Climate control fuse blows

[dizzan]

Hey all, been having a problem with my 92 LS-l lately that the 30amp fuse for the climate control (and whatever else may be on it) keeps blowing.
When I got the car the heat/etc did not work. I replaced the fuse and it worked for several days with no problem, then blew again. After that, I replaced it again and looked around for any bad grounds and couldn't find anything obvious. It worked again for a few days, then I remember hitting a hard bump and the heat went off and the fuse blew again. Since then, it blows as soon as I turn the ignition with a new fuse in..
Anyone have any idea on where to start troubleshooting where the problem may be? Thanks!