GB RTX2080 Super - crash on load > second switched 12V instability > what is purpose of this circuit?

[ktmmotocross]

Hello.
Have this GB 2080 Super that crash on load. When half load i see instability on one of two switched 12V rails. I dont know its purpose and dont have BV or Schema for this board.

Can anybody explain me what is purpose of this two switched 12V lines?

[ktmmotocross]

i see it is called steering or Input switch rail ballance

[ktmmotocross]

found one mosfet with G-S short. after replace it work