04 WRX STi. airbag light on... help?

So my airbag light turned on about a month ago.... it goes away some times.... but has been more consistantly on now.... in the last week it has not turned off once.

is there a sensor that commonly goes bad? has this happened to others? hoping for an easy fix.

Have someone or the dealer check the code, that is about the only way you are going to narrow down any sensors.