820-00875-01 5v 20ma, liquid damaged

[tech-fix]

Hi. As the title suggests, i Have a macbook here that had suffered slight liquid damage. It came to me for a new screen as one of the screen flexes is torn, but on opening found slight liquid damage around the charging area and backlight driver area,

im getting PP3V3_G3H_UPC_XA and XB.

it will occasionaly bump up to 30-50ma, briefly go to no 0ma and then carry on asgain.

i have sorted the corrosion out and checked all caps in that area for shorts but found non.

Where else should i be looking next to get to the bottom of this?

Thanks

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[2informaticos]

Do you get PPBUS_G3H and 3V3_G3H?
Check CD3215 LDOs; voltage and diode mode.

Did you test with battery connected?

 

[tech-fix]

PPBUS_G3H 0.38V
3V3_G3H 3.41V

LDO's on both cd3215 read correctly, however they will read correctly for a few seconds, drop lower and then comeback on reading correctly again.
This was tested with and without the battery

 

[2informaticos]

CD3215 chips have 4 LDOs.
Did you check all of them for sure?
1V1 LDO can only come present on the powered port.

Remove F7000 and check C7050 voltage.

 

[tech-fix]

ok so i have removed F7000 and checked voltage at C7050 and getting nothing there.
I have also just checked LDO 1.1 and getting 0v there

 

[2informaticos]

Post all CD3215 LDOs; voltage and diode mode.