WD2500AAJS - 00B4A0 Salvage.

[Sheisty]

Problem: My drive does not spin.

Background: This PC (Dell Dimension 4600) generally runs 24/7 - 365 on a belkin surge protector. One morning the pc wouldn't wake the monitor from sleep/away mode. When I restarted the PC, all fans and drives would turn on, but the monitor would not respond. After troubleshooting it was said to be the PSU, Mobo, or RAM. So I inspected and reinstalled the ram one final time and fired up the PC. This time the fans started to spin up extremely fast and I instantly smelled smoke. I flicked the PSU kill switch off to prevent damage so I thought (whole process was about 10 - 15 seconds). Restart the PC and nothing powers up. The PSU is toast, and the motherboard is dead.

The next day I pulled the HDD's to salvage some data and neither would spin using an adapter. I used the adapter with another HDD and it worked. However, the two that were in the PC when i started to have problems refuse to spin.

There are no noticeable burn marks. 1 drive did have a light smell of smoke (no where near as strong as the PSU burn smell). That drive is irrelevant, the drive with the needed data (master) had no smell of smoke, and no visual signs of burns.

Questions: What should I do? Opt for a PCB swap? Or is there something else I should do first? (On the irrelevant drive I put it in a ziplock and froze it overnight and it didn't help one bit). The only thing i've done to the important drive is pull the PCB to check the underside for burns. I'll post pictures when I get home in a couple of hours.

Thanks in advance for your help.











WD Caviar Blue

WD2500AAJS - 00B4A0
DCM: DBNNHT2AGN
LBA: 488397168

[jono-ats]

Search forum: TVS

[Sheisty]

What does TVS stand for? I didn't get any hits with those three letters, and I don't recall reading about it in any of the threads i've browsed throughout the day. Thanks.

Got it TVS Diode.

[Sheisty]

Sorry for the back to back posts I couldn't edit the previous post.

Here are my pics as promised.







From what I've read the TVS is on the lower left corner somewhere.

[Nick_CT]

"A transient voltage suppression (TVS) diode is an electronic component used to protect sensitive electronics from voltage spikes induced on connected wires."

Loads of info on them within the forum. Basically you measure them with a multimeter on 200 ohm range. If it measures 0 ohms or close to it, you can remove it and hopefully the drive will spin up, albeit without the protection the TVS used to provide, so make sure yout power supply to the drive is good.

[Sheisty]

Thanks Jono & Nick.

I have a post PENDING Mod Approval with pictures and an explanation. On this particular PCB I believe there are two TVS diodes D3 & D4.

I'm going to pick up url=http://www.microcenter.com/single_product_results.phtml?product_id=0237694]this[/url] multimeter today to test those two to see if one or both of those diodes reads 0.

[Sheisty]

I got a 0.5 reading on D3. Should I remove it and give it a shot?

[Sheisty]

I've removed the Diode that had a reading of 00.5 and the drive still doesn't spin up.

Should I remove the other diode as well? I've read that I should test R64 and R67 on 200ohms as well. But I was a little bit confused with how to do it.

[Nick_CT]

In checking for shorts on D3 and D4 it doesn't seem that they were fried, so removing them won't solve the problem. I've found that when checking a dead PCB, and finding that the TVS diodes measure normal values, that the quickest solution is to just get a replacement PCB. If you're skilled in electronics then perhaps you could find the fault on the board and repair it, but I just replace the board if it's faulty and the TVS diodes aren't the problem as my electronics knowledge isn't great.

Check R67 and R64 for open circuits. You could probably replace an open resistor with a wire link, but my feeling is that a new PCB is needed. I've never gone down the 'replacing a resistor with a wire link' road before. However, the U12 position on your PCB is vacant which means doing a PCB swap isn't a DIY job. The adaptive information that you need to swap across to a replacement PCB is in the main controller chip, the big one with the 'M' on it. To transfer this information you need specialised and expensive equipment.

There are some places that will do this for you, whilst supplying the replacement PCB, at a price. I've never had to use any of these services though, so I can't comment on them. Just remember that fiddling with components on the PCB and the drive is a risk to successful recovery if you're not sure what you're doing.

[fzabkar]

D3 was bad. You should test R67 and R64 the same way as you tested the diodes. Both should read close to 0 ohms.

[BlackST]

Replacement PCB needs firmware reconstruction. It's gonna cost about the same as complete recovery even supplying a "compatible" PCB, a lot more if the HDA suffered damage too so it will be necessary to change headstack too. There are other ways but it's beyond DIY and involve use of specialized tools.
Last hope is to "revive" the PCB finding the fault , hoping the MCU is still working or at least working enough to read its contents.

P.S. the more the drive is fiddled with, the more the possibilities to make more damage.

[Sheisty]

Thanks for the responses. (FYI: D4 read 0.5 not D3) When testing R64 & R67 I was reading something about using sata pinouts for a ground as opposed to touching both sides of the resistor with the probes. I wasn't sure exactly how to do that.

When testing R64 & R67 without using a ground they both stay at the default reading of 1. If I can I will make a video to show exactly how I was testing the resistors.

FYI: I have a second drive that I can tinker with that has the same symptoms (see first post) that I can tinker with to learn. On this second drive I removed D3 & D4 but it refused to spinup as well. On the drive with needed data I removed D4 only. After I find out if i'm testing the resistors right I will put that drive to the side for the time being.

Photo of the meter I purchased and the default reading of 1 that I spoke of.



Photo of the PCB of the drive I NEED data from after D4 removal. (The yellow dots indicate where I was touch with the probes to get readings.

[Sheisty]

Any suggestions on my next move?

[jono-ats]

That "1" indicates an open circuit.

No offense intended, but apparently you aren't familiar with VOMs or working with circuits in general. It appears that the resistors may be bad. Replacing them is easy if you have minimal experience, but you may cause more problems or a disaster if you don't.

There is a reason why components have gone bad on your PCB. If you replace the bad ones that you find and apply power, you may kill something else (like the MCU or the preamp) if they aren't already toast.

I think you would be better served to get some pro assistance in this case.

[Sheisty]

I wanted to figure out a way to give it shot on the drive that has no vital info. I had the fortune of unfortunately ( ) having two drives with the same exact symptoms but only 1 has critical data on it.

In other words I want to tool around with the one unimportant drive to see if I can get it going again. Since R64 & R67 are open theoretically i could replace them some how with a wire link correct? What sort of wire would suffice?


I wouldn't be against mailing the needed drive to somebody for diagnostics though. Any suggestions on that end?

[Sheisty]

PS a bad PSU was the initial problem.

[BlackST]

In other words I want to tool around with the one unimportant drive to see if I can get it going again. Since R64 & R67 are open theoretically i could replace them some how with a wire link correct? What sort of wire would suffice?

NO !!

If they put two SMD resistors instead of a copper trace or wire, a reason must be (even if it is ignored).

I wouldn't be against mailing the needed drive to somebody for diagnostics though. Any suggestions on that end?

Diagnostics only or data recovery ?

[Sheisty]

Just as I thought I was understanding the situation a bit more I get hit in the head with a big NO


Diagnostics only. Unless its something that turns out to not to be so expensive. I'm to the point where I really want to know what is wrong with the drive.

[BlackST]

The "no" was LOUD, not BIG .

Seriously, the only diagnose with complete report should be not expensive at all. Maybe if you want a complete report it cannot be done for free, but probably someone with some spare time can take a look at your drive for a low fee. Just ask.

[Sheisty]

HEY,

Is there anybody out there willing to diagnose my HDD's issue?