Hello and welcome to Just answer.com, Super mechanic here. About your vehicle.
There are several areas of the air bag system that may give you a problem. However, when there is a problem, the controler should set a trouble code. You will want to have the SRS system scanned to see what code(s) may be present. You will need to have it scanned at a shop that has the proper diagnostic tools, or at the dealer. Let me know what code(s) they find and we will have a better idea of what may be causing the light to stay on too long.Or stay on.