Motors not receiving any power/commands, Battery monitor not working, SPM4650 receiver stopped working

Hardware Pixhawk family
1

Hi all,

I’m a beginner in drones, and I recently got a Holybro X650 dev kit with a Pixhawk 6X with a v2a baseboard, and I’ve been setting it up using QGroundControl since I’m on a mac. I’m struggling to finish the build since I’ve encountered issues with the battery, motors, and receivers.

For the battery, I can’t find the option that would allow for the app to monitor the battery voltage. My battery is a Zeee LiPo 6000 mAh 6S with 22.2V, and I charged it as well. The kit comes with both a PM02D and PM02 power module (the PM02D supplies the power to the FC and ESC, I’m guessing the PM02 is extra), and these are the parameters I have set for it currently:

Screenshot 2026-07-08 at 4.14.40 PM
Screenshot 2026-07-08 at 4.14.40 PM786×408 35 KB

Also to note, when I set the power sensor to other and configure the values from there, it doesn’t allow me to calculate the voltage or current values when I plug them in.

For the motors, I have them connected to Main 1-4 with the motors in subsequent order. When I turn on the drone using the battery to test the motors (with the cord still plugged into QGroundControl), they refuse to work and keep beeping until the safety switch is turned off.

And my receiver, which is a SPM4650 Spektrum receiver (binded to a Spektrum DX6e), is plugged into the UART port with the parameters set for it to work and calibrate. I have gotten it to successfully bind to the transmitter, but sometimes when I reboot the drone (with the battery plugged in, not sure if it matters), and the motor LEDs turn on, it then stops working.

Also, though I read online that some ESCs don’t need calibrating, when I try to calibrate my ESC, it stops working after the safety switch is pressed. I’m not sure if this is what is supposed to happen, so if anybody knows and could let me know that would be greatly appreciated.

Here are my parameters and a picture of my wiring, and thanks in advance:

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IMG_15791920×2560 799 KB

Ardupilot1_Jul8.param (29.0 KB)

2

The ArduPilot methodic configurator is available for macOS and will guide you step-by-step in the calibration process.

3

I’m having issues with the battery monitor. No matter what combination of options I select it won’t change it, it says that there is an error whenever I try to set the voltage and current monitor params on the configurator too.

4

Which ArduCopter version? Which AMC version? Which voltage monitor? How is the voltage monitor connected to the FC? What is the exact error message?

5

ArduCopter V4.6.3, I used the latest AMC from the link (found a windows PC to use), I have a PM02D supplying power to the ESC and FC (which im guessing is the voltage monitor), its connected to the FC via POWER1, the error message is that the parameters couldn’t be configured.

6

Is BATT_MONITOR set to 4? It should not, this is a i2c digital voltage monitor.

7

Yea it was already set to 21, which is the digital battery monitor I’m guessing. When I select it and select a sensor* for it though it doesn’t save it.

*correction

8

Weirdly enough the motor connection don’t seem to have a signal wire, as it only have a black and white wire. Does anyone know how the motors are supposed to receive commands from the FC without it?

9

This doesn’t make any sense. What motor connection?

10

The connection from the ESCs in the drone’s arms to the FC is a pair of black and white wires that (I’m assuming) connect to Main 1-4 at the back of the Pixhawk baseboard. It’s how it came with the drone kit, but I’m guessing that there’s more to them than just being positive and ground wires.

11

No, they are simply signal and ground wires to the FC. Still don’t understand your confusion. You have battery power going to the ESC’s also right?

12

I see, and yes I have the power module connected to the PDB and to the FC, and the motors connected to the PDB. I think its likely that the reason I can’t test the motors is because my battery isn’t set up properly. When I try to set the power monitor and sensor, I can’t find an option that works and shows the voltage and current, so my battery health displays as unhealthy even though it’s charged and connected. Also, if anyone with a X650 dev kit could say what the correct power monitor configuration is, that would be greatly appreciated.

13

This still makes no sense. The battery monitor being setup improperly will not prevent the motors from getting battery power from the PDB.

14

Hm, then what should I do? I’ve been trying to figure this out for a while now and I can’t find a solution.

15

Forget about the power monitor for now, the motors need to run. What ESC’s are they and what firmware protocol do they use? AM32, plain old PWM? Are you using Mission Planner’s Motor Test to test the motors (forget about QGC for now)?

16

The ESCs are Tekko32 F4 45A, they run on AM32, I just tested the motors after plugging them to AUX and setting the parameters and they worked, thanks for the help! The battery monitor is also now working which is awesome. One last thing, when I set the drone to arming mode via telemetry, after spinning the motors for a while, the drone goes back into disarmed mode, is this normal? I also can’t control the motors with the transmitter.

17

Turns out, if I don’t put any inputs in while arming the drone, it automatically disarms. Thanks for the help guys! The drone is now finished :smiley:

18

Yes, that is normal, expected and desired. After arm you either takeoff within a few seconds or it will disarm itself automatically.