820-00165 water damage

[lincev]

Hello, I have this board with liquid damage and high corrosion U7701, U3210/20 board turned on but without backlight when removing U7701 it does not turn on only green LED and then orange and don't fan speed . I suspect a short but I can't find it.

thanks for all

any values:

PPBUS_G3H: 8,5v
PP3V42_G3H: 3,39
PP5V_S5: 4,98
PP5V_S4RS3: 0v
PP5V_S0: 0v
PP3V3_S5: 3,30v
PP3V3_S4: 0,07v
PP3V3_SUS: 0,70v
PP3V3_S3: 0,45v
PP3V3_S0: 0v
PP1V8_S3: 0v
PP1V2_S3: 0v
PP1V05_SUS: 0v
PP1V5_S0: 0v
PP1V05_S0: 0,15v

 

[2informaticos]

Check PM_DSW_PWRGD, PCH_DSWVRMEN, SMC_ADAPTER_EN, PM_BATLOW_L and the 4 PCH's RTC (DC) signals.

 

[lincev]

PM_DSW_PWRGD=3,38v
PCH_DSWVRMEN=3,11v
SMC_ADAPTER_EN=3,38v
PM_BATLOW_L=3,30v

RTC_RESET_L=3,30v
PCH_SRTCRST_L=3,30v
PCH_INTRUDER_L=3,00v
PCH_INTVRMEN=3,20v

 

[2informaticos]

Check diode mode to ground at 3V3_SUS.
Post U8020 voltages.

 

[lincev]

3v3_SUS value 1010/975 sometimes

U8020

Pin1=3,30v
Pin2= 3,30v
Pin3=3,30v
Pîn4= 3,30v
Pin5=0v
Pin6=0v

 

[2informaticos]

"PP3V3_SUS: 0,70v
----------
Pin1=3,30v
Pin3=3,30v"
???
Please, use schematic names, instead of boardview; avoid any missunderstood.

 

[lincev]

sorry

pin1 PP3V3_SUS_FET_R=3,30v
pin 2 PP3V3_S5= 3,30v
pin 3 PP3V3_SUS_FET_R=3.30v
pin 4 PP3V3_S5= 3,30v
pin 5 GND=0v
pin 6 PP3V3SUS_EN=0v

 

[2informaticos]

Please, check again 3V3_SUS.
You've said first 0.7V and now 3.3V again.
Just in case, change U8020; 3.3V output without enable???

 

[lincev]

hi again, I change u8020

now Is perfect

pin1 PP3V3_SUS_FET_R=3,30v
pin 2 PP3V3_S5= 3,30v
pin 3 PP3V3_SUS_FET_R=3.30v
pin 4 PP3V3_S5= 3,30v
pin 5 GND=0v
pin 6 PP3V3SUS_EN=3,30v

but I don't have spin fan... green led and orange led

 

[2informaticos]

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

 

[lincev]

I think I won't be able to do this test, I don't have an oscilloscope. thanks all the same

 

[2informaticos]

Why will you need an o-scope?
Can't you see the pulse on your voltmeter???

 

[lincev]

Ok, sorry, I didn't understand you correctly, by researching your "how to" help section I was able to learn.

i have 3,38v with pulse to 0,32v

 

[2informaticos]

Check for pulse at PM_SLP_S5_L (at same time).

 

[lincev]

PM_SLP_S5_L= 0v with or without pulse...

 

[2informaticos]

Did you try SMC bypass mode?