Guys GUYS. I just brought back my Pokemon white from death. This is how i did it:
1. Cracked open the cartridge case. Do this super slowly, with your nails or a small flathead screwdriver.
2. The case should pop open, make sure it airs out.
(optional) I didn't need this, but clean the contacts of the motherboard. May help.
4. Once it's dry, assuming it was moist, pop it back in.
Bam, it should work.
I found out that it was just plain old moisture that screwed with it. You air and dry it it'll work! All is not lost!