PreArm Trim Error

Hello Everyone!
My name is Pavel. I’m beginner. I have some difficulties with my Quadcopter and Pixhawk PX4 PIX 2.4.8 Flight Control. On Miission Planner Flight data screen I have message: “PreArm: RC16 maximum is less than trim”
What does in mean?
What should be done to fix it?
Help me, please. Thank You


You can fix this by setting RC16_TRIM to 1500, RC16_MIN to 1000 and RC16_MAX to 2000 in the full parameter list. You will have to do this for any channels above the number of channels your receiver has. This is caused by a mission planner bug in the RC calibration, you also may be able to download the beta mission planner and re-calibrate RC inputs to fix.


Great thanks for such a quick reply. I use version 1.3.62 MP. Which file is Beta?
or ?

in your current version, go into the help tab and at the bottom click check for beta updates

ps: the beta is MissonPlannerBeta


Hi, Peter!
Can I use Mission Planner to configure settings of this PDB

yes, it gives the amps/volt values and voltage scale here:

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Do I need to install ChibiOs when installing the firmware?

its recommend to use ChibiOs yeah

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Сan I change the direction of rotation of the props through MP and how?

no, just swap two wires on the ESC

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One more question. My radio is Taranis QX7. I was able to calibrate the sticks through MP, but I can’t calibrate pots and switches. How can I fix it?

it will calibrate everything its sent, you will have to setup the switches to output to the receiver in the transmitter firmware first.


Hi, Peter!

Your tips were very helpful to me. But now I have new questions. I find answers to some of them, some don’t.

The EKF value is always red in the Mission Planner. On the Internet, I found several links with a recommendation to disable EKF.

For example:

But in those examples, the interface of the previous versions of the program is used, and in my version I did not find the parameters mentioned. What could You recommend to me?
Thank You