I have a 2001 maxima with a blinking airbag light. The light blinks: 1 long flash, 2 short, 2 short 1 long, 2 short, 2 short. I am assuming the codes are 12, 21 and 22. How can I reset the srss system. Also, my car has a bad battery, could this cause the problems?

Here’s a site that will explain everything you need to know about airbag systems, airbag lights and resetting the system. It shows you the location of the components and the procedure for diagnosing and resetting airbag lights after a deployment. Not all vehicles need everything replaced.
You can check to see if your car is listed here.
http://www.airbagsolutions.com/

Airbagsolutions.com also has the fault code charts to tell you what is wrong and how to fix it!
Some vehicle manufacturers let you access and reset systems without a scanner (like Toyota, Lexus, Nissan, Infinity, Honda, Acura, Ford, Lincoln, Mazda & Mercury) and some require a scan tool.
Although it’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 need a scan tool and which ones can be done without
I hope I’ve helped you