboard activates, it indicates that there is a problem with the air bag system and it may not deploy in an accident. This may put you and your passengers at risk in case of a collision.

Here are the most common reasons why your SRS light might turn on:

• Defective air bag control module
• Crash or acceleration sensor problems
• Wiring issues

Is It Safe to Drive with My SRS Light On?

Generally, an illuminated SRS light won’t affect your vehicle’s drivability, so your car will technically run like any other day.

The real question, however, is whether or not you should continue driving with the SRS light on.

The light tells you that there’s an issue with the air bags or they might need to be serviced, so there’s always the possibility of them being unable to deploy in the event of a crash.

If you’re someone who doesn’t want to take the risk of driving without fully functioning air bags, then you shouldn’t take your car out until the issue has been resolved.

How Do Air Bags Protect You In an Accident?

Air bags are there to protect you in moderate to severe crashes. However, they can also deploy in low-speed crashes.

Trauma and damage to the head and brain are the most common causes of fatal injuries in a crash. Air bags are designed to reduce the chance of your head or upper body hitting the steering wheel or the dashboard in case of a crash. They are able to do this by quickly inflating and absorbing the force of the impact instead, preventing you and your passengers from hitting hard surfaces. They are also able to decelerate your body slowly.

During an impact, the air bag control unit first sends a signal to the air bag’s inflator unit. When the inflator receives this signal, the igniter starts a chemical reaction that quickly produces a harmless gas that inflates the air bag in less than 1/20th of a second. While the gas is harmless, the explosion can cause serious or sometimes fatal injuries if the passenger is too close to the air bag when it deploys. This is why it’s important to always maintain a proper driving position and why it’s important to still wear seat belts even in cars equipped with air bags. As their name suggests, air bags are there to supplement your seat belts.

Vehicle safety has come a long way. Before 1968, seatbelts weren’t even mandatory in vehicles. Now, there are a lot of safety features that are standard in most cars, and the SRS is just one of them. If the SRS light on your vehicle illuminates, make sure you have it checked to ensure that you’ll benefit from the protection it provides.