820-3462-A A1425 Doesn't see ssd

[tipoti]

820-3462-A A1425 ssd doesn't appear
I think they tried a ssd converter on it and now not even its original ssd appear.
I get 3.3v on J4500 as instructed by its schematics.
Where should I focus now?
(Smc...) (U4900....) It goes through U4900. Could the problem be on U4900?
Device works but ssd doesn't appear at all.

 

[2informaticos]

Boot USB macOS and check if internal SSD is at least det4ected in Disk Utility.
This test is good to discard a problem with partitions; like deleted, or APFS.

Check first L4500/10.

 

[tipoti]

hi,
i already checked it L4500 i wrote above text (I get 3.3v on J4500 ) so do i need to check U4900 (Smc) ?
And also I checked ssd cable and tried diffrent cable but doesnt see ssd. And i checked ssd with different device, it works.

 

[2informaticos]

"i already checked it L4500"
What about L4510?

 

[piernov]

Remember to change the view in Disk Utility to show all devices and partitions rather than just valid volumes.

 

[tipoti]

I get 3.3v on I4500 and 5v on L4510 but this line cannot be used for SSD. I think it's SATA GUMSTICK2. For normal HDD, I get 3.3v on 1 to 14 on J4500. The owner said that it's been like this since they tried to replace the SSD.

 

[2informaticos]

Then check for knocked off components, or broken traces.

 

[tipoti]

SATA_SSDRHDD_D2R_P , SATA_SSDRHDD_D2R_N, SATA_SSDRHDD_R2D_P, SATA_SSDRHDD_R2D_N
There are 4 lines through the hdd socket, none of which seems damaged.If you could be more explanatory, I can move forward more easily Could you give me directions from the schematics on which path should I take or which lines should I test?

 

[2informaticos]

Check R4506/07/08/10 and C4517/18/22/25.
Also check diode mode to ground on these lines.

Try known good SSD flex too.
Do not trust new chinese bulshits.

 

[tipoti]

 

[2informaticos]

You should check diode mode to ground on data lines.

 

[2informaticos]

SSD data lines have series caps.
Did you check diode mode on the PCH's side of them?
You can also check the other side, when SSD is connected.