[SOLVED]820-3115-B PPBUS_G3H up and down

[macfix]

Hello everybody

I m working on 820-3115 not power up PPBUS_G3H voltage is up to 14.4v 2 second later down 4.8V or 5V .

Magsafe green led is ok
PP3V42 is stable
Removed F7040 nothing changed
R7020 voltage is 16.6V and stable
Replaced U7000,Q7030,Q7035 nothing changed
CHGR_UGATE voltage is up and down
When i measured U7000 around resistors all is fine..
Also checked R7020,21 and R7051,52 they are ok
When i injected 12.5V PPBUs_g3h fan spins,

What can i do next step?

 

[dukefawks]

Measure on pins 17/18 and 27/28 of ISL6259, corroded trace in the sense circuits are common.

 

[macfix]

Duke problem fixed after when cable jump to 17/18 line to R7050 ..

Thanks too much again