APM 2.5 Flight Controller Board Not Arming to spin motors


I need help to arm my APM 2.5 flight controller board so as to spin the motors

Presentation of Problem:

I have a Hexacopter and using APM 2.5 Ardupilot board. I have done all the mandatory hardware settings using Mission Planner software; selected frame type, calibrated accelerometer,set compass,calibrated radio, cablirated ESC manually using the DX8 Transmitter and selected the correct flight modes(Stabilize,Acro,Alt-hold and loiter).

Also bound my DX8 transmitter to the RC transmitter

Everything seem to be in order except that nothing works when I connect the Lipo battery. The motors do not spin or roll and all I get is just a disturbing sound and the motors attempting to roll but would not.

On the mission planner, I could see “GPS not fix” so I disabled all the pre-arm conditions just to at atleast make the motor spin still, nothing works.

I attempted to calibrate ESC on Mission Planner but it gave me “set parameters error… ensure your version is AC3.3+” (what does this mean as I already load a firmware version of 3.3 using mission planner.

I really need help to get the stuff up and running and will appreciate any detailed procedures and troubleshooting tips including parameters that I may be missing out.


It sounds like your speed controllers are not calibrated, try your ESCs one at a time in your receiver and try again. Something like this

When you are testing don’t have any props on.

These board come with a test firmware on them and need to be flashed with the latest version using Mission Planner. APM board can only use 3.2.1 as this is the last new version that they can run on this old hardware design.

There is also a message tab on the HUD display that will show what it is doing.


As iseries says the latest version of software you can load on any APM is 3.2.1, so you can not use the ESC calibrate because it requires a minimum of 3.3.3. APM does not have the processing power nor the memory to use any firmware later than 3.2.1. You must calibrate your ESC’s manually. Look in the wiki and it tells you how to calibrate your ESC’s via the all at once method.

The GPS no fix message just means it has not had time to lock onto the satellites. Just take it outside with a clear view of the sky and wait unti it changes to GPS 3D fix.

There are lots of failsafes, turning off failsafes on the advanced page is not enough.