Seagate 7200.12 wont power up/spin

[Soooooz01]

Hi

My daughter used the wrong mains cable to plug the external drive in. I removed the external drive from its case so that I could connect it direct to my laptop. When I connected the drive using may SATA/IDE ADAPTOR it started to smoke now it won't power up or spin. It is 1tb of family memories and other backups. Have I fried the PCB? Can anyone help or guide me how to retrieve the data from this drive. Unfortunateley I cannot afford to send it away and I am quite comfortable doing smilar repairs, I just need guidance please. Many Thanks

[jaclaz]

Hi

My daughter used the wrong mains cable to plug the external drive in. I removed the external drive from its case so that I could connect it direct to my laptop. When I connected the drive using may SATA/IDE ADAPTOR it started to smoke now it won't power up or spin. It is 1tb of family memories and other backups. Have I fried the PCB? Can anyone help or guide me how to retrieve the data from this drive. Unfortunateley I cannot afford to send it away and I am quite comfortable doing smilar repairs, I just need guidance please. Many Thanks

What happened is hard to say, but from what you write it is possible that the disk has NOT been damaged (much)

All modern hard disks have a kind of "fuse" (actually two of them, one on the 5V and one on the 12V ).

They are not actually "fuses" as we normally know them, if they are triggered they short to ground.

Technically they are called TVS diodes, see:

http://en.wikipedia.org/wiki/Transient-voltage-suppression_diode

If the TVS(s) worked as they should have been:

• when the disk is powered by a "proper" power supply (with short protection) the effect is that the PC won' t start at all or very quickly shut down.
  
• when the disk is powered through an (usually el-cheapo) external power supply such as those you find in external cases and "SATA/IDE adaptor", which have not such protection the effect is that the power supply fries .
  

So, maybe, you are lucky and you just fried the sata/ide adapter power supply because the disk protection actually worked and the TVS (either or both of them) shorted the power to ground.

If this is the case, besides getting a new power supply for the adapter (or buy a new complete set, most probably cheaper) all you need to do is to verify that the TVS are shorted (any common multimeter will do) and remove them (by desoldering them or CAREFULLY prying them out of the disk PCB).

Please consider that without the TVS's in place the PCB has NO protection against overvoltage/overcurrent, so the idea is first get another new hard disk and use the old one in this unprotected setting ONLY for the sheer time needed to image it over the new one.

Later, and depending on how cheap you are, you may think to get a couple of TVS diodes from another disk you can find as scrap and re-solder them.

It is fairly easy to "spot" the TVS(s) on a PCB, example:

If you need help in finding them, post a picture of the PCB.

jaclaz