Macbook Air 2020 A2179 820-01958 (5V to the USB-C port unstable)

[thuygsm]

Hi everyone,
I have a MacBook Air A2179 in my hands that had power problems (5V to the USB-C port unstable).

I noticed there is liquid at U3200 and U3100 and have replaced them.
PP1V5_UPC_X_LDO_CORE : 1.575V
PP3V3_UPC_X_LDO : 3.280V
PP3V3_G3H_RTC: constantly fluctuating from 0.5V to 3.284V
I have isolated R6979,
Pin 1: 3.280V stable
Pin 2: 0.447 (diode)
PPBUS_G3H: 12.28V (with R6979 isolated)
PPBUS_G3H: fluctuates 5V -> 4V -> 6V -> 12.28V(when R6979 is present), and repeats in a loop
What should I do next?
I hope everyone can help.
Thank you.
https://youtube.com/shorts/VGREJgMyk...4Nw1n1lljUjZI5

[easy boy]

Is it fixed yet? What was the specific problem? I have the same issue.

[mon2]

From the details of the first post, the regulator for PP3V3_G3H_RTC is working due to the isolation test.

Remove all power. Meter in resistance mode. Measure the resistance to ground of PP3V3_G3S which follows the wimpy load switch @ U8210 and is linked to PP3V3_G3H_RTC.



What is the voltage to ground of CHGR_EN_MVR = enable for the above power rail? Is it also toggling on/off?

What is the current draw on the USB-C meter? Same as OP?

reference:
https://repair.wiki/w/MacBook_Air_A2179