820-3115 No green light

[javier_herart]

Hello.
I have this 820-3115-A.
Initially turns on for 3 seconds and then off. Had a lot of liquid damage around and under U1800. I protected U1800, added flux and reflowed the area and cleaned with ultrasonic cleaner.

Then the board had the same issue and I noticed that U7000 was getting a little hot (noticed it with thermal camera) so I replaced it, after that PP3V42_G3H went to 4V so replaced R7021 and R7022 and PP3V42_G3H is ok again but no green light and no attempt to turn on, just takes 37mA.

I reflowed the SMC and no change.

Any suggestion?


Thanks!!

 

[2informaticos]

What is the exact PPBUS_G3H voltage?
Do you get 3V3_S5/SUS?

 

[javier_herart]

SMC_ADAPTER_EN: 4mV
PM_DSW_PWRGD: 40mV
PCH_DSWVRMEN: 3.22V
PM_BATLOW_L: 40mV
PCH_SRTCRST_L: 3.33V
PPVRTC_G3H: 3.34V
RTC_RESET_L: 3.34V


Thanks

 

[2informaticos]

Looks like SMC issue.
Reball it first; if still the same, change SMC.

 

[javier_herart]

Ok, I will do it.

Can I replace the SMC of a 820-3115-A with the SMC of a 820-3115-B?

 

[javier_herart]

Reballing on the SMC worked but I have initial issue. Now I have green light, turns on, takes 231mA and then off.

 

[2informaticos]

Which voltages appear?
Do you get VCORE?
PLT_RESET_L comes high?

Try to start in SMC bypass mode.