Hi experts, I have the exactly same problem described on this same forum of HDD Guru
Here: samsung-hd161hj-pcb-damaged-need-help-t17962.html
The power source was connected the wrong way to the box of the external hard disk (Samsung Sata disk 160G), burnt smell came out and now the disk doesn't work. The inside box has an obvious mark of the part overheated so no doubt on that diode being broken.

Sorry for the long post but I try to give as much detail as I can.

The disk is not being recognized by the bios. It used to cause the computer to shut down after power on (when connected), now the computer works fine, it just takes some time to pass the start up but the disk never appears. Yes the disk spins. The computer works just fine. I'm not using the external case anymore, I'm connecting the disc directly to the computer, inside of it.

What I already did:
1. I followed the descriptions on the thread about replacing the burnt diode. I can't get those parts here so I tried with some diodes I have within the voltage range. No luck.

2. I read on another thread on this forum about a guy who just took the burnt diode out (not replacing it) and he got away with it!. It was mentioned that the diode works as a power protection, and that the power from the computer was more secure. Well I tried that too and nothing happened. The disk still doesn't work, but it spins.

3. I bought a replacement disk, exact spects: size, brand, model, etc. I tested the NEW HDD and it was just fine so I replaced the damaged board and used the one from the new HDD. Didn' work. It was the only HDD I could found, it's been discontinued and after a long search, just found this one. No the HDD was not recognized by the bios, yes, it spins with any of the boards.

4. After some reading I took the chance on the "fridge" technique. I placed the HDD inside a plastic bag and cooled it down inside the freezer. Tried again but didn't work out. I opened the hard disk to see if there was any damage on the heads or plates but there is no sign of it. The HDD seems ok.


Could it be a difference on firmware that causes the board replacement to fail? shouldn't it be detected anyway?? Is there any low level tool that I could use to try to detect it? even when the bios fails?


I can't find any company dedicated to data recovery in my country . I would like to get my data back.


Any suggestion will be appreciated. Thanks in advance

This is wrong in so many levels.
First off, you did the freezer trick. You read about it. And of course you've heard of a thousand stories where they say this trick saved their data. If you visited this forum before trying this, you'd know this is all bollocks.
Secondly, you did read about the freezer (which has probably gotten your drive's situation worse), but did you also read that you shouldn't open the drive's lid on an un-protected environment? Opening the drive in a non-clean room, contaminated the platters with dust, humidity and debris. So, this has gotten things probably even worse.
Thirdly, when a pcb spins up the drive, then most probably that pcb is ok.
You said that when you power on the pc with the disk connected, the pc shuts down or doesn't power on? To me this means probably bad preamps. Then you said "now" the computer works fine. What happened between previous and "now"?
I'm sorry to say that this needs proper diagnostics. It is obvious by the so many "probably"s i put on my reply.
It is also obvious that your attempts are causing more harm than good.
If you care about the data on this drive, don't do anything else and consult a pro. It doesn't have to be in your country.

Good luck!

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Thanks, I'm to blame for all of that .

1. When attached to the external case, nothing happened
2. When directly attached to the computer, it refused to power on (electric problem)
3. Then it worked and since then the disk spins fine with the damaged PCB
4. The disk spined with the broken diode and without it
5. The disk also spins with the new board
6. The new board worked again with the new original disk

any suggestion before the dead end on sending it to another country will be appreciated

proper Pro. diagnose using Proper Pro. tools

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