Seagate 7200.12 Stopped spinning after a few "fixes"

[Strider]

Hello and thanks for all the help you have already been. I have

been studying the posts and learned a ton but I have a few

questions before I go soldering my drives PCB.
I have a seagate 7200.12 model ST7350528as, I like this model

number, it fits seagate for totally screwing their customers and

not even getting it completely fixed in the next series.
The drive has the firmware bug. Yes, I did part of the procedure

for 7200.11 drives and then changed what other 7200.12 users

suggested.
I had to try a couple of times before it saved everything and

exited.
Problem is the drive won't spin up. I read another post where they

mentioned that since the board isn't fully connected to the drive

there is excess electricity flying around. I think with how many

times I tried to do this I shorted something or I pushed it to the

limit. I didn't drop any screws on the board or anything like

that.
Now, after finding tons of stuff on the net, I am trying to test

the tvs diodes.
I am uploading a picture of my board. It has two shock sensors.

Can you test those?

Here are my results from testing the tvs diodes, the ones with the

red arrow under them. I used two digital voltmeters and one analog

volt meter. I looked on the board but could not tell which side

was the anode or cathode. I will list the results as R(red) lead

to the left side and B(black) lead to the right side of the diode.

B R would be when I switch the leads.
Digital Meter (both digital meters had similar results)
TVS 1 (diode setting) TVS 2
R-B 448 R-B 709
B-R pops up to 1400 then B-R 1 (a few times
goes straight to 1. it would pop to
1800 then go to 1)

Annalog Meter (this is where I get confused bec it's backwards and

I don't know the scale. I did zero the meter.

I have pics drawn but can't duplicate them so I will just give the

numbers and describe the position. If I get this right 0 on this

meter is to the right and the numbers get bigger as it moves to the

left.

TVS 1 @ x10 TVS 2
R-B needle moved up a R-B nada, didn't move
little around 500
B-R moved to four B-R moved to 9

TVS 1 @ x1k TVS 2
R-B shoots up to 10 R-B goes to 10 then drops to
then goes to 20 100
B-R moves to 3 stays B-R goes to 6 and stays

Digial Meter @ 200ohms
TVS 1 TVS 2
R-B 462 pops up then 1 R-B 960 pops up then goes to 1
B-R Stays at 1 B-R moves to 6 and stays

Can someone tell me if either of these are bad? If not what else

can I check. Thanks in advance for your assistance.

Attachments

[hddguy]

The fix you made requires you to send spin down command to the HDD. Maybe you did this wrong and try to connect it to HDD 'live' and cause damage to it, maybe even other damage with it.

How many times exactly did you try these fixes (multiple variations of the fix also!) ?

We often get criticised for not condoning DIY repairs, and this is one reason why...

What commands did you run? Its also possible problem relates to some incorrect operations in Terminal - maybe you damage ROM chip via some terminal command as example.

Hopefully PCB is damaged, and ROM is good. But then you still have issue with the original problem you try to fix. Depending whats already been sent to the HDD this could still be a huge problem.

If the data is important then consult a professional. If not, get a replacment PCB and try it straight on it as non-native to check if it can start motor. If yes, then transfer ROM and try again. After this you will have better idea of problem it has now.

[BlackST]

Hope the ROM or the headstack has not beean toast-ed...

[Touchclarity]

I notice that in the lower picture you have circled 2 components in Yellow..... Can I ask you what you think these are?.....

[Alexii]

g sensors maybe

[Strider]

[quote="hddguy"]The fix you made requires you to send spin down command to the HDD. Maybe you did this wrong and try to connect it to HDD 'live' and cause damage to it, maybe even other damage with it.

Went thru my notes and pasted the commands i used in terminal. The only
exception is the m0,6,22.. which i did not issue.
Update with terminal commands that were used:
F3 T> m0,2,2,0,0,0,0,22
m0,6,22,,,,,22
re-plugged the drive's power cable (pull it out and back in) and when drive came back in Access Level T (prompt: F3 T>) I typed the final m0,2,2,0,0,0,0,22
m0,1,,,,2 ....
F3 T>/2
F3 2>Z DiagError
F3 2>U
F3 2>/
F3 T>m0,2,2,,,,,22
F3 T>/1
F3 1>N1V
F3 1>
Shorting read channels:
F3 T>
?
ctrl-C
U
i4,1,22
s444,0,22
h0
h1
T4
V4
V1
N1,, 22
When I first tied i was able to access terminal mode by blocking data channel.
After I issued commands in terminal I could only get into terminal by shorting
the read channels.

"We often get criticised for not condoning DIY repairs, and this is one reason why..."
I agree totally and was quite aware that I could lose everything but trying was much better
than tossing the drive.

[Strider]

I notice that in the lower picture you have circled 2 components in Yellow..... Can I ask you what you think these are?.....

At the beginning of my message I state that they are shock sensors and ask if there is a way to test them. Before you go knocking people at least read their message.

[Strider]

What is the initial problem of the drive ?
Was it spinning when you tryed to fix it with the terminal ? Or the drive was not spinning and that was the reason for you to try to fix it ?
If the drive was spinning do you remember what commands did you input on terminal ?
And did it stop spinning when you have done some specific action to it ?

Does your PC/PSU power up ok when you have the drive connected to the PC PSU ? If so then TVS are not shorted, as it will prevent the PC PSU from powering anything.

Can you try to insulate the head stack contact (but leave the spindle contact connecting the PCB) using some paper or plastic ? If Pre-Amp is shorted this might also prevent the drive from spinning .....

Initially the drive would not show up in the bios but it would spin up. I listed the commands i tried unfortunately, they are not in any order because i copied them from my 14 pages of notes i pasted from different messages and sites.
Thanks for that, yes the PC/PSU does power up. What is weird is that before i started this it would stop the pc at the bios but it would still have power.

Using a PS with just some fans hooked up and the drive resulted in no failure to get the fans spinning but the drive still did not spin. So is it safe to assume the TVS diodes are okay?

Just tried hooking up a board from another seagate and the drive does spin up but does a continuous clicking whereas with the orginal PCB it does not even spin up.

[Vulcan]

I notice that in the lower picture you have circled 2 components in Yellow..... Can I ask you what you think these are?.....

At the beginning of my message I state that they are shock sensors and ask if there is a way to test them. Before you go knocking people at least read their message.

Stop that attitude, if you want any further help. Nowhere did you previously state what you had circled in yellow (go and read your own first message, look for the word yellow, then come back and apologise to Touchclarity). Considering your initial jumbled text (e.g. I tried to figure out your TVS readings, which seem to be mixed between TVS1 and TVS2 in some way, and I couldn't do it and be sure I'd interpreted correctly) you are lucky that anyone is taking time to offer you advice. It's difficult to read your long story, so cut those people some slack who might have missed the odd detail, OK?

Based on the drive originally spinning and you having access via the serial terminal, the answer to your question is that your TVS were both OK at that point. I suspect that they still are OK (and could be tested, of course), but I can't see enough detail in your story to identify the point where the drive stopped spinning.

[BlackST]

I wonder if one of the 1 single letter ' magic commands ' was sent ...