I suspect a poor ground but first thing is to have the car scanned for codes (service engine soon light).
Check the intsrument panel connections, look for corrosion and wire condition.
The air bag system maybe a seperate issue and needs to be diagnosed in a different way. First resolve the ipc issue then look at the airbag system.
You can have the car scanned at auto zone if your in the States.
Which brings a point, please add your location to your sig as well your cars year and trim level, also any mods etc as it makes it easier for us to help you