820-00165 not turning on.

[BCN_Techs]

Got this board. All s5 rails are present. No water damage. Just stopped working.


ALL_SYS_PWRG is 0V. When i connect magsafe fan doesnt spin but board pulses all s0 rails for a second than stays in s5 state.

In SMC bypass fan spin and stop twice and than nothing happens.


The only rail not present when plug is PP5V_S4RS3 (pulsing twice to 5V and goes to 0). Already checked and changed U7501 with no result


Any idea?

 

[2informaticos]

Mnay times, two pulses is just sign of bad CPU.
You should start checking all SPI Bus Termination resistors and traces.
Also try known good BIOS.

Do you get pulse at PLT_RESET_L too?

 

[BCN_Techs]

PLT_RESET_L pulses twice and stays 0. Bad CPU?


SPI Bus Termination resistors and traces.( will check this but i think it's waste of time)