ANYONE else ever have this issue? Hope this is in the right forum area!
I have a jailbroken 3GS on 3.1.2 and its unlocked via ultra snow. I did a manual reset of the data right before I almost sold that phone. The phone freezes at the apple logo and when i do the hard reset and hold the home button and plug it in - it doesnt go to DFU mode, it goes to a dead battery as if it needs to be charged. I did let it charge but its a no go. If i cant get the phone to DFU mode, then im not sure how to fix this...PLEASE HELP!!
Sounds like a hardware malfunction.
All you can really do is leave it plugged in and hope for the best.
Or maybe take it in to an Apple store or repair shop.