airbag light on

This past week i did a heater core on my 2001 cavalier. Since the whole dash had to come out, obviously i had to take the airbags out. Upon putting it back together before installing bothe airbags i turned the ignition to make sure i didn't have any problem so i would not have to take it back aloose. After getting everything back in the light has been on since. Is there a way to get the light off without going to the dealer? From what i read so far it may be a code or something isn't hooked up but i double and triple checked and everything is hooked up.