Here's asite that will explain everything you need to know about airbag systems, airbaglights and resetting the system. Itshows you the location of the components and the procedure for diagnosingand/or resetting airbag light. Not allvehicles need everything replaced.
You cancheck to see if your car is listed here.
http://www.airbagsolutions.com/
Airbagsolutions.comalso has the fault code charts to tell you what is wrong and how to fix it!
Some vehiclemanufacturers let you access and reset systems without a scanner (like Toyota,Lexus, Nissan, Infinity, Honda, Acura, Ford, Lincoln, Mazda & Mercury) andsome require a scan tool.
Althoughit's a pay site ($14.95/day), it's a lot cheaper than going to the dealer
Here's the page in this site that tells you which cars needa scan tool and which ones can be done without
I hope I've helped you
http://www.airbagsolutions.com/scanlist.aspx
http://www.airbagsolutions.com/light.aspx
http://www.airbagsolutions.com/vehicles_list.aspx