A modern car consists of many complex systems. The passive safety system SRS Airbag is almost the most important in the car, because the health and life of people depends on the quality of its work in an emergency. If it fails, the corresponding light on the dashboard lights up. This light bulb usually causes panic among drivers, because it indicates that the airbags may not work in the event of an accident. Today we will take a closer look at the SRS system, find out what to do if the airbag bulb lights up, and consider a few specific examples from the life of car owners.
SRS system
All modern cars in the cabin can be found marking SRS. What does it mean? This abbreviation stands for Supplementary Restrain System, which in Russian means "Advanced Security System". Often added to it the phrase Air bag, which translates as "airbag". Pillows are the main attribute of the system. But besides them, SRS also includes:
- Seat belts.
- Tensioning devices.
- Shock sensors.
- Pyro cartridge.
- Electronic control system.
Like any other automotive unit, a security system can fail if one small part breaks down or a reliable relationship between elements is lost.
Principle of operation
When the sensor detects a shock, it transmits an alarm to the system and the pillows open. From the moment of impact to the opening of the pillows, 30-35 milliseconds pass. In modern cars, there are special batteries that put the system into operation even when the main battery is damaged.
Why does the Airbag indicator light?
If the airbag light on the dashboard of your car lights up, then there is a problem in the system. The indicator can light constantly or blink at a certain frequency, informing the driver of the error code.
If everything is good in the security system, then when the ignition is turned on, the light flashes about six times. Thus, the system makes the driver understand that everything is in order with her. After that, the indicator goes out on its own and reminds itself only at the next start of the motor. But if any problems or errors are detected, the lamp continues to light. As soon as the electronics noticed an error, it automatically starts searching for the cause and transmits the fault code to the memory.
After a certain period of time after the first test, the system checks all the elements again. If the identification of the breakdown was erroneous or the signs indicating the malfunction disappeared, the diagnostic module erases the error code sent to the memory earlier. In this case, the lamp goes out and the machine continues to operate as usual. When the system re-recognizes the malfunction, the light continues to flash.
Common Malfunctions
As you already understood, if an airbag lamp lights up in your car, then a malfunction in the system is always present. Modern car manufacturers approach the security management system with particular responsibility. Therefore, the devices involved in this unit are considered the most reliable and trouble-free in the whole car. So if the airbag malfunction lamp comes on, there is no point in complaining about the unreliability of the system itself. Remember that the diagnostic organs of the SRS Airbag are very rarely mistaken!
If the Airbag indicator is on in your car, this may be due to the following problems:
- Violation of the integrity of one of the elements of the system. It does not matter whether it is small or large, important or not.
- Violation of the signal between the elements of the system.
- Problems with contacts located in the doors. Most often this happens after repair or replacement of contacts. If you forget to connect one of the connectors, the lamp will light up.
- Damage to shock sensors.
- Short circuit or any kind of damage to the wiring in the system circuit.
- Blown fuse. A simple problem that many people remember last, having already disassembled half the car.
- Software or mechanical damage to the SRS Airbag control unit.
- Violation of the integrity and consistency of circuit elements due to replacement or repair of an alarm.
- Inaccuracy when replacing seats or cleaning the cabin. Under the seats is the wiring, which can damage the entire chain of devices.
- Restoring pillows after an accident, without resetting the memory in the control unit.
- High resistance on one of the pillows.
- The voltage on the vehicle is too low. If the airbag bulb lights up for this reason, when replacing the battery, everything will fall into place.
- Exceeding the life of the squibs or pillows themselves. As a rule, this period is about 10 years.
- Unprofessional tuning, which often leads to a violation of the integrity of the electrical circuit or sensors.
- Wet sensors when washing the machine.
- Incorrect battery replacement.
- Inaccurate steering wheel replacement.
Troubleshooting
Now we know why the airbag bulb lights up. It remains only to find out how to solve this problem. Troubleshooting consists of the following steps:
- To begin with, the system itself checks its performance during ignition on. If errors are detected, she writes their code to the central control unit.
- The wizard reads the code and determines the cause of the problem.
- Special diagnostic equipment checks the system.
- The master performs repair operations.
- It remains only to update the memory of the control unit, and the problem is solved.
Trying at home to repair an SRS Airbag system is highly discouraged! Firstly, it’s not easy to get to the elements of the system. Secondly, to eliminate the breakdown, it needs to be identified. And without special equipment this is impossible. Thirdly, this system can save your life, therefore it is better to entrust its repair to professionals. Riding ignoring the indicator is also dangerous. If an accident occurs, the pillows may not open. But they can easily hit you for no reason.
Now let's look at several examples of solving this issue by drivers of different brands of cars.
The airbag light on the Chevrolet Lacetti caught fire
Once the driver of this car noticed that during engine start the SRS lamp does not blink, but burns for five seconds, then goes off. This was repeated every time the engine was started. The reason was as follows - when removing the chair, the driver disconnected the pillow and turned on the ignition to gain access to the cigarette lighter. The system considered an error, and the airbag lamp on the Lacetti lit from this. Then, when the chair and contacts were returned to their place, the car continued to remind about the problem.
"Renault Logan"
The owner of this car had a more significant problem. It all started with the fact that once the SRS indicator lights up. Since the driver had some experience in this matter, he decided to figure it out on his own. Having removed the front driver’s pillow, the man disconnected the wires from it (having previously disconnected the “mass”), removed the steering wheel and the plastic cover. By the way, he had to remove the steering wheel with a friend, as he is tightly pressed. This happens not only on Renault Logan vehicles. The airbag bulb turned on, as it turned out, after removing the cover, due to the fact that the ribbon cable was torn off, and on both sides. Having removed the steering column switch block, the man took out a damaged element and replaced it.
Nissan Nout
After cleaning the car, the owner noticed that the SRS indicator is on. Apparently, the reason was that the man vacuumed the compound located under the seat. At first, he tried just removing the battery terminal. On some cars, this helps if the airbag light comes on. Nissan is designed so that error information is immediately stored. Fortunately, this is not the only feature of Nissan cars. It turns out that in cars of this brand, to clean the system from errors, you need to perform the following sequence of actions:
- Depress the brake pedal. She should not be let go until the end of the procedure.
- Turn the key to "ON" mode.
- Wait until the SRS indicator flashes.
- Quickly turn the key to the "OFF" position.
- Items two through four need to be repeated 3-5 times.
If it does not help, then there is a more serious problem, and you need to contact the masters.
Toyota Camry
At one motorist the airbag lamp on the Camry-40 lit up for a very interesting reason. As already mentioned, not only airbags, but also belts are connected to the security system. So, once in an emergency, the owner of a Toyota Camry, as they say, “fired a belt”. Shot - it means he was pulled back at such a speed that the stopper worked, and the belt jammed. The pillows did not open, but the situation was recognized by the system as emergency and remained in the control unit, as a result of which the light came on.
