HD154UI - Will not spin.

[kilbert]

hello,

I had a faulty drive tray, that shorted out 3 drives. The problem has been fixed, but I would like to try to salvage my stuff on the drives. I understand I may make the data irretrievable, and I am ok with that. I figure I have nothing to lose, and an education to gain.

I read through the forum and performed what tests I could. I tested the TVS and they appear faulty. They are not "open" in any direction,. I read resistance in both directions. I cannot locate the "fuse" or 0 ohm resistor. The one I did find, may be OK (measured .3ohms)

I have not continued (cutting the TVS) as I am not sure I have done enough to ensure the drive will turn on (eg I did not find the fuse)

Please see my album: http://imgur.com/a/MXXff

Thanks in advance!
John Kilbert

[fzabkar]

Remove the 5V TVS diode and flow a blob of solder over the fuse. Then measure the resistance between the +5V and Ground pins at the SATA power connector. If there is no short circuit, then power up the board on its own. If OK, then try it on the drive.

Alternatively, you could test the HDD by bridging the fuse with sharp pointed tweezers (after removing the 5V TVS diode).

[kilbert]

Sorry, I am unsure which part is the fuse. Can you help?

is it this:

[fzabkar]

I forgot to upload a photo. Sorry.

Attachments

HD154UI_TVS.jpg (115.54 KiB) Viewed 11102 times

[kilbert]

Thank you for the help.
If I short my leads my meter reads 000, across those the sata pin pairs (10-12 & 7-9) I read .447 ohms or 1.97 ohms, depending on the pair tested.
There is continuity, but some small resistance measuring between the 5v and gnd at the sata connector with the resistor fuse jumped.
The board is still attached to the drive.

How should I proceed?

This is what it looks like now: http://imgur.com/QcvebVb

[kilbert]

I thought I replied to this, but it is not appearing. I think it may have to do with the fact I placed a link on the post.
From memory:

I de-soldered the 5v TVS, and bridged the fuse. I measure some low value resistance about 2 ohms IIRC (but not a short) from the 5v sata pin to the gnd sata pins. The resistance varied depending on the pin pair measured (there are 3 for each). I posted a picture in my album (in post 1 of this thread) if you wanted to see it. The suspect 12 v TVS is still attached & the board is still attached to the drive.

How should I proceed ?

[fzabkar]

Pin #1 is grounded at the PSU, but not on the PCB. It is used for staggered spinup control and as an activity LED output.

It appears that the PCB still has a short circuit somewhere, or perhaps the preamp is shorted. I would remove the PCB from the drive and retest the resistances.

[kilbert]

I removed the board, I get .452 ohms from the ground to all pins of the +5 connector. I also get .663 from ground to all the +12 v pins. There is no obvious burn marks or popped component (at least to my untrained eye)

Thanks for your continued assistance.

[fzabkar]

I would measure resistances using the 200 ohms range rather than the diode test range. However, it now appears that the short circuit is in the preamp inside the HDA.

[kilbert]

Yes, Sorry. I was on wrong range. I changed to auto range (from diode) & I changed the battery in the meter. I get varying results depending on the pin pairing.

assuming pin 15 is the one on the right when looking at it (nearest 12 tvs)
pin layout:
15,14,13 = 12v
12,11,10= gnd
9,8,7=5v
6,5,4= gnd

On auto setting & board removed Readings:
from pin 12 to 9,8 &7 =2.4k
from pin 11 to 9,8 &7 =14 ohms
from pin 10 to 9,8 &7 =2.4k

Are those numbers better?

[fzabkar]

Yes, that's better.

I'm not sure about pin #11, but your PCB does not have a short across the +5V input.

Now repeat the measurements with the PCB on the drive. If you now measure 2 ohms rather than 2.4K, then this will prove that the preamp is dead.

[kilbert]

With the board re-installed I measure close, if not the same as above. I believe this is sounding promising.
How should I proceed?
Thanks!

[kilbert]

Well, it works! Thanks for your help.
I would like to actually fix the drive, do you happen to know the part numbers for the 5v tvs & fuse?

Thanks again
John Kilbert

[kilbert]

Wow. This has been fun! Having not touched a soldering iron in over 12 years, it felt good to do this!
Thank You so much for sharing your knowledge.
Applying the information from this drive, and your help fzabkar I also got the 2nd (HD103SJ) of the 3 drives to work!! the only difference is the fuse is marked 000, and a lot larger.
I would like to replace the fuse & TVS on this one if you know the part number also.
Thanks in advance!

[ShaneWard]

if you got some old drives lying around just take it off them, or buy some online at ebay that are faulty (None PCB issue) and remove them from the PCB.

Glad it worked out anyhow...

Shane

[kilbert]

I was hoping got just order the components new. Probably a lot cheaper than a drive, since I have 3 drives with the same TVS blown out & 2 different resistors.

[fzabkar]

See Q3 in my FAQ:
http://www.users.on.net/~fzabkar/HDD/TVS_diode_FAQ.html