Need some ideas here. Got a 2004 Duramax with the LB7. Flashed it with EFI Live Saturday night and after flashing, truck didn't start. Pulled out ECM and bench flash stock tune back in then flashed other tunes back in and still won't start by the ignition. All I keep pulling for codes is u1000 and there's 4 of them. I can jump the starter and runs just fine and everything works. Any ideas? Thanks