Bmax B7 Power Mini PC interesting short diagnostic

[csberti03]

Hi!

I have this mini pc that doesn't want to start.
When I plug in the charger it goes into protection mode.

I check the input pins in resistance mode and they are not shorted.
But in diode mode its 0.174V

When I opened it up I saw something new, no input mosfet, just big diodes next to the charging port. I checked on the coils for shorts but didn't find anything suspicious. Only the CPU coils have low resistance but that should be normal because it's an 11th gen I7.

I injected some voltage to find the short but the board was only warm around the diodes. (there is nothing on the other side of the board there)
I checked the diodes they are SS54 schottky diodes in parallel.

D1&D2:
forward voltage: 0.174V
reverse voltage: OL

D3&D4
forward voltage: 0.174V
reverse voltage: 0.664V

The D1&D2 + is connected to the main positive but the D3&D4 isn't.
D1&D2 - and D3&D4 - have 0 resistance so I guess they are connected.

I would be glad if someone could help understand how this power circuit works so i can fix this computer.

[csberti03]

Here are some photos of it.