Data recovery and disk repair questions and discussions related to old-fashioned SATA, SAS, SCSI, IDE, MFM hard drives - any type of storage device that has moving parts
September 6th, 2016, 15:31
Pardon for my english...
September 6th, 2016, 15:37
The damage was already done. That's why the fuse was open.
At the moment you cannot tell which component is responsible for the low resistance. That's why you need to remove the zero-ohm resistors one by one.
Personally I would backup the contents of IC602, if you can. The data in this chip are critical and must not be damaged. At the very least I would refrain from powering up your board again.
There are suppliers who will provide a PCB plus "ROM" transfer for US$50. You might like to consider that option as well.
Edit: I would test the resistances of the motor windings.
September 6th, 2016, 15:46
Excuse me, which is the role off the zero resistances, i' not be able to backup the content if the ic. If a buy a pcb with the same serial? The fisical drive i hope is good? I burned this hdd when i connected it on a chineese led projector with a supplementary alimentation from a laptop. I burned projector, hdd and laptop mainboard. great error.
September 6th, 2016, 15:51
which is the role of the zero resistor?
September 6th, 2016, 16:01
I burned hdd connecting to a chineese led projector. It was not enough power and I put a additional power from a laptop . Result : burned hdd , projector and laptop motherboard.
That mistake!
If a buy same pcb (same serial) and replace the old, i' m not able to backup ic firmware?
September 6th, 2016, 16:08
I sent other posts but were moderate. Maybe because of my bad English . Anyway thanks.
September 6th, 2016, 16:15
Zero-ohm resistors are sometimes used in place of fusible resistors, but most often they are simply used to link two points on a circuit board. The manufacturer could populate the same location with an inductor or a fuse, but the resistor is cheaper.
PCB protection devices:
http://www.hddoracle.com/viewtopic.php?f=100&t=1615
September 6th, 2016, 16:31
fzabkar wrote:Zero-ohm resistors are sometimes used in place of fusible resistors, but most often they are simply used to link two points on a circuit board. The manufacturer could populate the same location with an inductor or a fuse, but the resistor is cheaper.
PCB protection devices:
http://www.hddoracle.com/viewtopic.php?f=100&t=1615
Yes but because two zero ohm resistor in parallel?
September 6th, 2016, 17:32
falco71 wrote:I sent other posts but were moderate. Maybe because of my bad English . Anyway thanks.
I can see one of your other posts. I don't know why it hasn't appeared in your thread. AIUI, you connected your drive to a Chinese LED projector. The projector wasn't able to provide sufficient power, so you supplied additional power from a laptop. The result was a burned HDD, projector and laptop motherboard.
As you have discovered, you should never combine the outputs of two or more different PSUs ... unless they have been specifically designed for this purpose.
September 6th, 2016, 18:22
falco71 wrote:Yes but because two zero ohm resistor in parallel?
They are not in parallel.
September 7th, 2016, 3:40
Thanks.
In summary :
1. I need to save the data of my IC602 . An identical pcb does not solve my problem. Can you tell me a site where i can buy the " ROM Transfer" ?
2. Then I can continue troubleshooting. But ...
What steps follow? Removing the zero ohm resistors that audits should I do ? Which capacitor in place of the lost ?
3. If the PCB is broken irreversibly I have to buy one just like it and transfer the data of the IC602. .
if I move my ic602 on the new PCB? it's risky? To be exact my hdd is a toshiba mk5065gsx A0 / Gj003a .
September 7th, 2016, 4:20
hdd-parts.com offers a PCB + firmware transfer for US$50. One forum member will sometimes do it for less.
I doubt that your PCB is economically repairable.
That said, the capacitor would probably not need to be replaced. It simply filters the 5V supply.
After removing the resistors, measure the resistance between ground and the right pad of each resistor.
September 7th, 2016, 4:37
fzabkar wrote:One forum member will sometimes do it for less.
This forum member?
September 7th, 2016, 11:41
It's me. I can provide board for less.
September 11th, 2016, 4:24
Thanks to the availability.
I thought , before repairing the pcb I would be sure that the hdd spins.
How can I test it ?
I have to apply voltage on which of the 4 pin connector on pcb ?
September 11th, 2016, 15:59
You cannot get the motor to spin by simply applying a DC voltage to the pins. The motor has three phases which must be commutated, ie pulsed in the correct order. The best you can do is to test the resistance of each winding with a multimeter.
September 12th, 2016, 7:07
The resistance between the first two points is 3,5 ohms and 5.5 ohms between the other two. (three phasis?)
Are they good values ?
September 12th, 2016, 17:07
Phase-to-common resistance should be half the phase-to-phase resistance. Your measurements look about right, but I suspect that the zero point of your meter is around 1.5 ohms.
In short, it looks OK to me.
September 12th, 2016, 17:35
Ok Thanks, I think it's worth trying the replacement of PCB .
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