Failure Code

Hi,

I have a 2000 Neon. My engine light is on in the dash board. I assume I only forgot to close the gas lid correctly. I tightened it, but the light is still on. I think I have to erase the code first. Does anybody now how to a: read-out the failure code b: what the code means and c: how to erase it ??

Thanks for your help.

Have a good one