Hi guys, I have an issue with my drone. I had a minor crash and the battery knocked the condenser, I straighten it, it’s still connected well. I tried to fly it again, the drone dropped down from the sky after one minute of flying just fine. Recently I tried to get it to work and after flying three batteries with no issues take off to landing I can’t get final beeps out of the ESC and the goggles don’t see drone’s battery voltage. What can I do to attempt to fix it?

Plug a USB cable into the FC and then connect a LiPo with the USB cable still plugged in to see if you then get the last 2 beeps. If you do then it means that the 5V regulator on the FC has fried itself and you have one of the following options to rectify the issue:

1. Locate and replace the 5V regulator component on the FC (requires good soldering equipment and soldering skills).
   
2. Inject 5V into the FC via one of the 5V pads using an external 5V BEC.
   
3. Replace the FC with a new one.
   

Yeah I don’t get those two beeps even with the help of usb cable. I also can’t get it connect to the configurator :/

I wonder if I should swap the FC from my other drone, which would be somewhat easy. But I’m worried that if something got fired once this build cannot be trusted. I fly over water for work a lot.

In that case it will either be the 3.3V regulator which has fried (which powers the MCU), or the MCU itself is dead. Either will prevent you connecting Betaflight Configurator to the FC Plug in a USB cable and put your finger on top of the MCU chip to see if it starts getting really hot. If yes then it's very likely dead. If not then suspect dead 3.3V regulator on the FC.