I have a MAVIC AIR purchased in Brazil, BR version.
But, almost every time I use it, it asks to calibrate the compass.
Today I did a test that follows in the video.

1) Drone turned on and everything ok
2) I put it on the car and found that the compass indicates interference. Then the App asks to calibrate the compass
3) Remove from the top of the car and place elsewhere without interference. He continues to ask for recalibration.
4) In the same place, I turn it off and on and everything is ok.

Was it not to exit the CALIBRATION information when I removed it from a place with interference?

I have already reinstalled the firmware with DJI Assistant 2 and calibrated the IMU. But without success.

DJI GO 4 4.2.24
Aircraft 01.00.0400

I'm from Brazil

Move to the grass area and try it.

Kingram Posted at 2018-8-18 12:00
Move to the grass area and try it.

the same thing happens.
the problem is that even without interference, it asks to calibrate. Unless you turn it off and then on again.

No you should always turn it off and then move, when it was placed on the car compass heading obviously moved, just moving it while still on compass may not necessarily move back to correct heading.
So always turn off and restart at new safe location.

Yes, don't just move it. Turn it off, move it and then turn it back on. Also make sure you're doing it out away from metal, concrete, etc.

Paul_IA Posted at 2018-8-18 12:54
Yes, don't just move it. Turn it off, move it and then turn it back on. Also make sure you're doing it out away from metal, concrete, etc.

I thought it was just moving. No need to hang up and call again

I've always set my MP on the ground and THEN turn it on.  Last thing I do and then walk away to launch it.  Never had a request to calibrate the compass.

Used to get request from GO-4 for Mavic Pro compass to be calibrated when GO-4 was running on either iPhone 5s or iPad-2(?), at least once every flying day, sometimes every flight.  Didn't matter where, could be 400-feet away from nearest source of magnetic interference.  Got so bad, I would calibrate compass once for day of flying, and ignore any further requests.  

Compass calibration requests stopped when I switched over to using a CrystalSky.  I have no idea as to why.  Only guess that CrystalSky was running earlier version of GO-4 than what was being run via iOS.

HedgeTrimmer Posted at 2018-8-18 13:51
Used to get request from GO-4 for Mavic Pro compass to be calibrated when GO-4 was running on either iPhone 5s or iPad-2(?), at least once every flying day, sometimes every flight.  Didn't matter where, could be 400-feet away from nearest source of magnetic interference.  Got so bad, I would calibrate compass once for day of flying, and ignore any further requests.  

Compass calibration requests stopped when I switched over to using a CrystalSky.  I have no idea as to why.  Only guess that CrystalSky was running earlier version of GO-4 than what was being run via iOS.

I also think the problem is related to DJI GO 4.
For he does not delete the message, even putting it in a place without interference.
I mean, without having to restart the aircraft.

Brad Bilger Posted at 2018-8-18 13:38
I've always set my MP on the ground and THEN turn it on.  Last thing I do and then walk away to launch it.  Never had a request to calibrate the compass.

Mavic Pro or Air? Pro also had no problem.

Paul_IA Posted at 2018-8-18 12:54
Yes, don't just move it. Turn it off, move it and then turn it back on. Also make sure you're doing it out away from metal, concrete, etc.

The only way you can then start the flight with the aircraft in hand.
Because most soils are concrete or asphalt.
If you put the MA on the grass, it will soon wind up your propellers because it is too low.

rodrigosanches Posted at 2018-8-18 14:13
I also think the problem is related to DJI GO 4.
For he does not delete the message, even putting it in a place without interference.
I mean, without having to restart the aircraft.

I don’t think that go4 is the reason, I’ve been using both CS and iOS iPhone 7 with Mavic Pro have never been asked to calibrate.

Understanding what happens when your compass comes in contact with magnetic interference will help you.
If you put your craft in the vicinity of mag interference compass will move, IMU will stay on aircraft heading, if you take off once you clear interference compass will go to correct heading, but IMU which is supposed to move in line with compass heading , will now be confused and move at the same time , so let’s say 5 degrees left for compass IMU will also move 5 degrees left, so you still have conflict with compass and IMU , this is why you need to turn off aircraft move and restart. If you take off with conflict between IMU and compass then you are likely to see IMU heading warning and aircraft go to Atti mode, so the best advice should always be turn off move and restart.

Here’s a link that may help.

https://forum.dji.com/thread-104222-1-1.html

hallmark007 Posted at 2018-8-18 14:29
I don’t think that go4 is the reason, I’ve been using both CS and iOS iPhone 7 with Mavic Pro have never been asked to calibrate.

Understanding what happens when your compass comes in contact with magnetic interference will help you.

Great explanation. In MP also had no problems.
But, I see a lot of people complaining about MA. It could be some recurring problem.

rodrigosanches Posted at 2018-8-18 14:37
Great explanation. In MP also had no problems.
But, I see a lot of people complaining about MA. It could be some recurring problem.

I think that’s a different matter, you induced interference into your Mavic Air , my explanation was regarding this.
With regards to Mavic Air asking some repeatedly to calibrate, yes I know this is a problem for some, I myself have been asked more than I would like to calibrate compass in Mavic Air , however I believe that this may be caused by oversensitive sensor causing some to calibrate more than needed, hopefully this will be sorted in upcoming FW/SW.

