Wd caviar wd1600 not spinning up after pcb and u12 swap

[Cribbyrhymes]

I'm hoping someone can help me. I think I may be at the data recovery company stage but I may be missing something. The hard drive was in an external enclosure and after a pc move to another room I must have accidentally hooked it up to the wrong power supply as I could smell burning and the drive wasn't spinning up. I quickly switched it off and after removing the pcb seen that the u1 chip was fried. After doing some research I purchased a replacement pcb online and I'm sure that all the numbers that need to match do. I then had an electronics shop do the u12 swap. I fitted the new pcb, connected it to the external enclosure and fired it up. Nothing happened, no spin up or noises of any kind. The drive wasn't recognised in windows. I connected it directly to the pc internally but exactly the same outcome. If I hold my ear really close to the drive when it's powered up I can hear a faint buzzing sound and the u6 chip gets really warm very quickly. I have attached pictures of the hard drive, old burnt pcb, new pcb etc. Any help would be greatly appreciated. Thanks

Attachments

[labtech]

Use search function with keyword "preamp".

[fzabkar]

Measure the resistances between each pair of motor terminals.

[Cribbyrhymes]

thanks for the reply fzabkar. Sorry for being a complete noob, I can work a multimeter but where are the motor terminals? Would you be able to explain this in more detail for me.
Thanks

[data-medics]

think I may be at the data recovery company stage

I agree. I think what Fzabkar is saying is that the drive likely has internal issues, possibly heads stuck to the platters.

[thatdellguy]

What you do to the drive at this current stage will determine its outcome. If you value your data send it to a professional. Whatever you do, don't open the drive. It will only make it worse and more expensive.

[fzabkar]

I can work a multimeter but where are the motor terminals?

There are 4 pins connecting the motor to the PCB. The resistance between each pair of terminals on the motor (not on the PCB) should be of the order of 1 - 2 ohms.

Code:

                 Common
                   o
                   |
                   |
             +-----+-----+
             |     |     |
             |     |     |
             C|    C|    C|
   1-2 ohms  C|    C|    C|        Spindle Motor windings
             C|    C|    C|
             |     |     |
             |     |     |
             o     o     o
             A     B     C

If the motor is OK, then you may have a stiction fault.

Head stiction video by Waqas Ali:
http://www.mediafire.com/download/cvo59 ... k_head.zip

Waqas Ali is a SalvationData trainer:
http://www.alexsoft.org/viewtopic.php?f=88&t=622&p=1671

Of course he would normally perform the procedure in a cleanroom or clean chamber, and he would be wearing gloves.

Attachments

WD1600BB_motor.JPG (51.71 KiB) Viewed 15151 times

[Cribbyrhymes]

Ive measured the resistance across the motor terminals on the HDD with the following results

1-2 = .001
1-3 = .001
1-4 = .001
2-3 = .002
2-4 = .002
3-4 = .002

Does this mean that the motor is broken?