820-3437 the PP3V3_S4SW_SNS is missing

a 820-3437 board has orange light on the charger, all the S5, S3 and S4 rails are present except PP3V3_S4SW_SNS
U8050 gets PP3V3_S5 but PP3V3_S4SW_SNS_FET_R and SMC_SENSOR_PWR_EN are missing
there is alsono short on the line
 
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2informaticos

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SMC_SENSOR_PWR_EN appears on S0 state; your board is stuck in S3, as you told...
PM_SLP_S3_L goes high, or pulse at least?
 

2informaticos

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That means your board is in S0 state.
So all the voltages controlled by PM_SLP_S3_L should appear.
Check "S0 Enables" signals at page 59.
Be sure you get correct PM_SLP_S3_BUF_L first...
 
Pp1v05_sus 1,05
pp1v8_s3 1,80
pp1v5_s0 1.50
pp1v5_s0sz_audio_adh 1,5
pp3v3_sus 3.32
pp3v3_s4 39.6 mili volt
pp3v3_s3 3,28
pp3v3_s0_fet_r 3,28
pch_hsio_pwr_en 2,55
s5_pwr_en 3.4
s4_pwr_en 3.328
usb_pwr_en 3.28
pm_slp_s4_l 3.28
p3v3s3_en 3,28
p1v8s3_en 3,27
ddrreg_en 3,28
 

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"pp3v3_s4 39.6 mili volt"
Is there short, or low value?
Post U8000 voltages; you may need to change it...
 
I've replaced the U8000 and
pin1 PP3V3_S4_FET_R 3.02v
pin2 PP3V3_S5 3.32V
pin3 PP3V3_S4_FET_R 3.02v
pin4 PP3V3_S5 3.32V
pin 6 S4_PWR_EN 3.32

I've replaced the U8050 but nothing's changed I get
pin1/3 PP3V3_S4SW_SNS_FET_R 0.3v
pin 2/4 PP3V3_S5 3.32v
pin 6 SMC_SENSOR_PWR_EN 0

I tried to bypass the SMC Sensor but the charger light changes from amber to green and again amber but the fan doesn't spin.
the fan is known working one and also there is no USB activity.
 
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yes I did. tried to bypass the SMC but the charger light changes from amber to green and again amber but the fan doesn't spin.
the fan is known working one and also there is no USB activity.
 
all of the sudden the light on the charger is gone and System_Onewire is dropped down to 0.8v but SMC_BC_ACOK is present 3.4
SMC_RESET_L is. 3.37
 
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I tried to bypass smc by holding the power key for 10 second and connect the charger ( while keep pressing the power for the next 10 second ).
the board didn't power on but the light on the charger is back
 

2informaticos

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Do you mean these voltages are present and steady?
Check all the voltages involved in ALL_SYS_PWRGD generation...
 
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