So I've had a 1 TB HDD of mine sitting in the storage for about 7 years now. Now that's when i decided to finally try to attempt repairs on it i made some progress.

The fault was that the interface board was damaged when 13 yo me plugged the power connector upside down so that the 5v rail got 12v and vice-versa for the 12v. and in result the interface board shorted and when plugged back resulted out in the board just getting heated.

So i did took took out the board and found that the diode shorted out : https://imgur.com/EuDGKhi.jpg

then i tried to replace it from a donor board and might have successfully done it too : https://imgur.com/bV8SJyP.jpg

also the donor pcb isn't the same so i just replaced the diode and nothing else. Donor Board PCB : https://imgur.com/VOtA9Tc.jpg

Now the HDD spins and when connected via a SATA2USB adapter, it is recognized and even installs the drivers but no partitions or devices are detected in Disk Management and Device manager. Also i tried plugging directly into a PC but it's not detected in the bios although BIOS screen takes time to load when the HDD is plugged it (Maybe it's trying to read it) So before trying out anything else i just wanted to clarify on what i need to do next because i really don't wanna ruin it further.

Thanks, any help is greatly appreciated.

Whats the drives brand and can you post pictures directly to the forum, I cant load images from imgur.

It's WD Green and i've attached the images.

I'm not too sure how you can plug the sata connector the wrong way round, but if this is the case, I feel the damage might be extended. I am not sure but I think the protection on WD drives is crap and you could have a blown pre-amp inside the drive. I'm not sure others more experienced might know the answer. Wait for more comments and DO NOT OPEN THE DRIVE.

plugging the sata connector the wrong way should not damage anything coz it has on connections at the opposite side. It can be done if either the cable connector or the hdd socket is broken.
I guess it was attached to a Molex connector with a sata power adaptor cable and you reversed it at the Molex side, didn't you?

There are multiple problems:
-your donor pcb is not compatible with your patient drive, it is from a different family.
-the patient pcb is badly designed, it has the fuse (0ohm resistor) connected at a wrong location, thus providing protection for the TVS diode instead of the circuit behind it. So it is quite possible that the 12V entered into all the circuits running from 5V including the preamp inside the HDA, which means two additional things:
- not possible to recover without replacint the head assembly
- data may be severely damaged if a working pcb is attached to this HDD and started because the burnt preamp may feed current into the writing heads, which erases any data that comes its way.

So it is quite important to rule out every possibility before attaching a new pcb.

pepe

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Adatmentés - Data recovery

Pepe, to avoid this last scenario, what you would suggest?
Would you directly swap heads everytime you see shorted 5V line?

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My firmware database:
https://mega.nz/folder/O01DkBRI#MxP2J6ZNqXDcrX40I8MoQQ

i would test preamp.

pepe

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Adatmentés - Data recovery

You mean testing HDA pins with multimeter, right?
Which contacts need to be tested?
Is possible to kill preamp (if still is good) while checking it with multimeter due to its high sensitive to little current coming from the multimeter?

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My firmware database:
https://mega.nz/folder/O01DkBRI#MxP2J6ZNqXDcrX40I8MoQQ

ah, you probably were curious about the way to do it

there were a couple of threads about it but i will try to tell it in a nutshell:
- find out the location of power pins (PCB layout and multimeter will help you)
- measure power pins to GND using a multimeter in diode mode
- +5V should give you 1.6-1.9 roughly (black to GND and red to +5V)
- -5V should give around 0.2 (black to GND and red to -5V)
- measure reversely (red to GND and black to +5V), you should get around 0.6
- on -5V (black to GND and red to -5V) you should get around 1.6-1.9

you may also measure other pins and compare values to known good drive. Don't expect an exact match, especially if preamp manufacturer is different but a significant difference may be a sign of damage.

There is an even more precise way but i won't really go in that right here.

pepe

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Adatmentés - Data recovery

Very good explaination.
Thank you

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My firmware database:
https://mega.nz/folder/O01DkBRI#MxP2J6ZNqXDcrX40I8MoQQ

I try to guess it!
Voltage injection to HDA pins and measuring the voltage (or even better current consumption), without powering the spindle.
Is that right?

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My firmware database:
https://mega.nz/folder/O01DkBRI#MxP2J6ZNqXDcrX40I8MoQQ

yeah, start with line voltage...
no need to measure anything after that.

pepe

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Adatmentés - Data recovery

I actually was using a SATA2USB converter/connector for using it as a external drive, which is where the adapter had that Traditional Power Connector to Sata Power connector cable, which i happen to plug upside down while jamming it onto the power supply.


This is what i was afraid of.


I will never.

Yes sir.


I just took the Diode from it.


That now seems to be likely what it is. Also if power were to go to different parts of the circuit wouldn't they have blown up?




Aw, guess i'll just let it rest a year or two now.

Can i do this to check mine too?

Dunno, it depends on your skills in this field. In theory, yes.

check the 0 ohm resistor at the left of the blown diode (R67) with a multimeter in diode mode (continuity). It should measure as 0000 or close to that.
if it is broken open, then we can take it for 99.99% that preamp is busted. There a few members from India who can recover it for you.
Dunno, only Amarbir came to my mind but i am sure there were others as well...

pepe

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Adatmentés - Data recovery

Apologies for a late reply.

I have checked it and just checked again. The resistor is OK at 0ohm. So i guess the Preamp is OK?

that's something at least. However, it would be better to compare values at preamp connector to a good one.
pepe

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Adatmentés - Data recovery

Thanks, but how would i go about checking the preamp? Are there any tuts or guide i can follow?