I was able to copy the EC/KBC. I'm attaching it in case it needs cleaning/modifying. It's KB909022Q.

Currently, the device charges the battery, but when it's turned on, the blue LED flashes, activating the 3V3ALWS, 1V8, and 1V05 sources (in addition to the 5V and 3VLP sources already on S5). However, after 8 seconds, it shuts off and remains on S5 again.
The EC sends the BTN_ON signal to the PCH, but I don't see the PCH outputting the S4 and S3 signals.

Thanks for everything....

Hello everyone.
I had to replace the PCH on this computer because it had an internal short circuit.
Can someone clear the PCH BIOS for me?
ACER PREDATOR HELIOS 300
GH51M LA-K862P Rev: 1A
PH315-53-72T7
S/N NHQAUEB0011080A4793400

Thank you very much....