Psu burned and some electric discharge was visible when I was switching off my pc. Enough voltage went on mb (that was also not recoverable after it - even without beep), as seconds before discharge I heared some strange sound on my sound outlets. When I also checked hd in service it is not defined, as well as spindel is not spinning. So I ask what can I do - can I change just hd pcb bf41-00091b by the same workable board? Should it be enough - or should I also resolder old bios (flash) chip if possible? Can you provide the schema for bf41-00091b board? Do it have tvs diodes to change just them, despite it seems nothing have been burned and desoldered on the pcb visually? I will be grateful for the help. The hd and whole pc have about decade and it never worked badly.

Can you provide a photo of the PCB?

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A backup a day keeps DR away.

I can not know if my pc is turned on - as my mobo is totally silent as well. Despite the coolers of processor and pc corpus is spinning when I turn on pc. Non defined hd was revealed in service and nothing more. Non rotating spindel - by my known local pc master. It would be fine to have the boad bf41-00091b schema to know exact elements on board. For example tvs: so maybe the photo would allow to show me by yours where (if it is ) is such diodes? Maybe tomorrow I would be able to produce if i would not pass to repair. No more info you would not get from such pic. For example there is - pararel NOR flash M29F chip - does it contain the firmware version? How could I know it if hdd is not switching on? Is FW irrelevant of pcb bf41., just unique and linked to platter? (i have seen such tk100-300 on the net concerning the sp0812n -is it the same). I also read that non-spinning could be the result of destroyed vcm controller that is probably the ha13627 - so maybe just replace it? And what about just swapping main hdd controller that is 88i6522-lg01 that is in my case. I also read that flash could be inserted there if there is no rom chip on pcb.

If I would go for advanced diagnostics what they could do? What ttl tutor could do? There were infos on the net to put such devices to serial port but my hdd is parallel IDE? I also read there that with pc-3000 it could be repaired the broken flash on pre-amp or so - is it real to cure the issue how much it could cost if it is so simply relevantly (it is found on article about hot swap § smart hot swap). I also was told by phone by local master that changing the flash rom need special tools and some scanning for surface?? Is it such complex in that case to replant the flash. And if there were over-tensure twice or thrice of 12v/5v what could happen if you suppose - for that NIDEC FDC spindle. Did it surpassed some diode fuses, pcb chips and invaded platter?? Should I bought exactly the same sp0812n model for pcb replacement, or even platter swap that I improbably allow myself now. It cost about 5-7 euros in my european eastern country (not Russia).

From this


It seems your pc is not working. You would need to fix it before considering if the hard disk is bad or not.

Have you taken the hdd to some experient computer technician to test ?

Perhaps this tutorial could help?

http://www.users.on.net/~fzabkar/HDD/Tu ... 0411N.html

... or these?

http://www.users.on.net/~fzabkar/HDD/TVS_diode_FAQ.html

PCB protection devices:
http://www.hddoracle.com/viewtopic.php?f=100&t=1615

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A backup a day keeps DR away.

1. I tried my hdd in pc service hd testing and in fellow master. 2. Where is Firmware Version and how to get know it if hdd is out of busy? What is NOR Flash m29f? 3. Can I just replace vcm (spindel) chip or main controller? 4. How can I know that I need just try to replace pcb or swap platters? ... And probably the pcb schema is not needed as, without magnifying glass, I read approximately the marking of black boxes on my pcb. As it names is about -ae c544 - and BUX -c543 - that is relevant to instructions of https://community.wd.com/t/hdd-tvs-diode-faq/14692 it seems that they are exactly tvs-diodes, despite the first one is by the side of 5v rail and the second one is far from 12v input despite opposite of it. Indeed as the above link tells the tvs appeared in the midth of 2000s, so my hdd is of 2005 production. Although at the beginning of exploration of my pcb I thought that tvs is some kind of light-brown rectangular boxes such ones as from this link with pictures http://www.hddoracle.com/viewtopic.php?f=100&t=1615 that one that is directly oppositely of GND on one of pics. What are that brownish?

AE and BUX are the 5V and 12V TVS diodes, as you have said.

544 and 543 are YWW (Year/Week) date codes, ie weeks 43 and 44 of 2005.

Did you measure the diodes?

