Macbook Air 820-00165 No Power

[WiFiComputers]

I got a Macbook Air , which had liquid damage on U7501 TPS51980 Pin number 9 and 10, I am getting 3.3v on l7520, but 0v on L7560, Missing Enable signal on U7501 at Pin 21
Already Replaced U7501 but same status, not sure what is my next step

 

[aprendiz]

SMC_PM_G2_EN present????

 

[dukefawks]

The basics first. Is PPBUS even present? Orange light?

 

[WiFiComputers]

Yes SMC_PM_G2_EN Enable Present 3.41V and Yes Orange Light and PPBUS_G3H Present 8.58V

 

[aprendiz]

Broken trace or corroded resistor on feedback line for 5V??
Resistance to ground on L7560?

 

[WiFiComputers]

I checked with diode mode, traces looks fine, Resistor to ground is 30k and going up
Resistor to Ground on Pin 4 at U7501 is about 90K

 

[dukefawks]

So 3V3_S5 is present and it is simply not doing the usual 5V_S4.

Could be anything, common suspects are U1900, U1950 corrosion or crap under SMC.