Fail HDD from short circuit power supply

[rschan]

Hi all,

I just had some tragic incident, my chippie has the psu molex connector in reverse and shorted out 2 of my hard drive, both drive are not detectable now. I would like to gather some advice whether is it viable for me to rescue these drive.

both drive are from Seagate,

1. Seagate 250gb momentus board version: 100536286 REV E

I have probe the circuit board and found that the 250gb drive have a short circuit on the TVS diode, I had remove the diode and connect it to a usb hard disk reader but this has cause the hpal v1 to burn a hole, I suspect there must be some other part of the board is still having
a short circuit.

[http://imgur.com/a/0toTsIQ

http://imgur.com/a/JD0X56a


2. Seagate 500gb momentus board version: 100565308 REV A
The 2nd drive does not have a failed TVS, but when I connect it to the PC its has no motor spinning and detection.

http://imgur.com/a/KEyrFod

I would like to know that doing a board and bios swap will it be able to revive the hdd ?
what are the other things that I need to beware before doing the swap ?

[fzabkar]

When your drive sustains an overvoltage on the +5V supply, and if the 5V TVS diode fails to contain the damage, then one would have to be concerned about damage to the preamp on the headstack. You can measure the resistance at the preamp supply pins at the HDA connector.

BTW, here are direct links to your images:

https://i.imgur.com/ip4JwHt.jpg
https://i.imgur.com/NCKFK0v.jpg
https://i.imgur.com/4lLy1KY.jpg

[rschan]

can I know where should I probe to measure the resistance of the peramp headstack. which pin is for the preamp headstack ?