After 2 weeks of resetting to default and turning on and off, I had now decided to send my Phantom 4 to Brisbane for repair. Every time i started it , it just wanted IMU calibration which failed every time, i would have done this 20 times.

Then I found a video on the web which suggested putting the drone on its side , them starting. To my amazement the calibration process started and worked.

It is my hypothesis that if the drone has an IMU error, in the upright position, they remain off.

Any other position wakes up the gyroscope and accleromoter as they are not normal, and it wants to calibrate, and works.

I  assume this has saved me hundreds of dollars but i have my trusty P4 back. I hope this helps.


Regards

Tim

Hi, Tim. Thank you for sharing this information with other fellow users. If the Phantom 4 series IMU calibration fails to complete and cannot proceed to the next step after a long period, we suggest other users to do the same thing.  Place the aircraft as shown in the figure below:

Then during calibration, the users must follow the diagram shown on the IMU calibration view to maneuver the aircraft to different altitudes. Thank you for the support and have a nice day!

Can I add to this please.
Was trying to calibrate IMU kept stalling at screen/stage 4 only four or five attempts.
On one occasion for 30 minutes till I had to recharge the battery
Eventually I just turned the drone onto the back corners - with gimbal pointing upwards - it went to 5 - turned it upside down - both unprompted and it went to stage 6 - calibration complete /successful.
It still recognises the drone and flies correctly but not fully tested.
The reason I was calibrating things, compass, gimbal & IMU was it hadn't been done in some time since moving the drone from Birmingham area to Edinburgh AND - when flying level flight just forward with the other stick in neutral - it slowly loses height.
Any comment on this behaviour or other suggestions are welcome.
Thank you.

djiuser_eBDwqADoS22O Posted at 2023-4-4 02:27
Can I add to this please.
Was trying to calibrate IMU kept stalling at screen/stage 4 only four or five attempts.
On one occasion for 30 minutes till I had to recharge the battery

I used the described technique and it worked.  I did have to put the aircraft in several positions to complete the process.  Money saved.  Thanks to all who posted.