At this point I will call these questions instead of issues since this thing is so new to me and I don't know what normal is.

So yesterday I received my new P4P 2.0 and got it ready to fly last evening and everything charged up today. Connected to the iOS DJI Go 4 app today, activated it, and calibrated the IMU.

Took it outside and while the first page that pops up with all the status stuff on it after connecting stated all was OK, but as soon as I tried to fly I noticed these screen keep telling me something to the effect of:

"Warning:In Flight, working compass encounters data exception,please switch to atti mode if craft behave abnormally"

So I then went to the sensor status page and it says to calibrate the compass.

So I did and it said it completed and I was able to see compass status numbers and they were very low on the scale so I took off. I hovered it around a bit. Man this thing is way way quieter than my Mavic Air! But I noticed that when I would punch it up or down quickly, the drone would yaw a bit on its own and this freaked me out so I landed and tried more calibrations of the compass.

I did this about 5 times in 5 different locations around my yard and each time it told me calibration was complete but I kept getting those warnings on the screen and every time I went back to the compass status page, it would tell me to recalibrate the compass.

Is the P4P 2.0 that sensitive to compass calibrations?

If I find a flat field with nothing around for a few hundred yards will that help?

Any tips to calibrate the compass differently than what I do with the Mavic Air?

Where are you launching from? What sort of surface?

Geebax Posted at 2018-5-31 17:08
Where are you launching from? What sort of surface?

I have tried gravel, grass and moved around as well.

I built the house and know where all the lines are, water line is PVC and the electrical is overhead away from launch point.

Brantel Posted at 2018-5-31 17:11
I have tried gravel, grass and moved around as well.

I built the house and know where all the lines are, water line is PVC and the electrical is overhead away from launch point.

Forget about electrical cables, a compass issue is usually due to launching from a surface that has steel or iron in it. The most common mistake is to launch from a concrete surface that has rebar in it, or from the roof of a car, or from garden furniture with steel frame etc. The best place is from grass that has no buried pipes under it.

Repeatedly calibrating the compass will not do anything, the aircraft is telling you that once it got in the air, the magnetic field is different to what it was when you switched it one. And that is another thing, do not switch the aircraft on while sitting on a metal surface, then take it out and put it on grass. The aircraft takes compass measurements where it is powered up, and if there is metal around, you will get the problem you describe.

Calibrating the compass is probably the most misunderstood part of Phantom flying.
Calibrating the compass does not "fix" problems and the compass should not require calibration under normal circumstances.

calibrating the compass gives the flight controller the data it needs to tell what magnetic influences detected by the compass are part of the Phantom and can be ignored.
That gets done in the factory and you don't need to do it again.
Doing it again doesn't fix anything.

The flight you describe sounds like a properly working compass was warning you of a problem it detected, possibly due to launching from a location close to a lot of steel. (was it on a reinforced concrete surface?)

What is the warning you see on the Compass status page?
Can you post a screenshot?

Geebax Posted at 2018-5-31 17:21
Forget about electrical cables, a compass issue is usually due to launching from a surface that has steel or iron in it. The most common mistake is to launch from a concrete surface that has rebar in it, or from the roof of a car, or from garden furniture with steel frame etc. The best place is from grass that has no buried pip[es under it.

You just described where I took off from.  No concrete, no rebar, no buried steel pipes.

Brantel Posted at 2018-5-31 17:24
You just described where I took off from.  No concrete, no rebar, no buried steel pipes.

See my highlighted comment in reply #4.

Geebax Posted at 2018-5-31 17:27
See my highlighted comment in reply #4.

I never do this.  Never with my Mavic Air and this flight was no different.  I sat it on the ground (gravel driveway) and fired it up.

I am headed to a large open field to try it again.

Geebax Posted at 2018-5-31 17:21
Forget about electrical cables, a compass issue is usually due to launching from a surface that has steel or iron in it. The most common mistake is to launch from a concrete surface that has rebar in it, or from the roof of a car, or from garden furniture with steel frame etc. The best place is from grass that has no buried pipes under it.

Repeatedly calibrating the compass will not do anything, the aircraft is telling you that once it got in the air, the magnetic field is different to what it was when you switched it one. And that is another thing, do not switch the aircraft on while sitting on a metal surface, then take it out and put it on grass. The aircraft takes compass measurements where it is powered up, and if there is metal around, you will get the problem you describe.

every time I went back to the compass status page, it would tell me to recalibrate the compass.
On the compass data page in the app settings, the blue Calibrate Compass is not a warning.
It's a button you click if compass calibration is ever needed (and it's almost never needed).