If you upload a photo of your PCB, I can help you identify the onboard voltage test points, assuming my SP0411N tutorial is not helpful to you.

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A backup a day keeps DR away.

Do the weeks of 2005 means? I would not measure these diodes, so I hope so kind of master would do it. If so should they to bad (0 and indefinite ohms in difference direction) should I just change them, how and in what way? Can it possible to replace correctly and it would work correctly after swapping?

If one or two tvs were broken after overvoltage does it means that spindel was unable to spin or the reason is also in something else in pcb board at least. Despite I assume if there are tvs diodes, overvoltage protection should work in such cases?!

"If one or two tvs were broken after overvoltage does it means that spindel was unable to spin or the reason is also in something else in pcb board at least" -- Yes, after radio-master measured the tvs-diodes, it showed that bux c543 (12v tvs) is broken as it shows just 1 Ohm in two directions. Meanwhile AE c544 (5v tvs) shows the about 0 and 550 Ohms in different directions, so it seems it is not broken. So, could just one broken tvs diodes stop the spindel spinning and resulting "non-definition" of HD? Radio-master, not inclusive in HDD pcb, assumed that broken tvs is the result of "burning" of some other more important component (chip), further in the citcuit, despite I think it contradict to the idea of tvs-diodes, despite I do not know the practice results. So could it be possible, that some other consecutive component in circuit is also broken?
Any way as I think -- to check if th issue is in 12 v tvs -- I just need to unsolder that diod and test my hdd on workable system wherether the spindel would spin and hdd would be defined. I think there is no need to find the replacement just now, just in case of desirable result?

So what i should do?
To Unsolder this diod and test hdd?
What is the probability that it help?

Remove the 12V TVS diode and power up the PCB on its own. If it seems OK, then attach it to the drive.

The TVS diodes are connected across the incoming supply. This means that they are damaged by external overvoltages, not by other components in the circuit. Ask your Radio-master to confirm that the diodes do in fact have continuity with the SATA power pins.

http://pinouts.ru/Power/sata-power_pinout.shtml

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A backup a day keeps DR away.

What do you mean by power up pcb? You mean pcb as hdd? If i power up just board how I see that spindel got moving if so? And hdd defined? I know that tvs burns out due to external overvoltage so what chances that overvoltage was stopped just by this one tvs and nothing more was reached by this voltage surge? Here is question should I unsolder this tvs from back side or front side of pcb, and if it possible that something could be damaged along it or some other element could be under it? One radiomaster measured it, but my neighbour could try to unsold er it and try plug hdd and test it but not the pcb itself?

Power up the PCB on its own to verify that there is no smoke or heating of components.

I can't answer your other questions until I see a photo of the PCB.

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A backup a day keeps DR away.

Now I understood that there can be anything else broken or burned - that I asked earlier. But I need to detach the spindle in this case. Anyway if it would help how reliable could be such pcb should I buy other workable pcb or hdd for it. I should note about sata - this hdd is of pata (ide). And what photo (i mention the model of board earlier so you can see it in the net) could be allow you to see if pcb is like new, and marking is hardly visible even for chip, I looked very attentively just to see very very small marking of tvs diodes (Concerning the tvs - are they the part of smd and why we can leave void tvs place, but we need the replacement of smd obligatory as I read on one site/forum on hdd?).

It happened. My local radiomaster unsoldered the 12 v tvs and one 0-resistor (that also appeared as the bad one) and hdd was defined in bios and spindel started to spin. Then I asked to find and copy some file to usb-drive. Now I need to find proper replacement: he soldered some replacement diode (m545 16 a) just after soldering out old one despite I persuaded him it is not necessary for tvs. So what replacement for BUX C543 I can find? He found replacement diod and probably 0-resistor from old pcb of another hdd.

You can use an SMBJ12A diode. See my FAQ for sources.

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A backup a day keeps DR away.

Should this smd be the same as my bux c543? Should it work as stable and long-term element? What parameters of bux c543 could to be as I did not found any info on it. Should any 12 tvs diod to be proper replacement? And what about 0-resistor -- how new non-native could influence the pcb and tvs as this resistor is on the circuit before bux?

And I did not found any info on M545 16a. What it could to be? Is it tvs or other type of diode, and can it be as replacement?