see my video here...
https://youtu.be/TmEuTScTl1s
i have no 3.3v in Vdd and no 3.3v in ME6211a ic regulator.
i have no 5v at CSC7102c ic regulator.
i have no 5v in pin 1 of CSE7759b sensing ic.
The problem is the 470uf/10v capacitor which disable all the 3.3 and 5 volts start up voltage.
i use uni-t 210e multi-tester to measure the capacitance and found out that the 470uf read as 2 uf or 1.9uf. This is damage or defective. I replaced it with the same value and the sonoff pow r2 is now working.
Malcohm N. Casiño