Labroides Posted at 2018-5-31 17:24
Calibrating the compass is probably the most misunderstood part of Phantom flying.
Calibrating the compass does not "fix" problems and the compass should not require calibration under normal circumstances.

I did not take any screenshots of my actual flight but I duplicated the stuff I was seeing without flying.

Here is the status screen prior to flight (or what I saw prior to my first flight with this drone) notice it says everything is fine.



Here is the screen message that I got multiple times during a very short hovering flight and on the ground immediately after several successful re-calibrations that appeared successful:



And here is what the compass sensor status page shows.  Flashing red calibrate the compass:


Only one time did a re-calibration result in the normal compass interference numbers showing up on this screen like I normally see on my Mavic Air (it only has 1 compass).  When they did show up, the numbers were very low on the left side.  The bar graph was barely visible and it was green.

Notice the warning on this screens says something about abnormal compass direction.  When I look at the radar on the screen, it agrees with where the drone is pointed and approximately where North is.

Brantel Posted at 2018-5-31 17:46
I did not take any screenshots of my actual flight but I duplicated the stuff I was seeing without flying.

Here is the status screen prior to flight (or what I saw prior to my first flight with this drone) notice it says everything is fine.

Notice the remark:  Move away from the magnetic interference.
That is always the correct action when the compass warns of magnetic interference.
If the problem is that your compass is close to steel, calibrating it will not fix anything.
If the indication remains the same regardless of location, that points to your compasses being disconnected.  This is less likely with a dual compass machine.

Labroides Posted at 2018-5-31 17:52
Notice the remark:  Move away from the magnetic interference.
That is always the correct action when the compass warns of magnetic interference.
If the problem is that your compass is close to steel, calibrating it will not fix anything.

So I went out to a field in the middle of nowhere with nothing but grass and I was 200ft away from my vehicle and recalibrated it again.

Same same same.  No better.

This puppy is going back to Best Buy tomorrow.

Compass redundancy switch means the values received from the first compass and the second compass do not match, I have seen this before and if i rem right a refresh of the firmware was advised by support, but do it using the the DJI Assistant and the version downloaded from the P4P V2 page HERE

I am not sure why you calibrated the IMU but it was totally unnecessary. There is no reason to calibrate anything unless you get a message to do so or there is a flight problem.
I suspect you either have a faulty compass or GPS, both of which can give that message.
When you get a replacement, just fly it first and then determine if any calibrations are necessary from any warnings.

Jenee 2 Posted at 2018-5-31 20:23
I am not sure why you calibrated the IMU but it was totally unnecessary. There is no reason to calibrate anything unless you get a message to do so or there is a flight problem.
I suspect you either have a faulty compass or GPS, both of which can give that message.
When you get a replacement, just fly it first and then determine if any calibrations are necessary from any warnings.

Likely but its the first thing support ask you to do is reset defaults and re-calibrate everything.

Bashy Posted at 2018-5-31 19:50
Compass redundancy switch means the values received from the first compass and the second compass do not match, I have seen this before and if i rem right a refresh of the firmware was advised by support, but do it using the the DJI Assistant and the version downloaded from the P4P V2 page HERE

Based on your post I tried that.  DJI Assistant for Phantom 2.0 will not load the current firmware.  It just says "Cannot Load Firmware List, Please Retry"

Ah OK. This is a differentrading issue , probably best to do a new post for it but I'm sure that's your issue though.....

Brantel Posted at 2018-5-31 18:26
So I went out to a field in the middle of nowhere with nothing but grass and I was 200ft away from my vehicle and recalibrated it again.

Same same same.  No better.

Ha, ha - I just had to laugh. Not about you, sorry for issue.

But I was reading somewhere recently - I think it was at Phantompilots - that this guy went out in a field, far away from all possible interference, and:

He got entirely naked!
He insisted that was the right way of doing a compass calibration!  

Imagine he gets caught by police doing the compass dance that way. They gonna lock that Psycho up for good!

