Hello All:

      When I start DJI GO 4 app on my iPhone 5s, power up controller, then power up Mavic Pro, after a few seconds, I get message about Compass needing to be Calibrated.

      I have tried Recalibrating compass four times.  Once in an open area, where I have previosly and succesffuly recalibrated iPhone, Garmin GPS, and Jeep's builtin compass.  Next two times, I went even further away from any metal buildings or fencing (750-feet away).  Last time I tried, I went another 200-feet away.

    I though compass calibration was resolved on foruth attempt.  When I powered up controller, then powered up Mavic Pro, I did not get message about compass.  However, when I powered up controller, started DJI GO 4 app, then powered up Mavic Pro, once again after a few seconds I got message about Compass needng to be Calibrated.

    From what I have experienced so far, anytime I have quit DJI GO 4 app - On next startup of App, Controller, Mavic Pro, regardless of what is started first, I get message about Compass needing to be Calibrated.  Whereas, if I keep DJI GO 4 app running, power up controller then Mavi Pro, I don't get compass calibration message.

    Anyone else seen this problem?  If so, did you find a solution?

    I am also getting intermittenet message from GO 4 app about some software components needing update (even though it was all updated 16-hours before).  But that will require another Thread and capturing actual message.

Thanks in Advance
HedgeTrimmer

In these situations its best to refresh your FW using Assistant 2, calibrate the IMU on a flat surface then calibrate the compass when outside and away from any ferromagnetic interference - wearing an Apple watch or even a bunch of keys in your pocket can cause this to happen... If it still persists then you may have a faulty drone that needs to be sent back.

A CW Posted at 2018-2-2 12:36
In these situations its best to refresh your FW using Assistant 2, calibrate the IMU on a flat surface then calibrate the compass when outside and away from any ferromagnetic interference - wearing an Apple watch or even a bunch of keys in your pocket can cause this to happen... If it still persists then you may have a faulty drone that needs to be sent back.

Thanks.  When I get someplace where I got a Free internet connection vs. pay by Megabytes I will down load Assistant 2, and give it a whirl.

HedgeTrimmer Posted at 2018-2-3 15:15
Thanks.  When I get someplace where I got a Free internet connection vs. pay by Megabytes I will down load Assistant 2, and give it a whirl.

Refresh the FW and calibrate the IMU at home.

A CW Posted at 2018-2-4 00:30
Refresh the FW and calibrate the IMU at home.

I did refresh the Firmware and calibrate the IMU (twice).

Unfortunately it did not help.

I got Compass Re-calibrate using iPad Air2.  
I did Re-calibrate without problems, and Mavic flew fine.
Stopped flying for short period to review recorded video.
When I went to fly drone, I once again got Compass Re-calibrate.  Re-calibrated and Mavic flew fine.

Today I tried using iPhone 5s.
Once again, I got a Compass Re-calibrate.  Did Re-calibrate, and Mavic flew fine.

Either there is a problem with Mavic or DJI Go4 software running on admittedly older Apple iPad & iPhone.

HedgeTrimmer Posted at 2018-2-11 22:51
I did refresh the Firmware and calibrate the IMU (twice).

Unfortunately it did not help.

That probably isn't a software glitch but more than likely the location you are flying in. You will always get compass errors indoors for example due to the magnetic interference. Try a different location outside and if it persists you may need to send the drone in for checks/repair.

A CW Posted at 2018-2-11 23:37
That probably isn't a software glitch but more than likely the location you are flying in. You will always get compass errors indoors for example due to the magnetic interference. Try a different location outside and if it persists you may need to send the drone in for checks/repair.

It is definitely outside and in two different locations.  With different take-off points in one of outside locations.

Try an IMU calibration too.

A CW Posted at 2018-2-12 10:11
Try an IMU calibration too.

Thanks for reply.  But I already did two IMU calibrations.

My plan is to:
1) Do compass re-calibrate.
2) Briefly fly.
3) Power cycle Mavic Pro
4) See if I get compass re-calibrate.

Repeat steps 1 thru 4, except Power cycle Remote Controller.

Repeat steps 1 thru 4, except quit / restart GO4 App.

If one of those do not cause a Compass Re-calibrate then try combinations.

Let me know how you get on. Hopefully it’ll work or it may be that the compass is defective and needs repairing by DJI.