Hi guys, working on 820-3662A logic board. Green orange light is on when charger plugged in but no power. PP5V_S4 missing. Checked P5VS4_EN and its missing. It comes from u8170 S4_PWR_en where pin 2- PM_SLP_S5_L is 0V. A little bit strange as P5VS4_EN= 0.07V but S4 PWR EN= 0V. Where does the 0.07V comes from? Chip U7501 itself ? Any help?