WD2500KS-00MJB0 dead, wrong power connection

[marson]

Hi Everyone, This is my first post due to a sad story.

In short:
Model: WD2500KS-00MJB0
DCM: HSBHNTJAHN
PCB: 2061-701335-C00 AM (XC 2W19 27MN 8 0005280 7285)

i accidentally connected legacy power connector (4 wires) reversely and 12v went into 5v, 5v into 12v. Also GND was also changed.
Now when connected correctly chips U1 and U5 on PCB starts to heat very quickly( cannot be touched after 10-15 sec) and no spinning can heard on felt by touching.

Need opinion from experienced fellow members for PCB swapping.

Pictures attached:
http://imageshack.us/scaled/large/801/tikj.jpg
http://imageshack.us/scaled/large/20/t4sg.jpg
http://imageshack.us/scaled/large/4/zdr7.jpg
http://imageshack.us/a/img15/4197/i8c0.jpg

[jono-ats]

The topic of transplanting the ROM to another PCB has been documented scores of times on this website, and with just a little searching, you can learn all that you need to know.

However, in this situation, there is perhaps a >80% chance the preamp blew out as well. Lid alignment is critical and these are not simple to recover in any case. You can try another PCB, and maybe you will be lucky. But if not, this is a job for a pro, and not all can recover it successfully. There is almost NO chance for DIY.

[marson]

upon careful inspection R120 and 6 pin transistor (marked in pic) is burned.
http://imageshack.com/a/img849/4964/b6lm.jpg

so would the TVS saved the Preamp from this over voltage or not.

[jono-ats]

My guess is >95% chance that preamp is blown with these parts bad.

[fzabkar]

@marson, your board does not appear to have any TVS diodes. Therefore the preamp will have received the full force of the overvoltage on its +5V supply.

R120 and the MOSFET appear to be part of the preamp's negative supply, so this would confirm the likely failure of the preamp.

[marson]

Thanks fzabkar and jono-ats for the reply.

@fzabkar
can u Plz answer the following queries:

1- why don't WD have TVS Protection.(what were they thinking for not using TVS)
3- Does WD use TVS Protection in latest HDD or not.
2- if for instance WD2500KS have 3 heads, than all 3 preamp must be dead/burned by such over voltage.
3- will i require only preamp to be replaced or whole head unit.
4- if hdd is repaired, can it be used again in daily use
5- how much it will cost for repair HDD / recover data in this situation. (just an idea of cost).

Regards.

[michael chiklis]

Modern WD hdd have TVS protection but i see fail this protection very often on WD, Seagate drives are much better for TVS protection.
Preamp is on heads arm, so it's needed to change all heads.
In europe and in america cost a lot to change heads, about $600.
Try to contact someone in your country, contact waqas_ali766 on this forum, he is from Pakistan, he may help you.

[fitzhugh]

Did you have any luck with this drive? I'm wondering about the same model that I have that won't spin up.

I know this was a while ago, but I'm curious about those two components that you marked in the photo as apparently blown. On my hdd many of the components looked just like that - exactly like that to the degree I can tell in a photo - and it wasn't damage. Rather it was some of the black foam that is between the board and the rest of the drive when the board is in place. In my drive the foam had degraded a bit and was sticking the board to the drive like weak double-sided foam tape. It left crud like that on many components. They looked fried at first but lightly wiping them removed the crud and the components showed no visible damage afterward (no idea yet about damage I can't see since my multimeter is at work). After wiping the crud off the printed info on the components was still sharp and clear so I don't think it indicates anything other than, well, foam crud.

Obviously this is a bit late for you, and I could be wrong anyhow, but it might help someone else.

Thanks.