Thank you for asking your question on JustAnswer.
The air bag light comes on the the SRS system sees a system fault. You can clear the code by removing the positive battery cable. That being said, if you do not repair the reason for the light coming on then the light will return.
How can I check what fault it is, I have a snap-on MT2500 scanner, can I check it with that?
Enclosed is the method for retriving the code.
The code 13 is an issue with your forward crash sensor.
Here is the test as well as the wiring diagram.
Got it I'll check it out, thank you.