What do you mean with Help needed?
If you know that your Corrupted SD card is the problem... what can we do for you then?
On a second read... is your SD card corrupted? Or your Wii's System Files are corrupted?
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inb4: Be sure that you have a NAND backup and a way to access BootMii. Restore your NAND using BootMii and the problem should be solved.
If you don't own a NAND backup, you can download the entire Wii OS from the Internet and install it.
If you don't have a way to access BootMii... then there's not much you can do about it.