I have been using a Seagate st300003u2 external HDD for many years now. Over time, I have gone through multiple desktops and laptops, and each time I stored my data on the HDD. It contains years of important legal documents, family photos, etc. Essentially, my entire life. Earlier today, I accidentally tried to power with my laptop adapter instead of the HDD adapter. The HDD will no longer power up. When I try to turn it on, the green light flashes for just a moment. I fear that I have shorted it out.

I know virtually nothing about HDDs, but I am willing to learn whatever is necessary to recover my data. Based on some internet research, I suspect that the diode burned out due to my use of the wrong adapter (but that's just my uneducated guess). If someone could help me to troubleshoot this problem and recover my data, I would be extremely grateful. Saving the HDD would be a great bonus, but really my main concern is recovering my precious data. Any assistance you can lend me is greatly appreciated.

Thank you for your time!

-Robert

Hello Robert

External drives has inside an additional circuit board connected with a 3.5" PATA(older drives) or SATA hard drive. Most chances are that this board is dead, but the drive inside will be ok.
So remove the screws on plastic cover (chassis) and inside you will find the drive.
You can attach it to your desktop internally or to another USB enclosure and power it up.
To get an idea:

My experience at Seagate's forum and others is that the drive's 12V TVS diode usually goes short circuit. Failures in the bridge PCB are comparatively uncommon, although I have seen a few.

I would remove the drive from its enclosure and test its diodes with a multimeter. If they test OK, I would then attach the drive to a SATA or PATA port on the computer's motherboard.

Detailed photos or scans of the PCBs would help.

_________________
A backup a day keeps DR away.

Thank you for your helpful responses! I am a complete neophyte at this. Do I need a torx screwdriver? If so, can you tell me which size I will need? I will order one online ASAP. As for the multimeter, should I buy one of those too or will it be prohibitively expensive?

A suitable digital multimeter (DMM) should cost no more than $10, possibly as cheap as $3.

See my FAQ ...

http://www.users.on.net/~fzabkar/HDD/TVS_diode_FAQ.html

... and http://www.users.on.net/~fzabkar/HDD/ (photo clips)

Some Seagate drives require a Torx 6 screwdriver.

_________________
A backup a day keeps DR away.