PS5 Slim Beep No Light UART DDR4 Error

[ChattFix]

Hello everyone, I need some help with a PS5 Slim board EDM-040 that will beep but no light or fan spin.

When I connect my bench power supply, (12v 0.500amp) the amps go between .135-.035 then back to .005.

When I attach UART I get the error code below. I have replaced the DDR4 ram IC with one from a donor board. Cannot verify is the IC was working or not, still same error.

[Slot #] [Date Time] [Error Code] [Priority] [Error Message]
00 5/27/2024 4:25:40 PM 80871001 Low DDR4 Error (Power Failure or Short Circuit)
|-(OK 00000000 80871001 17554CCE FFFF0042 10000000 2038 0004 FFFF FFFF:C4)
Click for TSB Information

Any help or suggestions would be appreciated!

[ongobongo]

measure the ram power rail for shorts first. If there is no short, measure the rail in voltage mode when powering on and post the results here

[ChattFix]

measure the ram power rail for shorts first. If there is no short, measure the rail in voltage mode when powering on and post the results here

I'm getting all the correct voltages according to the picture below. I also get the 1.2v on the side with the DDR4.

[ongobongo]

Check for shorts underneath the southbridge.
Also check for voltages underneath southbridge, those rails will come up when you hit the power button

[ChattFix]

Check for shorts underneath the southbridge.
Also check for voltages underneath southbridge, those rails will come up when you hit the power button

Do you have any measurements I should be looking for?

[ChattFix]

Check for shorts underneath the southbridge.
Also check for voltages underneath southbridge, those rails will come up when you hit the power button

Found a short on this cap. Going to remove and see what I get.

[ongobongo]

Desoldering the cap will change nothing.
If you have a short underneath the southbridge it's 99,9% a faulty southbridge.
Desolder sothbridge and check for shorts again. If short is gone, you have your fault

[ChattFix]

Desoldering the cap will change nothing.
If you have a short underneath the southbridge it's 99,9% a faulty southbridge.
Desolder sothbridge and check for shorts again. If short is gone, you have your fault

Lol yes I meant the SB when removing. Removed the SB IC and short is still present.

[ongobongo]

I don't have a EDM-040 board here, but after looking at the some google pics, measure around the IC top-right to the SB (CPU side up, USB/Hdmi-ports left). That should be the power supply of the SB