First of all I am pretty much a newbie when it comes to actual hard drive repair and damage recovery. I do, however, have over 15 years of experience in software level repair such as using SpinRite and most common data recovery utilities. But what I have now is a 320 GB WD Caviar SE SATA drive that came out of an IMac that purportedly underwent a power surge of some sort...possibly even lightning coming through the power lines somehow. The IMac itself has been restored to working order with just a new hard drive but the original hard drive and its data cannot be accessed. When I tried to boot up an Intel based PC system with this drive installed as a secondary the system would not power all the way on and the power light blinked steady on and off. My understanding of this POST code is that there is a direct short somehow in the hard drive, possibly even by design to prevent further damage to the drive. The end-user would really like to get the data off this drive if possible so I am asking of you hard drive gurus out there for possible troubleshooting steps or repair recommendations. I do have some pictures of the drive and circuit board if they would be helpful. The drive is a model WD3200AAJS and the controller board part no. is 2061-701444-000 AD. Any help would be appreciated.
Thanks, Brian

You posted the following on 5/12/2010:
imac-hard-drive-damaged-need-advice-t17883.html

Is there any reason that you are reposting essentially the same question?

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A backup a day keeps DR away.

All I can say is I am sorry for the posting foul. To be honest I was not sure which was worse forum etiquette, posting to a 6 month old post or starting a new one on the same topic so I am sorry if I have annoyed anybody. I do realize that the people who know what they are talking about and monitor these threads don't have time to mess around so if you think it would be better I will go back to the old thread.

You didn't upset me.

I was merely surprised.

That said, did you test the TVS diodes and zero-ohm resistors?

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A backup a day keeps DR away.

I thank you all very much for your patience with me. One of our clients had major lighning damage from the recent storms so I have been out of town for most of a week and am just now getting back to test the system. I did the tests you described and here are the results as best as I can tell. Both resistors R64 and R67 are around 1.3 ohms. D3 shows 500mv one way and open circuit the other way (I think this is normal). D4 on the other hand is an open circuit both directions so I am sure that is one of the main issues. Any advice on next steps is much appreciated.

If the client's data is important, wouldn't it be better to outsource to a lab who can recover the data, rather than risking losing it all? Of course, if the value to their data is less than a couple hundred dollars, knock your socks off.

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Luke
Recovery Force Donor Inventory: 5,000+ Fully Cataloged HDDs & Growing

try wrd pro tool hope u will get solution

AIUI, the usual failure more for TVS diodes is short circuit, not open circuit. (I assume you measured D4 on the diode range of your meter.)

If you are happy to continue with your measurements, then there are several voltage test points for you to check. Let me know if you wish to proceed.

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A backup a day keeps DR away.