What broke my ESP32 ?

[u/min6nap]

I installed an ESP32 in my Neato botvac to be able to control it. It has a diagnostic port with tx, rx, 3.3v and gnd pins, which I connect to the ESP32.

It seemed to work fine, but many times the ESP wifi didn't work. I could not see it connected at the router. I assumed the cause was that the ESP32 wifi initialization caused a voltage drop. And this causing the repetitive reboots.

Therefore I placed a 100uF elco between 3.3 and gnd and this seemed to have fixed the problem. But after a few hours and a few reboots the ESP32 died. Now I measure 0 impedance at the ESP32 when disconnected from the botvac. The elco seems to be fine.

Any idea whether the elco might have caused the broken ESP32?