820-00875 No boot

[DaveDD]

Hi guys! This is my first repair on a 820-00875.
Customer report no power after a small water spill near trackpad.
When I connect usb-c 61w power unit, fan starts and spin at lightspeed. Nothing else happens.
After checking power lines found that PP3V3_S0 is missing (0,6v).
Found some corrosion under U8220, PM_EN_P3V3S0 and PP3V3_S5_S0R are present and stable.
I've tried to clean/resolder U8220 but no success, still 0,6v on PP3v3_S0.
Can u8220 be burned? it looks perfect... I should try to bypass it and inject 3v3 on PP3V3_S0 and see what happens?
Thank you in advance.

 

[2informaticos]

First of all, welcome to the forum!

Check diode mode to ground at 3V3_S0.
If not short, nor low value, then change U8220.

Fan spins high because of trackpad temp sensor issue.

 

[DaveDD]

Thank you man.
Diode mode with red probe to ground is 0.352
I'll try to change U8220 and let you know.

 

[DaveDD]

Changed U8220, now everything looks great!
Machine is in perfect shape. Thank you again...
Now i have to deal with a newer A1932 but i'll post a new thread for that.

 

[2informaticos]

You're welcome, glad to hear is solved...