Question Used wrong PSU cables for HDD, 5V TVS Diode has Resistance in both directions, Small Fuses are Open Circuit

[Canuckle17]

HDD: Seagate ST1000DM010
PCB: 100774000 REV C

I accidentally used the wrong modular PSU cables to power my hard drive and am trying to save it.
How should I go about fixing the PCB?

Any help is appreciated.
Thank you

 

[TerryLaze]

What do you mean?! You already found the faulty components so you now replace them.

 

[fzabkar]

Remove the 5V TVS diode and retest for shorts at the diode pad. As for the "fuses", they are probably just zero-ohm links. Depending on your soldering skill, you can replace each pair with a single smd 4A fuse, or you can bridge them with a blob of solder. The latter has risks, so you need to decide whether the risk is acceptable to you.

If you upload a photo of the PCB, I'll help you to locate any further damage. That will give us more confidence in the repair.

 

[USAFRet]

The best solution is to replace the drive, and recover the data from your backup.

Second level is to follow fzabkar into a possible ficx.

 

[Canuckle17]

Here is the PCB:

I was going to remove the 5V TVS diode but saw it wasn't shorted. I got worried since I've seen these shorts in most other threads.
The marking on the diode is 6BE.

For the zero-ohms, could I swap them for zero-ohms from another Seagate hard drive? Different model, however. What are the risks of shorting the zero-ohms with solder?

Thanks for the help

 

[TerryLaze]

For the zero-ohms, could I swap them for zero-ohms from another Seagate hard drive? Different model, however. What are the risks of shorting the zero-ohms with solder?

Thanks for the help

As long as you check them and they are working, they are all the same, as long as it fits.
The risk of shorting them with solder is that they won't do their part of protecting the rest of the board, they will still make the board work, if nothing else is wrong, but you won't have protection.
But this is visible with the naked eye so you can just try again.

 

[fzabkar]

Measure the resistance between Ground (any screw hole) and V1, Vneg, 5V & 12V TVS diodes, and each of the test points in regs.jpg. Use the 200 ohms range of your meter.

https://i.postimg.cc/qRFHYxJ6/12-V-TVS-Diode.jpg (12V TVS diode)
https://i.postimg.cc/J7yshTBg/5-V-TVS-Diode-V1.jpg (5V TVS diode and Vcore)
https://i.postimg.cc/MpwHdqr2/Vneg.jpg (negative preamp supply)
https://i.postimg.cc/26g8vDBt/Regs.jpg (Vio)

Edit:

I think I may have identified the diodes incorrectly. The diode nearest the SATA power connector could be the 12V diode, in which case the "lonely" diode would be the 5V diode.

 

[Canuckle17]

Here are the resistance measurements

1. V1:52.2 ohm
2. Vneg:0L
3. 5V TVS:
   1. Leftside: 0L
   2. Rightside: 0.002ohm
4. 12V TVS:
   1. Topside: 0.002ohm
   2. Bottom: 0.002ohm
5. Chip left of mosfet:
   1. Top: 0.008ohm,
   2. Middle 0L,
   3. Bottom 0L
6. MOSFET:
   1. Left side: All 0L,
   2. Rightside: All ~33.6 ohm

 

[fzabkar]

It's the 12V TVS diode that's shorted. If you remove it, and the short is cleared, then you should be OK. All other measurements seem OK. At least there are no shorts. (see my edit)

Just retest the zero-ohm resistors. I would have thought that the pair at the left-hand edge would be open while the pair nearest the 5V diode would measure 0.0 ohms. If a pair is open, you can replace both with a single 4A fuse. Otherwise, depending on your skill, you can flow a blob of solder over them. That entails an element of risk, so it would be best if you used an external enclosure with an AC adaptor. These are current limited by design.

Make sure that your PSU is good. Also make sure you are using the cables that came with that PSU. That's because modular pinouts are not standardised.

Edit:

I may have mixed up the diodes because the PCB layout is very strange in that area. Nevertheless, the procedure remains the same, ie remove whichever diode is shorted. You can do this by snipping its pins with flush cutters.