So a friend's hard drive died. he carried his laptop to his neighbor's house and came back and it computer locked up and then wouldn't recognize his drive. the reader arm moves and the disc spins like normal. but the computer won't even show there's a drive connected.

i've come to the conclusion that the most economical repair i can do for him (because i'm not cleanroom specialist) is to replace the PCB from another drive.

Current Drive model:
MJA2250BH
CA07083-B50400AP

Possible PCB Donors:
1-MJA2160BH
-CA07083-B52200C1

2-MHV2080AT
-CA06557-B39300TW

3-MJA2320BH
-CA07083-B52600C1


The only difference i can see (other than the numbers) is the size of the disc storage. i assume that option 1 and 3 are the best since the numbers are closest. but should i look for a drive that is the same storage size? i've spent all day looking and i can't find a 250GB. these three are the closest i've come.

so question is... can i use any of these drives as a donor for the PCB? or do i need to keep looking a MJA2250BH drive to use as a donor?

-What I Wonder
(Wonders what I am)

Unlikely that you have a PCB issue. Problems is elsewhere, thus requiring a more through analysis by using an array of tests to isolate the issue.

Suggest you stop powering the drive on until you have a solid plan on how to move forward.

Is the data really important?

_________________
Hard Disk Drive (HDD), Solid State Drive (SSD, SATA, NVMe, etc), USB Flash Drive and RAID Data Recovery Specialist in Massachusetts

what kind of tests can should i run? and is there software that i'll need for it?
what kind of problem are we looking at?
what are my options for repairing the drive?

i would rather be able to recover the information. but if not, i know it's much easier to just replace the drive completely.

I would say seek professional data recovery help OR get a new drive via warranty if still under it.

_________________
Hard Disk Drive (HDD), Solid State Drive (SSD, SATA, NVMe, etc), USB Flash Drive and RAID Data Recovery Specialist in Massachusetts

That doesn't answer my questions, nor does it help at all.

I'd like to be able to fix this myself. i am a fairly good technician, i just haven't worked a lot with dead hard drives. i usually just replace them. but it would be very nice if i could replace or repair something and be able to at least get his data back.

so, replacing the PCB wouldn't fix anything? are you sure?

As Labtech already has stated: before thinking about how to repair the disk, you should diagnose the problem properly.

[tounge-in-cheek]
Insisting on changing the PCBA to fix this problem is like saying "The engine of my car is broken. But since I am not good with engines, I will rather change the tires to fix the problem". Might work if it turned out the tires actually were the problem. But not likely.
[/tounge-in-cheek]

It is not possible to do a precise diagnosis based on the information in your first post. But platters spinning and actuator arm moving, does indicate that the PCBA has successfully completed it's initial tests. Although problem can be related to firmware, it is more likely a problem with r/w heads or platters. Based on that the disk died after laptop being carried back and forth to the neighbours. Possibly with hdd running?

If the disk is spinning fine with no clicking or rattling sounds, you could try to connect it to another PC/laptop to see if it is detected by BIOS. Just to rule out any problems related to your friends laptop.

@whatiwonder,

do one thing only but do it right : connect the disk to a DOS based PC that run MHDD and select the disk.
If it is stuck BSY it's not the PCB and NO, a straight PCB swap doesn't work.
If the drive comes ready and you can access data on it, it's not the HDD.
If you see PWD lit , the drive is locked.
If you see other weird things like HPA lit (that is not supposed to be) then we'll think about it later.
If it is a firmware problem there's nothing you can do as expensive equipment is required and you have to work it out on your own (assuming you can).

P.s. READ AND UNDERSTAND THE MHDD MANUAL first.
And don't forget that many MHDD commands ARE destructive so PAY ATTENTION !
If you don't feel confident or you don't want to risk, just give up. Better safe than sorry.