820-3332 Green light, Partial PP3V3_S5


New member
Trying to diagnose a rush repair 820-3332 board that was liquid damaged near the top edges of the board. After UC I do have a green light on the charger but no fan spin (SMC Reset is recognized). I have many missing power rails but I do have PP3V3S5_EN on U7201 with a full 3.3v. On other areas of the board, PP3V3_S5 has less than 3.3v (1.7 to be exact) and the board heats up under right under U1000 with the charger plugged in. This leads me to believe there is a short or partial short on this power line but because of how large it is, im having a hard time narrowing down where to look. Suggestions? or am I completely wrong in my diagnosis of PP3v3_s5 being the problem.


I would say a high side FET is shorted. Measure resistance to GND on PPBUS. This will probably turn out to be a dead CPU