If your vehicle is showing airbag warning light stays on, here are the most likely causes and the parts you'll need to fix each one.
Moving the seat back and forth, vacuuming, or removing the seat can easily unplug or damage the delicate yellow airbag wiring harness underneath.
The seat belt buckle contains a micro-switch and a pretensioner mechanism that communicates with the airbag system. Dirt, debris, or internal failure will trigger the warning light.
A coiled ribbon cable behind the steering wheel (the clock spring) maintains the electrical connection to the driver's airbag. Years of turning the wheel can cause this cable to snap.
The weight sensor inside the passenger seat that detects if an adult or child is sitting there can fail, lose calibration, or be damaged by kneeling on the seat.
The airbag system is highly sensitive to voltage drops. A weak battery failing to provide enough power during engine cranking can trigger a persistent airbag fault code.
Crash sensors mounted behind the front bumper are exposed to road salt, water, and debris, which can eventually lead to internal corrosion and electrical failure.