Hi all dear friend., today I am working on 820-01521-A logic board (MacBook Air A1932 2019) stuck on 5V .19 milliamps. The history of this logic board was liquid spill on major components. First gave a good cleanup & both CD3215C00Z were getting very hot, so I replaced both. Now on the 12V coil, there is only 5v present & 3.3V is perfect. In some area like PPVIN_G3H_P3V3G3HRTC , PPBUS_G3H_TPAD etc., 12V is perfect. On the 5v coil .2 volts only. I checked the enable signal on the regulator chip, enable is NOT present. The logic board is very clean, I do not see any signs of spill anymore. I checked ohms reading on the 5v coil it just fluctuates between 120K & so on, not a short. Some repair tips will be greatly appreciated. Thanks in advance
-
-
Power delivery is not at 20v so cd3215s must be reviewed. Test each LDO rail on the cd3215s.
https://logi.wiki/index.php/CD3215_Bootup_Sequence
Comment