Dead Xbox One S, Standby and 12V rail all OK, no shorts

This console has some slight liquid damage caused by humidity, not by someone spilling stuff on the Xbox. I took it as a challege but now I’ve hit a wall. All the Standy Voltages are Ok, (1.1V, 1.8V, 3.3V, 5V) but I just can’t get the console to turn on, not even a beep or the light from the front panel. I´ve changed some IC’s (U9C2, U9F1) and many resistors and capacitors. There are no shorts either. I do have a couple of resistors and capacitors that don’t look too healthy around a couple of RAMS, but I don´t think you need them for the console to at least give a beep, could it be a faulty Southbridge that’s just not generating the signal to turn on? have you guys encountered a similar issue?