Pixhawk4 + Raspberry PI3 power


Tell me please, can I use port Telem1 (or Telem2) also to power RPI3 using pin +5V and GND?

The Pixhawk 4 itself is powered by power management board PM07.

No. Too much current. While it might work periodically it’s not a good idea. It’s way underpowered for that.