I’m a newbie. I just finished building my own quadcopter. I used SP Racing F3 FC and flashing betaflight.
When I tried to arm the quad, I couldn’t when only the battery was powering the module. However, when the quad is connected to the PC via a USB cable, and if I entered motor test mode, I could arm the vehicle.
Then I noticed that when only the battery powers the quad, only the blue LED (the power LED) of the FC is ON. The red LED (the status LED) doesn’t blink at all. It only blinks when I connect the FC to the PC.
I disconnected the FC from the PC, measured if the FC gets 5v from the PDB, and I found it gets the 5v.
What can be the problem?