[whitesoxsfan12]

I recently purchased a new quad and CC3D flight controller and have been having some odd issues. I can run the Libre Pilot setup, but the ESCs will only beep but not start rotating. Another issue is that the power coming from the CC3D to the RX is only 3.1v , which isn't enough to power the 4v RX. The flight controller doesn't seem to have any updating/connecting issues with the computer over USB. At this point I'm starting to believe that it's a bad FC as those seem to have a high DOA rate. Any ideas?

Thanks

[Eagle71]

Is the cc3d only powered over USB or over the PDB with the flight accu?

[TheOtherCliff]

The voltage coming out of CC3D is the same as the voltage going in.

The voltage going in usually comes from the ESCs (the BEC inside the ESC) or a BEC on the PDB so I would verify that the ESC is putting out good voltage.

Is anything hot?  That is where to look for excess current draw that can cause this issue.

Do your ESCs have BECs or are they opto?

[jackyoung]

CC3D? It is a Open Source Flight Controller 32 Bits Processor. But it not include BEC, therefore, what's your option BEC? If your BEC can not provide 5v output, maybe cause your issue. For CC3D flight controller, I suggest you select PDB XT60 Power Distribution Board BEC 5V 2A 12V 0.5A with XT60 Plug. Of course, you can choose other flight controller, there are a lot of brands of FC on the market. Highly recommend this article to you: Quadcopter Flight Controller Board Comparison http://www.rcdronegood.com/flight-controller-board-comparison/