No update but when P4 hovers about 60 feet it does these 360 s small circles about 6 feet wide.Also when return to home with auto land it is way off suddenly,Anyone know what has happened.

To me, the most obvious answer is that you need to do a compass calibration.  Also, try flying someone away from where you are seeing this problem.  It really does sound like a compass issue, either you seriously need to calibrate or your might be flying in an area where there is a lot of ferrous metal nearby.

Does it give a calibrate compass warning ?

Maybe it was too dark for visual positioning and it had to rely on GPS?

Sounds more like there was some iron in the ground near where you took off.

If it continues to do it during the day when taking off from different locations, give the IMU and compass a calibration.  You could also check the downward visual sensors - are the sensors clean?  Maybe do a visual calibration in DJI Assistant.

You might also consider an RC calibration, which takes about one minute to do.

Edit:- Or the full Monty...

(The full monty (or the full Monty) is a British slang phrase of uncertain origin. It is generally used to mean "everything which is necessary, appropriate or possible; 'the works'".)



There are five calibrations on the P4:-

1) Sensors (Using DJI Assistant 2 v1.1.2-2, latest version), usually done just after update on Assistant 2.
2) IMU (level surface, make sure it's had time to cool down if it's been powered up, say half an hour at lowest ambient temperature, a cool evening or air conditioned room below 10 degrees C helps).  
Using the newer '3D' IMU calibration routine, my last two IMU calibrations have been done at about 20C ambient air temperature. The subsequent IMU warm up time when aircraft is first powered up and initialising does not seem to have been adversley affected, and warm up time is a few seconds at most.
3) Gimbal (just after IMU).
4) RC sticks (with aircraft off).
5) And compass (in an open area (not over steel reinforced concrete), away from ferrous materials or electromagnetic interference). Get one good calibration, and that should be all that is needed until informed by system or erratic flying that needs investigation. Note that any ferrous metals very close to legs (steel frame in desk, cutlery in kitchen drawer, windowsill strengthening etc) will generate a 'compass error', this does not mean compass needs recalibration. just move the aircraft away from source of interference.

Aardvark Posted at 2017-8-21 08:53
You might also consider an RC calibration, which takes about one minute to do.

Edit:- Or the full Monty...

Thank you everyone i will do the above when time allows me and report back here with my findings,Now off the the Total Luner Eclipse here in the USA.

Have you been messing with your compass?
Has this just started or has it been happening for some time?

What you describe is known as toilet bowl effect and is due to a compass calibration issue.
Perhaps you've recalibrated your compass in a bad location (close to a car or on reinforced concrete maybe?)

If you get a good compass calibration in a magnetically clean area, it should solve the issue.
After that, don't mess with your compass again.

Please change to another location and calibrate compass to see if it works.  

because recently I got confused when my girl texts me and said "HMU" I know that is an Acronym but I did not its meaning. So, I posted that what does HMU stand for and literally 4 to 6 hours I got the answer on DJI.  thanks for all help <3

thanks for helping