My late 2009 unibody MBP won't boot. I have already booted in single user mode, ran fsck -fy until I get no errors. But when typing 'exit' or rebooting in verbose mode I see, after fsck runs:
Failed to issue COM RESET successfully after 3 attempts. Failing... disk0s2: no such device disk0s2: media is not present.
The HD appears to be working, because when booting in single user mode I can run fsck successfully and can browse the HD, listing directories, inspecting files.
I just don't know why the OS can read the disk but reports it as 'not present' when booting.