820-00165 no power after liquid damage

[werickoliveira]

I have a Macbook Air 820-00165 that had liquid damage, in the visual analysis identify the capacitor c2952/53/50, all with visual oxidation, putting the pp3v3_S4 mesh in short, after removing these capacitors the mesh returned to the standard diode mode.

I have a lack of voltage in the PP5V_S4RS3 mesh, any tips on what to do.

measurements

PPBUS_G3H -> 8,56V
PPVRTC_G3H -> 3,3V
ALL_SYS_PWRGD -> 0V
PP5V_S5 -> 5V
PP5V_S4RS3 -> 0V
PP5V_S0 -> 0V
PP3V3_S5 -> 3,3V
PP3V3_S4 -> 0,303V
PP3V3_SUS -> 3,3V
PP3V3_S3 -> 0,038V
PP3V3_S0 -> 0,055V
PP3V3_S4SW_SNS -> 0,034V

 

[2informaticos]

Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L (at same time).

 

[werickoliveira]

I did the procedure, measured the pulse drop, 3.3V PM_PWRBTN_L
when triggering on SMC_ONOFF_L the voltage drops to 0.3V

 

[2informaticos]

Check for pulse at PM_SLP_S4_L, at same time.

 

[werickoliveira]

I measured PM_SLP_S4_L 0V and triggering SMC_ONOFF_L it remains 0V

 

[2informaticos]

No pulse at all?
Did you check it at same time when trigger SMC_ONOFF_L?
If yes, then you have PCH related problem.

 

[werickoliveira]

yes I tested it, thank you.

 

[2informaticos]

So pulsing, or not?