Ps5 slim EDM-040 beeps with light not powering on

PS5 Questions
1

Hi,

I am working on a PS5 Slim motherboard (EDM-040). When I try to turn it on, it beeps once, the power light turns on, and then it shuts off after 4–5 seconds.

I took some measurements, and all the fuses are OK. The PSU is supplying 12 V, but all the capacitors behind the APU are shorted to ground. Does this mean the APU is dead, or could it be a faulty Southbridge?

I also thought about connecting to the UART, but I’m not sure if it would be helpful.

Any guidance or tips would be greatly appreciated. It’s my first time working on a PS5, although I have some basic electronics knowledge.

Thanks in advance!

2

UART code definitely helps diagnose since you have beeps and light up for few seconds meaning all standby voltage, southbridge and 12v psu works properly.

It more likely pointing to CPU/RAM voltage related or something enables after power button press