820-01521 PPBUS short

[drmacbookth]

Hello, I have a Macbook Air Retina with a short on the PPBUS. 0V, 5V on the type c ports, no signs of liquid. Can I safely inject voltage or do I first need to remove all U72xx? When just connecting the charger nothing gets hot. Nothing looks bad as well I visually checked all PPBUS IC's.

 

[2informaticos]

NEVER inject voltage before checking for short on high-side of secondary powrer supply.
Compare short ohm value with all coils in the board first.

 

[drmacbookth]

Ohm values where the same with working board. I removed all CPU Power IC with PPBUS_HS_CPU connected and injected power, C7078 was short and burned hole in the board. After making copper line and replacing it, I have PPBUS restored but one of the charge IC had 5v no amp the other one 0.25A, replaced the one without amp and got the mac working again. Thanks, now the other one