Hello
is there a fuse because it seems dead.

Can you measure the voltages across each of the capacitors?

Can you identify the markings on the diode and IC1-6?

Is there any identifying text near the "test points"?

Can you provide more detailed photos of the areas in the attachments?

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A backup a day keeps DR away.

I've never had a WD SSD in my lab I'm also interested in how this goes for you. Also what controller do they use?

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www.falxdatarecovery.com.au
Gold Coast, Australia.

IME when people ask, "is there a fuse", that's usually the limit of their ability. Moreover, when the photo lacks any discernible part markings, that's another telling indicator.

_________________
A backup a day keeps DR away.

I was hoping the OP might want to go further as it does sound like a electrical issue. With a perfect donor and enough parts replaced I can see getting at least a diagnostic hoping the the controller is not damaged in the process.

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www.falxdatarecovery.com.au
Gold Coast, Australia.

As far as I know, the controllers on these WD SSDs are encrypted.

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Yevgeniy. No, NOT Malkin.
Ambassador at ADRS®

Western Digital bought SanDisk, thus all their controllers should be SanDisk.

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Luke
Recovery Force Data Recovery

https://www.windowscentral.com/western-digital-3d-nand-blue-review

NAND -- SanDisk 64-layer 3D
Controller -- Marvell 88SS1074

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A backup a day keeps DR away.

The WD Black PCIe 512GB SSD uses a Marvell 88SS1093 controller. Its power management IC is "9040VM409".

The WD Blue 1TB uses a Marvell 88SS1074 controller and a 9040VM509 PMIC. I suspect that IC1 is a 9040VM509.

The "S" logo belongs to Active-Semi Inc. I suspect that the actual part numbers are ACT9040VM409-T and ACT9040VM509-T. I can't find any data at active-semi.com, so I suspect that these ICs may be special orders for WD/SanDisk.

The ACT88320QI-T appears to be a similar IC, although it incorporates 3 buck regulators compared with 4 for the ACT9040. However, the ACT88320 does have an EXT_EN pin which enables an external buck regulator. I suspect that the ACT9040 may integrate this additional buck to minimise the part count.

The ACT88320 also has 2 internal LDOs, one of which is switched off when the IC is configured for an 88SS1074 controller. I suspect that the ACT9040 would also have an LDO, although it could be external rather than internal.

Here is the datasheet for the ACT88320:

ACT88320QI-T, Active-Semi, PMU IC, 2.7V - 5.5V in, 1 x 4A buck, 2 x 2.5A bucks, 2 x 200mA LDOs, QFN-32:
https://active-semi.com/wp-content/uploads/ACT88320_Datasheet.pdf

The part number decodes as follows:


The CMI (Code Matrix Index) option identifies the IC’s default register settings. For example, CMI 105 is optimized for the Marvell Dean 88SS1074 microprocessor.

CMI 101: ACT88320QI101-T -> SMI SM2258, SM2258XT, SM2259 and SM2259XT
CMI 103: ACT88320QI103-T -> Atmel SAMA5D21 processor
CMI 104: ACT88320QI104-T -> Silicon Motion SM2262 and SM2263 ICs
CMI 105: ACT88320QI105-T -> Marvell Dean 88SS1074 microprocessor
CMI 108: ACT88320QI108-T -> Silicon Motion SM2258

Therefore, I suspect that the ACT9040VM509 is a 48-pin device with a profile which is optimized for the 88SS1074, whereas the 409 profile is optimized for the 88SS1093.

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A backup a day keeps DR away.

Based on my examinations of other WD SSDs, I suspect that IC4 may be a high-side power switch under the control of the DEVSLP pin.

PMPB20XPE, NXP, -20V, -10.3A, P-channel Trench MOSFET, marking 1D, DFN2020MD-6 (SOT1220):
https://assets.nexperia.com/documents/data-sheet/PMPB20XPE.pdf
http://chip.tomsk.ru/chip/chipfile18-x.nsf/all/C3479264BEB2373C46257DC1001E5E49/$File/PMPB20XPE.pdf

I believe that the diode is most likely a 5V or 3.3V TVS diode.

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A backup a day keeps DR away.