Honda - OBD-II reader scan tool that can also diagnose air bag light - Motor Vehicle Maintenance and Repair Beta

Interestingly, you can read the code without a scanner. The airbag light or ABS light (and even the check engine light) will all blink the codes when the OBD-II connector is properly bridged. For example if it blinks 5 time slow and 1 time fast you have a 51 code. All you'll need is a paper clip.
This video below will demonstrate how to do it. I just did this and it works great. Once you obtain the code you can go online and look up what it means.

I have a 2005 Honda Element and I was actually able to just reset the light because the sensor misfired. This video will show you how to reset the light:

Vehix411 is a great website for do it yourself videos!! You"ll be surprised how easy it is.