820-3476 no power

[Kyle93]

Arrived working but track pad was not functioning. Replaced trackpad with known good one and still was not working. After changing R808 board somehow died. Now PM
_SLP_S4_L and ALL_SYS_PWRGD are missing

PPBUS_G3H 12.60v

All 4 RTC signals are present.

while triggering SMC_ON_OFF_L

PM_PWRBTN_L drops to 0.34v

PM_SLP_S5_L no pulse

PM_SLP_S4_L pulses to 0.285v

PM_SLP_S3_L pulses to 1.6V

PM_SLP_S0_L constant present 1.9v no SMC_ON_OFF_L trigger needed

What next?

 

[2informaticos]

I think you've meant R4808.
Board turns on if you remove it?
Also try to start in SMC bypass mode.

 

[Kyle93]

yes and with R4808 removed board still does not start.

Same with SMC bypass mode

 

[2informaticos]

Check for short on all big coils.
You should get pulse on them, if PM_SLP_S4/3_L are pulsing (at same time).