Hello, guys
I am trying to repair some motherboards of nintendo switch (mariko) with no power situation. Symptoms are same, no power, black screen, battery charging OK (0,4-0,5A@15V). If i mesure output voltages of MAX77620 PMIC i get all voltages(1v8, 1v1, 0v8) except 1v35 rail. On this rail voltage is 0v after i press power button.
I tried to change MAX77620, MAX77812, BQ24193, but no result - voltage on 1v35 rail is 0v.
I am also tried to change Fuel Gauge IC and sometimes it works, 1v35 rail comes back after replace MAX17050. What else could be the reasons for the lack of voltage 1v35 at the max77620 output? Bad CPU/EMMC (because, as far as i am know, CPU drives this PMIC via I2C bus)?