Thanks Guys, the drone was swapped out today (a USA based DJI support manager suggested it get swapped that it was likely defective) at Best Buy (no questions asked since it was brand new) and the new one is awaiting being fired up. I will let you know how it goes. This time I am just going to pull it out and get a good GPS lock and fly the sucker without any calibrations.

New drone here and flying.  Bad news is that it does something very similar.  Here are my notification logs:
https://app.airdata.com/main?fli ... ENERALNotifications

At this point I think this is some sort of bug that is not a real problem.  The drone appears to fly fine.  I am headed to another location just to be consistent.

This time I pulled it out of the box and went outside and flew it.  No calibrations whatsoever.

Since this thing appears to have new guts vs the P4P, is there a chance this is just a bug since it has done the same on 2 different drones?

Brantel Posted at 2018-6-1 15:08
New drone here and flying.  Bad news is that it does something very similar.  Here are my notification logs:
https://app.airdata.com/main?flight=7f793e10273cca25520d91237d2953a4&page_id=GENERALNotifications

Where did you launch from?
How far was it from your car or any other steel objects?

Labroides Posted at 2018-6-1 16:10
Where did you launch from?
How far was it from your car or any other steel objects?

The gravel driveway.  Same place I have launched several other drones at least a 100 times with no problems.  Car at least 30' away.

These things can't be that picky or nobody would ever be able to use them.

Latest flight from another location.  This location is in the middle of a fairground field.  Nothing within 100' or more in either direction.

Another longer flight with much more zipping and zagging around.

https://app.airdata.com/main?fli ... ENERALNotifications

Same same on the compass warnings.

Drone flys like a dream!  I am almost convinced this is some sort of app or notification bug that is not real.  

Brantel Posted at 2018-6-1 16:16
Latest flight from another location.  This location is in the middle of a fairground field.  Nothing within 100' or more in either direction.

Another longer flight with much more zipping and zagging around.

I suspect you have a stuck compass. Can you provide a screen shot of the compass values in the DJI Go app?

Brantel Posted at 2018-6-1 16:16
Latest flight from another location.  This location is in the middle of a fairground field.  Nothing within 100' or more in either direction.

Another longer flight with much more zipping and zagging around.

These things aren't all that picky.
I have two and the only time they show a compass error it's because I put the Phantom down on something steel or reinforced concrete.
Airdata only gives a brief summary with no detail.
It would be more useful to see what the actual recorded data shows.
Go to http://www.phantomhelp.com/LogViewer/Upload/
Follow the instructions there to upload your flight record from your phone or tablet.
Come back and post a link to the report it gives you.

Geebax Posted at 2018-6-1 16:35
I suspect you have a stuck compass. Can you provide a screen shot of the compass values in the DJI Go app?

2 drones from 2 different places that are brand new?  The odds on that?  

The compass status page stays locked on this display:



Only got numbers when I first pulled it out of the box and turned it on.  No numbers since, just this screen.  Same thing happened to the other drone.

This is why I suspect this is not a real problem.

Labroides Posted at 2018-6-1 16:37
These things aren't all that picky.
I have two and the only time they show a compass error it's because I put the Phantom down on something steel or reinforced concrete.
Airdata only gives a brief summary with no detail.

That's why I suspect this is not a real problem, just a bug in the notifications.  2 drones out of the box flown in known good areas.  I don't buy it.

I will pull the logs and post.  Familiar with that process.

See I thought I was having a compass issue too with the V2... I am using Android and the latest app but apparently after talking to DJI and a few people it is just a generic message that means nothing and obviously you can't plug in the compass on the Phantoms anyway... the Drone flies fine and will calibrate by way of using the lights for confirmation that everything is a-okay.... apparently you can see the values on iOS but Android for some reason I do not see my compass values. So it is some kind of bug with Android. dji has acknowledged this and they need to put out an update especially for Android users

Brantel Posted at 2018-6-1 16:52
2 drones from 2 different places that are brand new?  The odds on that?  

The compass status page stays locked on this display:

Are you using Android because I have the same problem and I cannot see my values.... the aircraft flies beautifully so it seems just like my problem

Labroides Posted at 2018-6-1 16:37
These things aren't all that picky.
I have two and the only time they show a compass error it's because I put the Phantom down on something steel or reinforced concrete.
Airdata only gives a brief summary with no detail.