But both these things with calibration are seperate, so I was trying to keep them that way.

Good luck..

rodrigosanches Posted at 2018-8-18 14:26
The only way you can then start the flight with the aircraft in hand.
Because most soils are concrete or asphalt.
If you put the MA on the grass, it will soon wind up your propellers because it is too low.

if you put the MA on the grass, it will soon wind up your propellers because it is too low.

You need to:
a) use a take off / landing pad (DJI preferred)
b) Take off from hand and do hand catch upon return
c) Install leg extensions to keep props above grass and weeds

I bought a portable collapsible landing pad similar to one DJI sells, except much bigger in diameter.  Tall grass and long weeds can be blown over edges of smaller pads and catch Props or motor rotors.

I also have leg extensions, but have not used those as of late.

rodrigosanches Posted at 2018-8-18 14:26
The only way you can then start the flight with the aircraft in hand.
Because most soils are concrete or asphalt.
If you put the MA on the grass, it will soon wind up your propellers because it is too low.

Because most soils are concrete or asphalt.

I have never seen asphalt put down with steel mesh or rebar.
Steel mesh or rebar is most commonly used with concrete.  Concrete when used for sidewalks, driveways, roads, boat piers, picnic tables, structual beams and columns, and building floors.

Unless there is metal piping or electrical lines under asphalt, you should be able to fly from asphalt areas without encountering magnetic interference.
You can use a Smart Phone or Smart Tablet to double-check or verify whether there is hidden metal very nearby (even burried) or hidden electrical lines using free or inexpensive Apps that show sources of magnetic interference.   Possible because virtual all Smart phones & tablets have built-in compasses (X,Y,Z, magnetic field sensors - similar to what drones have).

HedgeTrimmer Posted at 2018-8-18 15:00
Because most soils are concrete or asphalt.

I have never seen asphalt put down with steel mesh or rebar.

I also believe in this.
Is that some people told me to lay on the grass and try again.
But I was on a street made of cement. It is not concrete. Surely there were no iron netting down there.

rodrigosanches Posted at 2018-8-18 15:05
I also believe in this.
Is that some people told me to lay on the grass and try again.
But I was on a street made of cement. It is not concrete. Surely there were no iron netting down there.

Concrete refers to Cement mixed with rocks and sand.
Terms concrete and cement are often used interchangeable, even though not technically accurate.

With that said, chances are if you were on a street made of cement, there was steel rebar, wire mesh put in place and concrete (aka cement with rocks and sand mixed together) poured over it.  Although some will pour concrete then push wire mesh (like cattle panes) down into concrete before it starts to harden.

When you get Compass Error try this:
Turn off drone.
Pick drone up.
Hold drone away from you and away from any metal like chain-link fence, metal railing, etc.
Power drone on.
Now look to see if GO-4 App reports Compass Error or magnetic interference.

Most of common sources of magnetic interference will not cause Compass Error when drone is moved more than 1-1/2 feet (or 1/2 meter) away from source.  By holding drone up and away from you, drone should be several feet away from any ground based magnetic interference and anything you might have on you that could cause magnetic interference.

Which leads to several questions:
1) When you are seeing the Compass Error messages, do you by chance have anything on you that could be source of magnetic interference (magnetic bracelet or neck chain, heavy metal wrist watch, large metal belt buckle, large metal pocket knife, etc)
2) Do you have any metal implants from being injured, like steel strips for shattered arm or leg?
3) Do you have a iWatch or similar electronic device that might cause interference with drone's magnetic sensors?

rodrigosanches Posted at 2018-8-18 14:24
Mavic Pro or Air? Pro also had no problem.

MP=Mavic Pro.  Safety procedures for each one will be very close..

rodrigosanches Posted at 2018-8-18 15:05
I also believe in this.
Is that some people told me to lay on the grass and try again.
But I was on a street made of cement. It is not concrete. Surely there were no iron netting down there.

ALL Concrete, as HedgeTrimmer stated, is made of Cement AND Steel.  ALL Concrete, unless put in by some fly by night company or put in by a homeowner MUST have Steel either in Mesh form or Steel Rebar.  
Asphalt is Semi Flexible and will bend and adapt to a changing environment.  Concrete WON'T!  Concrete will have Steel.  Otherwise it won't last more than a year or so.  

Put Mavic on flat surface immediately after turn on. It need stand upright on stable platform when start up. Put it upside down or moving when power up will mess up the IMU and Compass initialisation.

rodrigosanches Posted at 2018-8-18 14:26
The only way you can then start the flight with the aircraft in hand.
Because most soils are concrete or asphalt.
If you put the MA on the grass, it will soon wind up your propellers because it is too low.

Wait, you're trying to calibrate the compass right? Why would the grass wind up your propellers because the propellers shouldn't be running when you calibrate the compass and you should be holding the drone.

I think you're talking about take off and you can do that anywhere you want after the compass is calibrated. All we're saying is do your calibration out away from metal/concrete (like on a baseball field or something).

rodrigosanches Posted at 2018-8-18 15:05
I also believe in this.
Is that some people told me to lay on the grass and try again.
But I was on a street made of cement. It is not concrete. Surely there were no iron netting down there.

“SURELY “is the problem, if you are not sure or don’t know, then move to a more safe location.