Lenovo 15iml05 Power led lights for 12 seconds then off 12 seconds

[liquidzorch]

Hello. I bought a faulty Lenovo ideapad 3, but it turns out the 3Valw buck converter burnt a hole through the board. I was able to clean it up, and remove all the shorts. I now can power the 3.3v rails from a bench power suppy while connecting the laptop to its psu, and I get the additional 5valw, 1.8v, and 1.05v, form what I can tell in the schematics, those are the only 4 voltages I should see before turning on, and they are present. When I hit the power button, the power indicator on the left side turns on (not the one on the power button), stays on for about 12 seconds, then turns off for about 12 seconds, in an infinite loop. While on, there are no additional votage rails. From what I understand, the next rail to go high should be the SYSON, but it stays low.

I already tried to flash a know good bios I found here, but the same thing.

Any ideas? What signals should I be looking for? According to the schematics, after power button is pressed, it checks the S state (that is something I don't understand) then it starts the SYSON, so, if I understand correctly, I am between these two stages.

[reformatt]

Simulating a voltage isn't enough as the associated power good signal would be missing.