ST3000DM001 Grenada comes ready then goes bsy

[Tri5]

I have a ST3000DM001 - 1CH166 Grenada that spins up normally and will come ready, will allow some momentary access to the user area, then go bsy and require a repower. If you try to do anything else like ID the drive it will also go bsy. The terminal output on startup shows no error messages at all.

Patching the ROM and using tech unlock I can get access to the terminal, I've turned off most things in the HDD ID but left on Media Cache and Media Scratch Pad Control, and turned on Disable Look Ahead. Pretty much all the sys files will read all good bar a few, but when I try to rewrite those ones it just goes bsy again.

I am relatively new to PC3k, I've read the manual cover to cover but I can't work out what more to do here, if anyone could help would be much appreciated.