820-00165 no power

[Kyle93]

Arrived with minor liquid damage around U501. Replaced U7501 and had fan spin and booting into OSX. A few days later board died again. PP3V3_S3 is low at 0.036V. Replaced U8010 to rule out but same issue. What to check next?

PM_BATLOW_L 3.3v

PPBUS_G3H 8.6V

PP5V_S5 5V

ALL_SYS_PWGRD 0.008V

SMC_PM_G2_EN 3.4v

PP3V3_S5 3.3v

 

[2informaticos]

"PP3V3_S3 is low at 0.036V"
Did you check 3V3_S4 first?

Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L.

 

[Kyle93]

3V3_S4 0.284V

PM_PWRBTN_L drops from 3.4V to 0.358V when SMC_ONOFF_L is triggered

 

[2informaticos]

Missing PM_SLP_S5_L too?
No oulse at all when you trigger SMC_ONOFF_L?

Check PM_SLP_SUS_L presence.
If not, check all RTC signals.

 

[Kyle93]

PM_SLP_S5_L 0v pulses to 3.3v from trigger SMC_ONOFF_L

PM_SLP_SUS_L 3.3V

 

[2informaticos]

Then all PM_SLP_Sx_L signals should pulse at same time.
Check that...

 

[Kyle93]

PM_SLP_S4_L pulses

PM_SLP_S0_L pulses

PM_SLP_S3_L pulses

PM_SLP_S3_R_L pulses

PM_SLP_S3_BUFF_L pulses

Yes all of PM_SLP_Sx_L signals pulse

 

[2informaticos]

OK, so all S4/3/0 voltages MUST pulse too; maybe not VCORE.
Check which one NOT.
Don't forget voltages from pages 57/58...