WD 500GB PCB Replacement - Spins but does not read

[Anon]

Hello all!
I am so glad I found this forum, packed with info!

I'm not a total noob when dealing with computers and parts but hard drives arent my speciality, so I need some help with a crashed hard drive.

I have a 2 WD5000AADS, one of which has a burnt PCB (actual burn marks on SATA and power connector pins). I was thinking of replacing the PCB with the other drive's PCB.

Both drives have the same model number (WD5000AADS-00M2B0) and same date code but differ in DCX and DCM. I am not sure which of these matters the most but my question is if I can somehow use the healthy PCB for the crashed drive. I tried a simple swap and the drive spun up but couldnt be read (says in windows that i have to inititate it, which means I would lose the data).

Should I swap the u12 chip ive seen been discussed in some of the threads here? Or is there another way to solve the problem?

[dmarques]

Hi,

When you swap the PCB, you could see the drive in BIOS and inside Windows?
If you got a message inside Windows to initialize your drive, means that the PCB is compatible (means you're very lucky).
If so, you should have access your data. If you haven't might be a logical issue. For that you can use a recovery app to get the data.

By other hand, are you sure you aren't using your donor drive and that's the one that got recognized inside windows?

[BlackST]

If the PCB was REALLY "compatible" (1 out of 100'000 so play lottery ) the drive should have been seen without problems with all structure , albeit with "other" problems... there is the possibility to have the drive inited correctly (FW/SA) but not fully visible to the OS but it is VERY UNLIKE... (luck is blind)

[Anon]

Hm, I was TOLD that it was recognized and Win wanted to initialize it but I tried it now and no, it doesnt show up. So I guess it's not compatible after all.
Recovery apps dont recognize it either.

Suggestions?

[dmarques]

Well, at your own risk you can swap ROM (U12), it has any external ROM of course. Or else, go to a pro and get proper help if you data is valuable.

[Anon]

Any harm to the data itself if I swap the ROM chips? And does swapping only include simple unsoldering/soldering the chips?

[Nick_CT]

If this drive has an 8-pin EEPROM chip at U12 then maybe this will help:

u12-swap-experiment-t17494.html

Does the drive spin up, click a few times and then spin down, or just spin up and make 'normal' sounds and stay spinning?

[Anon]

Yea, it has the external 8-pin chip. Spins up, normal sounds and stays spinning.

[Nick_CT]

I'm definitely not a pro or guru but I feel that this isn't a DIY job, if it's spinning then it's most likely a problem with the SA or something else that will need professional intervention. I could be wrong.

[dmarques]

The problem is that there's risks on swapping chips, specially if you don't have experience. Worse thing you could do is burn ROM chip, and in that case, things would be harder.

[Anon]

Do you mean the soldering procedure itself? I won't be doing the soldering, got a technician for that =)

My main question is: If i get the chips swapped (by a pro), is there a risk for irreversible damage to the data by only trying to spin up the drive? Never mind the PCB, can get another one of those.

[drc]

If i get the chips swapped (by a pro), is there a risk for irreversible damage to the data by only trying to spin up the drive?

I recently saw a case with a burned pcb where the preamp inside the drive chassis had also burned and deposited smoke all over the platter surfaces. Then the client had tried to swap boards and run the drive, and the heads hit the smoke particles, grinding them over the surface.

Last edited by drc on December 2nd, 2010, 10:53, edited 1 time in total.

[dmarques]

Probably the risk to the data is low. Main problem is not if you damage the PCB itself, as you said, you can get another one. Problem is if damage original ROM chip. That is not easy to replace.

But if your tech has experience, you can try it out and check the results.

[Anon]

Ok. I will consider doing it then but probably go to a pro instead.

Thanks for all the help!

[dmarques]

At least that way you'll get a quote, and then you can decide between that and the value of your data.

[Nick_CT]

If your data's important to you then it's in your best interest to get it done by a pro. As mentioned there are numerous (if not low risk) risks. The ROM chip could get damaged. As mentioned there could be platter damage that could be made worse by spinning the drive up again and again. You don't really know. If you want to experiment then you've been given a fair bit of useful information here. If not, then send it away and pay the $$$. Good luck!

[fzabkar]

Any harm to the data itself if I swap the ROM chips? And does swapping only include simple unsoldering/soldering the chips?

Yes, it's a simply soldering job that any junior technician should be able to handle.

That said, can you upload photos of the original PCBs? Many times the damage is restricted to TVS diodes (D4 and D3 ?), in which case the solution may be much easier, and cost you nothing.

[Anon]

I dont really know what to photograph but here are a couple of images at least:

http://img221.imageshack.us/g/img26210.jpg/

[fzabkar]

http://img818.imageshack.us/img818/428/img26240.jpg

The image is unclear, but diode D3 and resistor R67 appear discoloured. Check their resistances with a multimeter set to the 200 ohms range. If the diode is shorted (ie if it measures close to zero ohms), cut it out with flush cutters. If the resistor measures zero ohms, leave it, otherwise replace it with a short wire link, or bridge it with a blob of solder.

If there is no other damage, then the drive should work without the diode, but you will no longer have overvoltage protection on the +5V supply, so be absolutely certain your power supply is good. For continued protection you can replace the diode with an SMAJ5.0A from Farnell, Mouser, Digikey.