BURNT PCB - WD1600AABS-61PRA0 (No ROM reading possible)

[reliableservice]

WD1600AABS-61PRA0
PCB S/N: 2060-701444-003 Rev A.

Problem :
Can't Read ROM or other data (even via Serial port).
Can't Regenerate the ROM

see the attach screen - what parameters to use to read all modules?
Searching modules in tracks, please wait.
\WDC Marvell\Sequoia\20210818-225401-0058007M\Data\Modules_SearchByTracks\
------------------------------------------------------------------
NN : Module ID : Cyl / Head / Sec : ABA : Length
------------------------------------------------------------------
(No Result)

FYI:
I have another working PCB with above serial number.

Any Help ?

Attachments

WD-What-Parameter-to-use.png (19.9 KiB) Viewed 14359 times

[fzabkar]

Can you read the ROM on the donor PCB? If so, then there may be a way to read the ROM on the patient, if the MCU is not damaged.

Can you show us a photo of the damage on the patient PCB?

For reference ...
https://sep.yimg.com/ay/yhst-44463692235217/western-digital-2060-701444-hard-drive-pcb-701444-10.gif

[reliableservice]

Can you read the ROM on the donor PCB? If so, then there may be a way to read the ROM on the patient, if the MCU is not damaged.

Can you show us a photo of the damage on the patient PCB?

For reference ...
https://sep.yimg.com/ay/yhst-44463692235217/western-digital-2060-701444-hard-drive-pcb-701444-10.gif

Can you read the ROM on the donor PCB? - Yes.
then there may be a way to read the ROM on the patient, if the MCU is not damaged. Not able to read.

Attach is Image

Thanks for the reply.

Attachments

[Lardman]

Crispy ! How on earth did that happen - You don't say if the drive is spinning - can we assume it spins with the donor board. Do you know what firmware versions the patient and donor are?

[fzabkar]

That's the inductor in the Vcore circuit. Did you test the 5V TVS diode (D3) and zero-ohm resistor (R67)?

Measure the resistance between R45 (R050) and ground. If that is 0, then the MCU is most likely damaged.

L2 looks a little bit toasty as well. This inductor is part of the negative supply for the preamp.

I would remove the damaged inductor. If there is no short to ground at R45, you could then power up the PCB and measure the voltage at R45. This should be around +1.2V. The voltage at Q4 (near SATA power) should be +3.3V (Vio) at the emitter (the lowest of the 3 pins).

Note that the damaged inductor is in parallel with a second inductor. I don't know how the circuit will run with a single inductor (assuming nothing else is damaged), so you may need to be quick with your measurements and ROM dump, if possible.

That said, you will probably find that the damage is not confined to the burnt inductor.

If the MCU is OK, but the Vcore and Vio supplies are not, then it may be possible to power up the MCU by using your donor PCB to provide Vcore and Vio. You would need to remove Q4 and R050 on the patient before running external sources to these voltages. The POK signal would be missing, so it may prevent the MCU from coming out of reset, but it would be worth trying.

[reliableservice]

Sent PM please check.

That's the inductor in the Vcore circuit. Did you test the 5V TVS diode (D3) and zero-ohm resistor (R67)?

Measure the resistance between R45 (R050) and ground. If that is 0, then the MCU is most likely damaged.

L2 looks a little bit toasty as well. This inductor is part of the negative supply for the preamp.

I would remove the damaged inductor. If there is no short to ground at R45, you could then power up the PCB and measure the voltage at R45. This should be around +1.2V. The voltage at Q4 (near SATA power) should be +3.3V (Vio) at the emitter (the lowest of the 3 pins).

Note that the damaged inductor is in parallel with a second inductor. I don't know how the circuit will run with a single inductor (assuming nothing else is damaged), so you may need to be quick with your measurements and ROM dump, if possible.

That said, you will probably find that the damage is not confined to the burnt inductor.

If the MCU is OK, but the Vcore and Vio supplies are not, then it may be possible to power up the MCU by using your donor PCB to provide Vcore and Vio. You would need to remove Q4 and R050 on the patient before running external sources to these voltages. The POK signal would be missing, so it may prevent the MCU from coming out of reset, but it would be worth trying.

[fzabkar]

Sent PM please check.

"Access denied"

[reliableservice]

Sent PM please check.

"Access denied"

sorry - now link is working (made unlisted.)
Pls click on PM link again to play.