# [SOLVED] Seagate Barracuda burnt circuit board - DIY Fix?



## Jake77 (Nov 30, 2010)

Seagate Baracuda 7200.12 1TB
S/N: 9VP5TPQD
ST31000528AS
P/N: 9SL154-515
Firmware: CC44
DateCode: 10381
Site Code: TK

This is a friends external Seagate drive that stopped working. I've removed the drive from it's enclosure and removed the circuit board. On inspection the circuit has been burnt below the SATA power input.

See attached Pics:


As you can see two small transistor fuses ( I think thats what they were ) are totally destroyed. The two TVS diodes are intact but I think one of them is dead. The left diode gives a multimeter reading on the 2000 OHM setting of 481 with no buzzer alarm the right diode gives a reading of 001 with alarm sounding.

My question is can I somehow bypass the fuses if thats what they are?
Can I make some kind of temp repair, so the data can be backed up?

Any help is appreciated.


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## raptor_pa (Dec 5, 2008)

*Re: Seagate Barracuda burnt circuit board - DIY Fix?*

That looks like some pretty heavy damage, the traces may well be burnt there also. Do you have any idea what happened to cause those devices to go? If you do fix it, the protection will be gone, if there is a bad power supply, or another failed component on the drive itself downstream of the protection, then you will cause additional damage to the drive. You also need to check the diodes in both directions. A failed diode will conduct in both directions, a good diode in only one. The other component is likely a 0 ohm resistor being used as a fuse, even though it is not exactly the same thing. With this amount of damage, it will be important to understand what exactly happened when the drive failed. You mention it was an external drive, was it perhaps connected to an improper power supply?


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## Jake77 (Nov 30, 2010)

*Re: Seagate Barracuda burnt circuit board - DIY Fix?*

The hard drive and enclosure are Seagates own product and was only used with the proper power adapter.

External Drive S/N 2GHLAKAZ
Power Adapter 12v 2A

The drive was set to power on with the PC although the USB connection wasn't always plugged in.
Not sure what may have caused the damage.

How would you go about fixing the drive so the data can be recovered?
I know that I can snip one side of the TVS Diode/s but what about the other two fuses that are burnt beyond recognition? Can I bypass them or use a substitute component?


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## Jake77 (Nov 30, 2010)

*Re: Seagate Barracuda burnt circuit board - DIY Fix?*

Ok, found the following advice on another forum in relation to a similar problem to my own. 

<A href="http://www.users.on.net/~fzabkar/HDD/ST1000528AS_fix.jpg" target=_blank>http://www.users.on.net/~fzabkar/HDD/ST1000528AS_fix.jpg

I would remove the 12V TVS diode and the damaged inductors (?). Clean up the charred area with a toothbrush and isopropyl alcohol (audio/video tape head cleaner). Then solder a wire between the two white boxes marked "+12V". This will restore the connection between the 12V terminals in the SATA power connector and the +12V rail on the PCB. If there is no other damage, the drive should work OK, but it will no longer have any overvoltage protection on the +12V supply.

The damaged on the controller looks identical to damage on my controller card.

Do you think this solution will work?


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## raptor_pa (Dec 5, 2008)

*Re: Seagate Barracuda burnt circuit board - DIY Fix?*

These are not fuses per se, First of all you will need to identify the missing components to be sure before jumping them out. I doubt they are inductors ( colis) as identified in that other article, but if they are, simply jumping them out may or may not work.


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## Jake77 (Nov 30, 2010)

*Re: Seagate Barracuda burnt circuit board - DIY Fix?*

Thanks for the help. I think I'll try jumping out the damaged components to see what happens. I'll be plugging this into my external SATA connections incase the USB HDD enclosure was the source of the fault.
I'll post back here with the results.


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## Jake77 (Nov 30, 2010)

*Re: Seagate Barracuda burnt circuit board - DIY Fix?*

Ok promised to post back with the result of the DIY fix and very pleased to say it worked like a charm.

I've backed up my friends precious photos (including his wedding photos first 2 kids pics etc.) onto DVD. Think he needs to buy me a drink for this. :wink:

I followed the advice and removed the burnt components and sniped out the 12v TVS Diode. Then I connected a wire from 12v SATA Power point to the right-hand contact that the removed 12v Diode was connected to.

I should have photographed the controller board before I reassembled but the following photoshopped image should make it more clear.


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## cbdatabases (May 22, 2011)

I had virtually the same problem as displayed above with a Seagate Barracuda 7200.12 Seagate external drive, 100536501 Rev A board. Bought a caddy for £25 which proved to me that the drive wasn't spinning. Bought a Seagate Barracuda drive 7200.12 drive with a 100536501 Rev B PCB for £46, swapped the boards and my old drive started spinning but the data could not be accessed. Finally followed the steps in this post, cleaned the burnt board and soldered a piece of wire on and hey presto board spinning and flies retrieved. 

Jake77 and Raptor_Pa thanks for your posts and pictures above they have been a fantastic help.


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## Jake77 (Nov 30, 2010)

cbdatabases thanks for the reply, I'm glad this has helped someone else.


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## ghanashyaml (Oct 22, 2009)

*Re: Seagate Barracuda burnt circuit board - DIY Fix?*



Jake77 said:


> Ok promised to post back with the result of the DIY fix and very pleased to say it worked like a charm.
> 
> I've backed up my friends precious photos (including his wedding photos first 2 kids pics etc.) onto DVD. Think he needs to buy me a drink for this. :wink:
> 
> ...


I have a similar burnt/fused component but is near the 5v SATA input. The issue is mentioned here:Re: ST31000528AS Barracuda 7200.12 PCB replacement - Seagate Community Forums.

I am still confused about the solution. You mentioned you removed the 12V diode, then what about the left-hand contact? Would it not be disconnected with the right-hand contact? Did you short that too with a wire or replace it with a new diode?


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## raptor_pa (Dec 5, 2008)

The diode can be left out of the circuit for recovery purposes. That diode only conducts on an overvoltage condition to shunt the voltage directly to ground to prevent damaging other components. The board will function normally without the TVS diode - however you must be certain your power supply is stable as without the diode there will be no overvoltage protection for the rest of the board.


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## ghanashyaml (Oct 22, 2009)

OK, final questions, after that no more bugging!

Which direction should the diode conduct, from left to right or right to left (As per the earlier image)? If it is conducting in both directions, then it has too burnt out, right?
In case the diode is working correct, can I keep it in still there (may be a silly question?) and can still have the overload protection or does the diode and the other component work in conjunction?


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