seagate 7200.12 does not respond on terminal commands

[SMax77]

Hi, all.

 

I've faced a problem with my 7200.12, looks like a "0 LBA" shown here. After power up it sounds "t-r-r-r-r" 4-5 times and stops.

 

But the main problem is that I can not receive any answer from hdd to terminal 0x1A command (hex Ctrl+z command, isn't it? I'm using very simple "Terminal" with hexadecimal transmitted codes).

 

RS232 - TTL adapter connected correctly (sure by a huge number of forums and oscilloscope - I'm electronic engineer).

 

My hdd do not respond me in any condition of PCB and the brick:

Fully connected - failed,

Motor disconnected (by isolator) - failed,

heads disconnected (by isolator) - failed.

 

hdd "no reply" state is confirmed with oscilloscope (no changes on sygnal).

 

port settings : 38400, 8 data, 1 stop, no parity, no handshaking.

hdd: SN: 6VPEDKLG

        model:ST31000524AS

        firmware: JC4B

        PCB 100574451 rev.B

 

Could anybody help me? May be I need to short something? disconnect something? Send other command?

 

Thanks a lot in advance.

 

 

[jaclaz]

There are some models that possibly need to have the "Read Channel" shorted, see:

http://www.msfn.org/board/topic/172245-720012-terminal-unlock/

 

But the issue here is that even once you will have access to terminal you won't know which exact commands to issue or how to diagnose the exact problem, the:

"t-r-r-r-r" 4-5 times and stops

 

is likely to be something that you cannot simply recover via terminal commands.

 

jaclaz