Hi everyone,

One of my old external hard drives stopped working (drive not spinning) a few months ago, but I just decided to fix it now because I realized I have some important stuff on there. It's an old "ExcelStor" drive. The drive isn't recognized by my PC or Mac. There's a small indicator LED light on the hard drive that works when I connect the drive to a computer, but the drive doesn't spin or make any sounds.

I think it's a voltage/PCB issue because I may have accidentally used a higher voltage adapter with the 5V port a while ago. I decided to open it up and check it out, despite being somewhat of an electronics noob. I heard that the TVS diode might have to be pulled out in order to get the hard drive working again.

However, I can't identify the where the TVS diode is on the PCB. I've attached a photo of the PCB to this post. If you need to zoom in, please right click and select "open in new tab". Sorry about the weird angle; the PCB is connected in such a way that I can't get a better angle. Any and all help in figuring out where the TVS diode is would be very much appreciated!

Thanks in advance!

Image link (too big to embed): http://i.imgur.com/4UwTTri.jpg

That's a photo of the USB bridge in your external box, not the PCB of the actual hard drive.

There is a diode (black component D1) but you're probably better off trying to connect the drive directly into PC with an IDE port if you have one. Or at least another USB box.

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I think the DIODE on the external case will be shorted, protecting the one inside the drive, if it has one, Just snip of the component at D1, or that black thing on the right of the picture and it might work.

Hi hdd2015

Do you have any electronics experience or gear?

Diagnosis is usually the first step and your reasoning seems to suggest over voltage.
Better to be sure though before ripping anything from circuit boards.

Be warned too that if any protection device is bypassed and there is still a a fault, then the next thing down the line will likely fry too often with more severe consequence. For example one should never replace a blown fuse with a metal pin.

there's quite a good background write up here
http://community.wd.com/t5/Desktop-Mobi ... d-p/250274

regards
Kern

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Thanks for the advice/help everyone!

@digitalferret
I don't have any serious electronics experience, but I consider myself fairly tech-savvy compared to the average person. I'll be sure to check out that write-up you linked. Also, I understand the risk of bypassing the protection device, but that shouldn't be a problem since the first thing I'm going to do once I get the drive up and running is backup all the data onto a new 1TB external HDD I have lying around.

I'm not sure about the actual hard drive's PCB. The hard drive itself is covered in some plastic for warranty reasons, but I can remove that easily. I'm at work now but will check it out when I get home in the evening. If I can't find anything, then I'll just try snip off the "D1" diode in the image I linked in the original post.

hdd2015:

check the write up first if you can.
The power problem usually gets by the diode in the case and blows the 12v one on the drives cct board.

Whatever, be sure that if you use the PSU supplied with the usb case, ensure it is trustworthy before snipping any protection off the hard disk itself.

I have one in here at the mo, and as per the writeup the diode on the case cct board is still good whereas the 12v on the drive tested bad.

If you can't grab a picture, at least see if you can find the make and model of the drive, as fzabkar requested, it would give someone the opportunity to point at things.

Alternatively as pcimage mentioned, maybe plug directly into an IDE equipped motherboard.

The usual symptom, if it is a blown tvs, is the PC will kick start briefly before the PSU protection sets in.
If so, then remove the diode, carefully.

the usual jurisprudence applies, don't be blowing anything valuable up in the process

good luck

Kern

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Когда хочется кушать – съешь всё.
Голод не тётка!

So, upon further examination it seems that the drive itself is a Hitachi HTS541616J9AT00 drive.

Here is a photo of the front, with USB bridge visible towards the top of the picture: http://i.imgur.com/1MfAvGi.jpg

Here's a photo of the other side: http://i.imgur.com/mGm08TS.jpg

I might just try pulling the "D1" diode on the USB bridge (as visible in the picture in my original post). If that works, then great.

Let us know.
As for me I'm off to Specsavers .... >.< *5v* ,--o.o

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Когда хочется кушать – съешь всё.
Голод не тётка!

Show us the interesting side, eg ...

http://i01.i.aliimg.com/wsphoto/v0/2048 ... A90002.jpg

Don't just "pull" anything. Measure it first.

Disconnect the IDE cable and retake the photos. Photos of the cable are unexciting.

_________________
A backup a day keeps DR away.

So I tried pulling the "D1" diode on the USB bridge but I couldn't really pry most of it loose. I definitely damaged the diode enough though. Still no luck. I'm thinking of getting something like this: http://www.amazon.com/Sabrent-Converter ... 00CPGYNV4/ in order to bypass the USB bridge and connect the drive directly to my computer. That way, if it still doesn't work, I'll know for sure it's an issue related to the drive's PCB and not the USB bridge? Thoughts?

Thanks again for all the help, by the way. It is very much appreciated!

Maybe go for native connector rather than X to USB.

http://www.amazon.co.uk/15Pin-44Pin-Fem ... B00LGKZ7DI

As with all adapters make sure you get the correct gender conversion for your device and risk as little as possible before plugging anything in, ie remove your main HDD from the loop if safe to do so.

I'm sure you know the score but check stuff like the PC is turned off rather than in sleep mode etc etc

good hunting

K

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Well, the main reason I'm looking for an X to USB connector is because I don't actually own a desktop PC lol. I have a Mac, and my parents have Windows laptops. Thanks for your constant help, by the way. I really appreciate it!

You live in New York, not a third world country. Surely you have a friend with a desktop you can use or borrow. Our just buy one off of Craigslist for $50. It doesn't need to be anything new or high performance.

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there are literally free or extremely PC's everywhere. I know because I have spent the better part of 2 days stripping and loading a trailer with all the ones I have accumulated in the last few months. It is going to cost me more to dump them that what it did to buy them!!

Haque: my image of you, given your propensity for 'fessing up about buying excess tech, is leaning towards digital "Bag Lady


..... ofc I don't have that much at all ....<eheugh>

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Когда хочется кушать – съешь всё.
Голод не тётка!

I can't be certain, but ISTM that D1 is probably an 8A 120V Schottky rectifier. The cathode appears to be at supply potential, but I can't see where the anode goes. Clearly it is not connected to the adjacent ground plane, so it may be that the diode is in series with the supply, possibly for non-destructive reverse polarity protection. However, if that were the case, then there would be an 0.4V drop in the supply voltage to the PCB.

Of course all this speculation is moot, now that the board has been destroyed.

BTW, removing a series connected diode would have broken a good board, so now we have potentially two problems.

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A backup a day keeps DR away.