How do you fix the onboard backlight mechanism?

I have an apple 2nd generation that clearly has an issue with the backlight mechanism on the logic board. I swapped out the original LCD with 2 new ones with the same issue of having no backlight. Anyone have any luck resolving this type of issue? Does it reside in the port itself perhaps?

This iPod had a little bit of water damage with a little corrosion, but everything works fine except for the backlight. I used some rubbing alcohol isotropic to clean up the corrosion, but still no luck.