MacBook a1502 only sound that turns on and does not turn the fan heats

Hello friends, I just received an A1502, you only hear the classic sound of turning on macbook, but the fan does not turn and nothing appears on the screen, heats cpu.

could you help me how to start the diagnosis,

thanks

Angel

hi Friends.

to comment that it detects short in mosfet pashe1, replacement and ppbus_g3h : 12 volt

now I don't have pp5v_s5, and read that ppv5 voltage is more complicated to detect

some help now replace smc reset and u7501

thanks