I have a similar problem with my s3 but when I put it into download mode it wont stay on long enough for odin to reset it to stock
<ID:0/003> Added!!
<ID:0/003> Odin v.3 engine (ID:3)..
<ID:0/003> File analysis..
<ID:0/003> SetupConnection..
<ID:0/003> Initialzation..
<ID:0/003> Get PIT for...
I finally upgraded to sprint gs3 from epic 4g that was running cm10 4.1.2
and now I'm stuck on stock tw 4.1.1 is jelly 4.2 coming soon? Sorry for being a complainer haha