Have you fixed your problem? I have the same issue and I do not know how to fix the ribbon cable.

I have the same problem. Flex cable can be bought from aliexpress.com http://www.aliexpress.com/item/for-New-iPad-iPad-3-3rd-Gen-Brand-New-A-Quality-Mainboard-Interconnector-Flex-Cable-Repair/2053470123.html But I do not know how to remove old one and replace with new. Someone has an idea how to replace it?