WD 1tb external hard drive wrong p/supply

richardeblack

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My apologies for starting a new thread on something discussed before, but I didn't get a reply from my question.
I have plugged a laptop p/supply into my WD elements external drive which has a WD Caviar Green 1TB drive in it. Disaster.
I assume I have blown the 12V TVS diode.
I have looked at the photos on the previous thread and my board is exactly the same as the one on Kase's drive.
I have checked the resistances and they are as follows

Pins 1 - > 3 Open
Pins 4 -> 6 0 Ohms
Pins 7 -> 9 open
Pins 10 & 12 0 Ohms
Pin 11 open
Pins 13 -> 15 4 Ohms

For 7 Pin Data Connector:
Pin one is farest away from 15 Pin Pwr connector.
Pins 1, 4, & 7 = 0 ohms
Pins 2,3,5,& 6 = Open (=>20 Megohms.[/quotemsg]

Do you think this might indicate a faulty diode which I could just remove, please?
Am I best to plug into my computer sata power and data, if I do, to reduce the risk of power surge etc?
There are no obvious signs of overheating except some discolouration, which seems to be present at several points. It did smell of hot electrics when I stripped it.
Can I just replace the diode with a 12V TVS diode, or will it be specific to the PCB? I have tried to track the numbers on the diode, to no avail.
I would be very grateful for your assistance.
Many thanks,
Richard Black.
 

richardeblack

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Thanks for the quick reply.
I think I would be pushing it a bit, as I actually fried it through incompetence (laptop p/supply). Also, I have dismantled it. Not even sure how old it is or where I got it from either. Could be over a year. Also, I would like to retain the data if possible.
Thanks though.
Richard.
 
Remove the 12V TVS diode and yes, you can replace it with any 12V TVS diode from another PCB. That said, the drive will work without the diode, but you will have no overvoltage protection.

Good luck.
 

richardeblack

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Thank you very much fzabkar.
I did read, as well, about the 0 ohm resister maybe being open circuit. Is it best to try it before shorting the 0 ohm resister, or remove it and short across, please?
I don't understand why they bother with a 0 ohm resister. Why don't they just continue the track?
If there is damage further down the pcb, is it likely to damage the platter of the drive, or the computer p/supply?
Many thanks for getting back to me.
Thanks,
Richard
 

richardeblack

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