820-00165 PP5V_S4RS3 missing

[No-Clean]

Board was corroded around R5150, U6100 and U8160, all those chips were worked on and fixed, board worked fine for a few days and now it is back with PP5V_S4RS3 missing, diode mode here is correct.

PPBUS 8.6V
PP5V_S5 5V
PP3V3_S5 3.3V
PP3V3_SUS 3.3V

When I Trigger SMC_ONOFF_L there is a drop pulse at PM_PWRBTN_L and PM_SLP_S4_L

 

[2informaticos]

Do you note pulse on all big coils?
Check U1950 for corrosion.

 

[No-Clean]

No pulse board climbs up to 0.021A and stays there, U1950 reballed same thing.

 

[2informaticos]

If PM_SLP_S4_L pulses, you should note a pulse at least on 5V coil.
If PM_SLP_S3_L also pulses, then check other coils for pulse too.

 

[No-Clean]

Turns out now PM_SLP_S4_L is missing, I still get a pulse starts at 3.4V then drops to 0V on PM_PWRBTN_L when I trigger smc_onoff.

 

[2informaticos]

PM_SLP_S4_L pulses when trigger SMC_ONOFF_L (at same time)?

 

[No-Clean]

No, PM_SLP_S4_L is no longer pulsing when I trigger SMC_ONOFF_L

 

[2informaticos]

Then you have PCH related issue.
Check its basic signals, many times mentioned on the forum.