Ps5, no 3.3V_SOC_V33_S5

PS5 Questions PS5
1

Hi, I am troubleshooting a PS5 with a long blue light and no boot and I found something odd.

All the standby rails look fine, so I used my bench power supply at 12 V, 1 A and compared behavior to my only known good board, an EDM-033. On the good EDM-033, the TUSB1044 shows up clearly on my thermal camera when I power the 12 V input. On the EDM-020, the TUSB1044 stays cold.

I traced this to the fact that it was not getting its 3.3 V. On EDM-020 that 3.3 V comes from IC7106 (3.3V_SOC_V33_S5). IC7106 is receiving 5 V on its VDD pin, and nothing around that rail looks shorted, so I replaced IC7106. The rail still does not come up and TUSB1044 still does not heat, which is confusing because I do not have another EDM-020 to compare, so I am not sure how this rail is supposed to behave on this chassis. It is possible that on EDM-020 the TUSB1044 just does not warm up the same way as on EDM-033, but right now it looks like 3.3V_SOC_V33_S5 is missing.

From what I understand, 3.3V_SOC_V33_S5 is a standby rail, but:

  • IC7106 is getting 5 V and ground

  • The 3.3 V rail does not appear shorted

  • The output still stays at 0 V

IC7106 on EDM-020 also has other pins like CE and CS. I suspect one of those might be preventing it from turning on, but I cannot confirm, and I do not have an EDM-033 schematic or an identical circuit to compare the CE and CS readings with. The other ICs that look similar on the EDM-033 board are used for different rails, so I cannot use them as a direct reference.

In short, I am stuck at: IC7106 has 5 V in, the 3.3 V rail is not shorted, but there is no 3.3V_SOC_V33_S5 output. Any insight on how IC7106 is supposed to be controlled on EDM-020, or what CE and CS should look like on a working board, would help a lot or literally any insight would help lol. Thank you!

2

Pin 3 CE of the IC7106 is the enable line (PSW_MSOC_PGA3) which comes from the southbridge.
I would inject at the CE pin 3.3V and see if pin 5 has an output of 3.3V.

3

yup, that worked! but what does that mean now… is southbridge broken? it lights up in my thermal camera so i thought it was working.

4

So the question is why is the EN signal not coming from the southbridge.
It could be an error in sequence before the enable signal should be switched on or the southbridge is bad.

Do you have checked the UART error codes?

5

yeah, its constantly C0020303, does not show anything else at all, even when i wipe the error logs. ive checked the board multiple times for liquid metal spills and ive found none, bigger problem is that this ps5 came in with a white light and only hdmi being broken but now it has a constant blue light and everything else seemed fine before. on thermals there seem to be no shorts inside the apu so i dont think liquid metal got inside of it. i was told that if southbridge wasnt working then UART wouldnt work but the fact that it did leads me to beleive it does work so im just confused at what it could be.

6

Can you post the whole UART error string?