Does this look like I screwed up changing a motor/arm?

g1ant · May 13, 2021

I changed out the rear right arm/motor on my Mavic pro as it was damaged by a previous owner. The drone flew ok before this but it was hard to get the prop on.

I took it for a very short test flight. Took off and then moved it forward so it was over grass. After hovering for a few minutes it started to drift so I initiated an auto land. That caused the drone to circle and auto land failed to bring the drone back. So I forced landed it.

Then I couldn't see it in the grass so I did an auto take off. Then got cocky and decided to try and turn it round and fly it home. All was well for a minute or so until it looped and crashed nicely into a small tree.

I notice in the log that there is an wireless interference warning . Is this the problem or do I have an intermittent fault on the new motor?
If one motor fails or slows does this show up as a fault in the log?

Thanks
Alex - Electronics hobbyist and drone Noobie

sar104 · May 13, 2021

The flight behavior sounds like a compass problem. Did you recalibrate the compass after the repair? And did you ensure that the wires carrying the motor current are positioned exactly as before?

g1ant · May 13, 2021

The wires are exactly as they should be I think. . Of course I forgot to recalibrate the compass. I’ll do that then double check the wires and try another flight in a different location.

GFields · May 14, 2021

Keep us updated please

keat63 · May 14, 2021

I've been looking to see how to calibrate the compass, and my app just says that the compass is normal.
I found online that flicking between normal and sport mode in quick succession about 5 times instages a calibration.

Appologies if you knew this already.