2000 A4 Avant Airbag Light
 

So back in September, when moving into my universities dorms, I went too far over one of those "mobile" curbs, the ones that are there to let you know when you can stop, well it sorta f**ked up my bumper. I was able to bend back the plastic on the bumper so that's fixed. However, my airbag light has been ever since then. Where should I begin to look for fixing this??
Thanks