WD5000AAJB don´t spin up + Smooth chip heats up fast

[leroy]

Hi I have a WD that doesn´t spin up if I try to power it up.
the only thing that happened is the Smooth chip get very hot.
I read in the Forum it could be a TVS Diode Problem, so I checked D4 + D3 + R64 + R67.
D3 seemed to be shorted and R67 dead so I unsoldered both part and give it a try but the smooth chip still heats up pretty fast and the drive still don´t spin up. Can anybody help? or is it a preamp failure

thanks

[leroy]

PCB 2060-701508-001 REV A
Marvel chip 88i6740-LFH1
Smooth chip L6284 3.1

[JGAN]

Something is causing the platters not to spin which causes the motor to draw a lot of current, either stiction or seized bearing or something. Will have to open it in a clean environment to see.

[fzabkar]

A shorted 5V TVS diode would suggest that the SMOOTH chip is probably dead. One would have to wonder about the preamp as well. Does the SMOOTH chip still heat up if you power up the board on its own?

[leroy]

A shorted 5V TVS diode would suggest that the SMOOTH chip is probably dead. One would have to wonder about the preamp as well. Does the SMOOTH chip still heat up if you power up the board on its own?

Yes the Smooth chip still heat up if I power the board on its own.

[fzabkar]

In that case the chip is dead.

I suspect that location U12 on your PCB is unpopulated, in which case you would need to rebuild the ROM data from the System Area on the platters. That's assuming that the preamp survived the overvoltage.

[leroy]

In that case the chip is dead.

I suspect that location U12 on your PCB is unpopulated, in which case you would need to rebuild the ROM data from the System Area on the platters. That's assuming that the preamp survived the overvoltage.

Yes the U12 is unpopulated
Is it not possible to swap the Smooth chip or the PCB including the MCU ? if no how can I rebuild the ROM data ?

[fzabkar]

You could try replacing the SMOOTH chip.

Otherwise you could try to gain access to the System Area (SA) on the platters with a closely matching donor PCB, and then rebuild the ROM "adaptives" from the SA modules. The cheapest commercial tool would be WDMarvel.

Regenerating a WD ROYL ROM from SA MODs:
http://www.hddoracle.com/viewtopic.php?f=59&t=761

[leroy]

if I have a donor PCB is it possible to swap the MCU and get the HDD to spin

sorry I am a noob

[fzabkar]

if I have a donor PCB is it possible to swap the MCU and get the HDD to spin

Yes, if it is OK, and if the preamp is OK.

[leroy]

I found donor PCB and attached it to the patient drive (want to give a try on rebuild the rom), unfortunately the drive just spin up and start clicking and after a while it shut it self down ? what does it mean ? is the Preamp damaged or is it something else

[drHDD]

Is this pcb from same model?

[leroy]

Is this pcb from same model?

the pcb has the same rev number 2060-701508-001 REV A and is also a WD5000AAJB

[drHDD]

It could be preamp, heads or your new pcb from drive which is too different compare to yours.