Default GNex (toroplus Sprint) wont enter fastboot.

hey guys,

I bought a sprint galaxy nexus off of a guy on craigslist for a pretty good deal, the only downside was that it had the PC---/!\---plug symbol when it boot up. well after a couple hours of tinkering i have bypassed that and can now get into "odin" mode or download mode, but i can't enter fastboot. When i try, i just feel a vibration like its trying to start up, but the screen stays black. I have tried flashing back a stock image with odin, but every time it stops at flashing CDMA radio. Any and all help is appreciated in the matter.