How to Check Airbags
When the ignition switch is turned on, the airbag malfunction indicator light (SRS light) on the dashboard should illuminate and then turn off after approximately 5-10 seconds, indicating that the system is working properly. The illumination time may vary slightly depending on the vehicle model. If the SRS light remains on, it indicates a malfunction in the SRS system, and the system should be checked.
General checking methods are as follows:
- The SRS light should illuminate normally when the ignition switch is turned on. If the light does not illuminate, check if the SRS light bulb is burnt out or if the wiring is open.
First, disconnect the airbag wiring connector and short-circuit the terminals of the airbag-side wiring connector.
Use a multimeter to check if the collision sensor wiring is open or short-circuited.
Use a multimeter to check if the DC impedance of the collision sensor meets the vehicle model’s technical requirements; otherwise, replace the collision sensor.
Check the installation of the collision sensor. If it is loose, tighten it.
Check the connection status of the SRS system wiring harness and connectors. If any abnormalities are found, repair or replace them.
Clear the fault codes, then repeatedly turn the ignition switch on and off to check the fault codes. If normal codes are output, perform further electrical checks. If fault codes are output, determine additional work items based on the fault codes.
How to Troubleshoot Airbag Faults
- If the airbag indicator light illuminates immediately after starting the car, this is normal. If the light remains on, it indicates a fault.
False airbag fault: Airbags are controlled by wiring. If the battery is severely depleted, the airbag will send a low voltage signal, generating a fault code. This situation does not require repair; clearing the code is sufficient.
Faulty airbag itself: Excluding the above causes, the airbag itself is most likely faulty. A car’s airbag typically consists of a processor, sensors, electronic control unit, airbag, and airbag module. An illuminated airbag indicator light suggests a fault in one or more of these components. As you can see, airbag faults are complex and require an OBD2 airbag scanner to read the fault codes to locate and resolve the problem. It is recommended to have your car repaired at a repair shop as soon as possible.
How to Check if Airbags Have Deployed
Inspect the vehicle’s airbag assembly. A non-deployed airbag is very clean. A deployed airbag is usually covered in dust, oil, and may even show signs of damage. The screws securing the airbag may also be loose.
Smell it. A deployed airbag will emit a pungent gunpowder smell; you can smell it to determine if it has deployed.
Check the airbag locking mechanism. Normally, pulling the airbag will not completely lock it. If it does lock, the airbag has likely deployed.
Use diagnostic equipment. While the above methods are intuitive and simple, they are not very accurate. The most reliable method is to test the airbags using professional equipment. For example, an OBD2 diagnostic tool can read the vehicle’s collision data and airbag system records, thus showing whether the airbags have deployed. The data and force of deployed and non-deployed airbags will clearly show the difference between them. Using professional equipment such as a car scanner to determine if a car’s airbags have deployed is the most convincing method.