If the airbag light is on in a vehicle, it is a very serious issue and should be resolved immediately. An illuminated airbag light means the airbag function is faulty and, in the event of a collision, the airbags in the vehicle will not deploy.
Once the vehicle is started, the computer system automatically checks all of the functions and lets the driver know if any are not working properly. If the airbag light is on, the cause could be one of several reasons.
The most common issue for the airbag light coming on in a car is a faulty sensor. Airbag sensors can wear out or get moved around over time and are no longer able to deploy an airbag when necessary. If the airbag was recently deployed, then the light will stay on until the airbag has been properly reset and is ready to be deployed again.
In the event that the airbag light does come on, the vehicle should be immediately taken to the nearest dealership or auto shop to be inspected. Once inspected, the mechanic can diagnose exactly what is causing the airbag light to be on and fix it so that the vehicle is safe to drive.