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

 

[2informaticos]

First of all, welcome to the forum!

Did you replace U3100/200 with chips removed from same donor board model?
You must also maintain their position...

 

[thuygsm]

Thank you for your reply.
I took it from an iCloud main board A2179 and placed it in the correct position.
Let me ask further, inside them, is there a program? Is it in both or just one of them?
And which device can read it?

 

[2informaticos]

Replace U2890 too, from same board; it helds the firmware required by CD3217 chips.
Anyway, make a backup of the working one (from donor); usually we reflash the chip from the board under repair.
A cheap CH341 programmer is good enough; just need a board adapter to solder the chip on it.

BTW, write directly into reply box, instead of clicking Reply button.

 

[thuygsm]

Tôi không thấy U2890 trên bảng (820-01958).
Đó có phải là SPI ROM U3060 không?
CH341 tôi đính kèm có phải là cái hỗ trợ nó không? Và bạn có thể cho tôi thêm thông tin về bộ chuyển đổi kết nối với CD3217 không?
Tôi có một chiếc RT809H; Tôi không chắc liệu nó có hỗ trợ nó hay không. Nếu có, vui lòng cung cấp cho tôi thêm thông tin về bộ chuyển đổi để kết nối với CD3217.
Cảm ơn bạn.

 

[2informaticos]

???