Fix and Repair a Dead Hard Drive

Everyone’s got a story about losing important data one way or another, whether it’s from the accidental deletion of some files, a stolen computer, or more commonly a failed hard drive.

To be honest I’ve never been a casualty to lost data, I always kept backups… probably too many backups… like backups of backups. To others it’s “a lot of work”, probably because they don’t have a good process/mechanism in place or they are “limited” technologically and that’s fair.

It’s never fun thinking about what you can’t get back when your hard drive goes belly up… but what if you could get it back and fairly painlessly. Well if your hard drive is dead, toast, caput, it just might be salvageable as I found out this week when a friend of my sister’s dropped off their hard drive to me to see if their life memories could be retrieved.

The hard drive is a Seagate, model ST31000528AS, it’s a 1 TB SATA 3.0Gb/s.

It would not power on at all, my first inclination was obviously something on the PCB (Printed Circuit Board) has gone awry. First things first, let’s remove the PCB so we can take a look at it. This may require a torx screw driver, most techies will have this on hand.

Now the first place to check is the two diodes on the PCB. You want to check the resistance of each diode, if the resistance on either is very low then there is a good chance that removing the diode will resurrect your hard drive. The diodes act as a circuit protector (similar to a fuse), when there is a power surge it “takes one for the team”
to prevent damage to other circuitry.

Notice when I test the first diode, the resistance is fairly high, it’s measuring approx 48K. This diode is OK.

However, when I measure the 2nd diode the resistance is almost nil. This diode is bad.

Simply desolder this diode, reassemble the PCB to the hard drive, cross your fingers and power it up.

If it worked, great! Remember though, going forward you no longer have the circuit protection unless you replace the diode you removed. If for whatever reason there is another power surge you probably won’t be so lucky.

Now go and backup that hard drive so next time this happens you can get a good night’s sleep!