So if your phone won't turn on, access download or recovery modes you have 3 options. 1) send the phone for warranty repairs if it is still under warranty. 2) Try the information in the link I gave you a couple posts up or 3) You need to get the phone Jtag'ed. There is a place 75 miles from my house that will Jtag a phone in 1 business day for $50 if you bring it to them or 2-4 if you mail it to them.
Good luck and let us know what you do to fix it or if you get it fixed.
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