Here are the TXT flight logs for the last 2 flights:

This one was a shakedown run...
http://www.phantomhelp.com/LogViewer/3740Z0CLYIXPYQWCJFL4/

This one was a high hover taking pics of a sunset:
http://www.phantomhelp.com/LogViewer/T4XSQX5DOGRIPNQ4ACEW/

Here are the DAT files for the same 2 flights:
https://drive.google.com/open?id ... WQelJScC4PZp7TIHUml

https://drive.google.com/open?id ... kKOBM10yXbpkwC41WC2

Brantel Posted at 2018-6-1 16:53
That's why I suspect this is not a real problem, just a bug in the notifications.  2 drones out of the box flown in known good areas.  I don't buy it.

I will pull the logs and post.  Familiar with that process.

I am not convinced it is a bug. Where is the aircraft when you took that screen shot, indoors? The important thing that is not mentioned in the manual or anywhere else, is that when you power up the aircraft, that is when it initialises the compasses.

Some will start the aircraft in the house, take it out, put it on the grass and if you ask them where it launched from, they will quite honestly say 'from grass'. But they dont make the connection that it was on a metal table in the house when they first switched it on.

And that screen, as Labroides pointed out, is confusing. It is not telling you to calibrate the compass, it is actually telling you to move away from a source of magnetic interference. What is is also NOT telling you is that you should not only move away from that source, but also shut the aircraft off and start it up again once you have moved away.

As time goes by, I am becoming more and more convinced that this issue is the greatest cause of fly away incidents.

Jimmy hoffa Posted at 2018-6-1 17:08
Are you using Android because I have the same problem and I cannot see my values.... the aircraft flies beautifully so it seems just like my problem

No, iOS and I can't see mine either.....

Geebax Posted at 2018-6-1 17:09
I am not convinced it is a bug. Where is the aircraft when you took that screen shot, indoors? The important thing that is not mentioned in the manual or anywhere else, is that when you power up the aircraft, that is when it initialises the compasses.

Some will start the aircraft in the house, take it out, put it on the grass and if you ask them where it launched from, they will quite honestly say 'from grass'. But they forget that it was on a metal table in the house when they first switched it on.

I def think its a bug....well for me atleast and not seeing values. M.singer and a few other guys I had confirmed whether that they saw this screen or not on iOS everything is fine.... on Android same screen

Edit nevermind read the top post you are iOS... definitely weird and maybe not the same as my issue

Geebax Posted at 2018-6-1 17:09
I am not convinced it is a bug. Where is the aircraft when you took that screen shot, indoors? The important thing that is not mentioned in the manual or anywhere else, is that when you power up the aircraft, that is when it initialises the compasses.

Some will start the aircraft in the house, take it out, put it on the grass and if you ask them where it launched from, they will quite honestly say 'from grass'. But they dont make the connection that it was on a metal table in the house when they first switched it on.

Normally I would agree with everything you have said.

I took that image in the house just to get a screen shot.

I never start my drone inside or anywhere else and then carry it to the launch point.  I always start it from wherever it launches.

I see there is another poster now that has a similar issue only he uses Android.  His display is different obviously but basically the same thing.  Now that is 3 of the same drone doing basically the same thing.

Brantel Posted at 2018-6-1 17:10
No, iOS and I can't see mine either.....

Yeah yours is a little bit different message than I have. I had one guy try out iOS and then Android back to back and he said Android was fudged .... same message I got the crazy part is I have told DJI and have done about 35 flights all is well I just wish I could see my compass values

Jimmy hoffa Posted at 2018-6-1 17:13
Edit nevermind read the top post you are iOS... definitely weird and maybe not the same as my issue

Looks basically the same with minor differences due to different OS's.

Brantel Posted at 2018-6-1 17:08
Here are the TXT flight logs for the last 2 flights:

This one was a shakedown run...

Both flights have the same error message:

In Flight, working compass encounters data exception,please switch to atti mode if craft behave abnormally
That is why I don't think it is a bug, the aircraft abviously thinks it has a problem.

Jimmy hoffa Posted at 2018-6-1 17:14
Yeah yours is a little bit different message than I have. I had one guy try out iOS and then Android back to back and he said Android was fudged .... same message I got the crazy part is I have told DJI and have done about 35 flights all is well I just wish I could see my compass values

Notice mine also says abnormal compass direction (and more words that may be masked out due to poor formatting) even though the drone flys well and the radar chart on the app agrees with the controller and where North really is.