Pixhawk LED is solid red after reflashing


I followed the instructions for building APM for Pixhawk:
dev.ardupilot.com/wiki/building- … ke-on-mac/

and uploaded the new firmware:
make px4-v2-upload

but now the Pixhawk has a solid red LED. I’m wondering where the log is located so I can try to work out what’s wrong. Can you point me to the log please, or suggest what I need to look for?


I still don’t know what solid red means, but I’m guessing it’s not good. Anyway, I think I’ve moved forward with re-flashing ArduCopter on Pixhawk (see my other self-answered question today).

Hello DarylWM,

Yes, the solid red led is not listed on the led behavior, copter.ardupilot.com/wiki/common … wkPX4_LEDs

I don’t know if there is a code that includes the solid red led, but going with the pre-compiled version that can be downloaded from Mission Planner or APM Planner, shouldn’t show the red led behavior.

solid red LED is something you’ll see when there’s a problem with microSD or it’s filesystem.

Did anyone get this solved?
Whilst the Pixhawk may not be programmed to do it, I came across another instance of a solid red main LED with musical tones.

Does anyone know the solution?

I can’t attach the video here, but there is video of the issue at DIYDrones - diydrones.com/group/pixhawk

I have the exact same issue. It was working correctly before I started to hook up my Futaba receiver today. The swith LED does not come on now, and I have the exact startup sounds as you do, ending in a solid red LED. I read elsewhere that those last two tones indicate a hardware failure. I suspect what is happening is that I inadvertently connected the RC/IN cable upside down, perhaps all the output cables upside down as well. Oops.

Yes, I can confirm that I reversed the output cables and RC/IN and connected them “upside down” which likely bricked my PixHawk. By the way, the output pinout orientation is reversed between the APM 2.6 and the PixHawk, therefore my confusion (Signal towards bottom in PX4, top in APM). Upon close inspection however, they are clearly labeled and documented accordingly. Just reversed.

Measure twice cut once works just as well in electronics.
I double check every connection and reconnection when I am working on my gear.

Yep bummer. But I did check twice, specifically to ensure they were connected in the same orientation when upgrading my APM to the PX4. I just checked in the wrong place! But like you, I had never previously made a mistake ever in wiring. Ever. Until now :wink:

Solid [color=#FF0000]Red [/color]I found out means the microSD card contains a large log file.

Usually log files stored are around 20kb big. However sometimes, the .bin log file can go up to +135MB.

So I just delete all folders in the microSD card, and re-insert it back into the Pixhawk. Works fine.

I think it’s some sort of firmware bug that is generating those large .bin log files sometimes.

It occurs with USB and Telemetry.