Small story: Bought mavic air from ebay for cheap, as spares or repair. The guy had told me he had found this drone in the park walking his dog. When I received it, I had asked in this forum if it is possible to power it from PSU. And it was possible, so I did it. The only thing I got was solid greenish-yellow light in black and nothing else. Fan is not working at all, the unit heats up, not a lot though, front LEDs are not working as well. Inside there are red stickers that indicate water damage (guess rain, so shouldn't be too bad), but nothing much had corroded and I cleaned it, event by removing all metal heat sinks. After putting it all back together, I get same yellow light. I had found one same case and no more about this same issue, and turns out his main CPU was choked and died. Could that be same for me? Also, maybe this drone doesn't like PSU, so I bought a legit battery but I am still waiting for it to arrive to test this. Maybe someone can help about this issue? Only option could be to replace main board? Also there is no response from USB directly from aircraft.