Hello!
After sending in my Phantom 3 Advanced for inspection at DJI's US service center in California, it was repaired under warranty and shipped back to me. The repair "quote" (even though it was repaired under warranty) indicated it had the "Phantom 3 main control board component" replaced.

I received the Phantom back, performed all necessary firmware checks and calibrations (as indicated by DJI's technical support), and unfortunately I still have the same issue: the "Compass Error. Exit P-GPS Mode" warning message comes up repeatedly in every flight, and the Phantom tends to slightly deviate (mostly to the left) when commanding it to fly straight, regardless of the calibration or flying location. Same as before I sent it in the first time, I've carried out several compass calibrations in open fields, away from any metal or magnetic sources, with nothing metal on me (except the zipper in my pants...), more than 10 ft. away from the RC, several IMU calibrations, etc, and the results are still the same. I've even traveled to another state, re-calibrated, tried flying in an open beach, and still: the "Compass Error. Exit P-GPS Mode" warning message comes up repeatedly in every flight, and the Phantom tends to slightly deviate (mostly to the left) when commanding it to fly straight, regardless of the calibration or flying location.

So before going through the hassle of sending the bird back for repair again or requesting a replacement unit, and seeing multiple threads reporting similar issues, I'd like to ask other Phantom 3 Advanced pilots: Has anyone flown without ever (or at least regularly) seeing compass error messages?


Thanks in advance for the feedback!

SKYER

  

“Fly your drone as though you were flying in it yourself…”

  

See aerial short films at my YouTube Channel: https://www.youtube.com/channel/UC304REG4t2_OWJmQDHLvQ2w  

I fly a lot and the only times I've seen compass errors is if I purposely place the Phantom on something steel like a car roof or reinforced concrete.
I get the impression that most flyers are in a similar situation.

Sadly, you will need to remove your pants before performing the next calibration.

Seriously, are you able to complete the calibration successfully? If so could there be some iron or power line in the ground at your takeoff point?
Else, Call DJI for guidance.

labroides@yahoo Posted at 2016-10-29 20:50
I fly a lot and the only times I've seen compass errors is if I purposely place the Phantom on somet ...

Thanks labroides! That is my impression as well (that most P3A users don't see compass errors regularly), but wanted to validate it by asking the open question here.

Rnfaust Posted at 2016-10-29 20:53
Sadly, you will need to remove your pants before performing the next calibration.

Seriously, are yo ...

Thanks Rnfaust. As mentioned in the original post, I've carried out the calibrations in locations that have no magnetic sources nearby, including power lines or other underground structures.

The calibrations are successful (per the DJI GO status indication), the compass Mod levels shown in the DJI GO app are usually around 1500, and the bird flies ok, except that after flying forward or turning at some point the compass error comes up, and the flight mode switches to "Atti Mode". Normally it regains GPS lock after a couple of seconds and flies ok for a few minutes, but then the same compass error comes up again (repeatedly through every flight), and when trying to fly straight (yes, I've confirmed in the command inputs that I'm not pushing the stick to the sides...) it yaws and deviates slightly, normally to the left.

I will ultimately have to reach out to DJI to either have it repaired (one more time) or replaced, but wanted to see if this is an inherited problem with the Phantom 3, or whether there are people flying them without any compass errors.

SKYER
“Fly your drone as though you were flying in it yourself…”
See aerial short films at my YouTube Channel: https://www.youtube.com/channel/UC304REG4t2_OWJmQDHLvQ2w  

skyer333 Posted at 2016-10-30 09:23
Thanks Rnfaust. As mentioned in the original post, I've carried out the calibrations in locations  ...

I was going to keep quiet about this, but I'm starting to see some similarities now to a problem I had 2 days ago. People have been helping me on the Phantom Pilot Forum. You may want to read my thread and see what you think.
I usually fly Litchi autonomous missions and it would be catastrophic if a large error happened during one of those. I think I'll call DJI next week and see if they can interpret my internal flight logs. Have a look:
http://www.phantompilots.com/threads/compass-error-cause-or-correlation.94275/#post-975205

Oh, and good luck. I'll be watching your thread for an answer to this problem.

just cut to the end
order a new compass or landing leg with compass
10-20 dollars us

seems a fair number have this issue while most others don't.
kinda says bad compass board or something in a batch...

no harm , no foal,
and maybe you fix it for 10 bucks and an hour time

kirk2579@aol.co Posted at 2016-10-30 01:13
just cut to the end
order a new compass or landing leg with compass
10-20 dollars us

With all due respect, that is not the point. If you spend $800 on a high-end cell phone or tablet, you would not expect to have to buy a replacement antenna and figure out how to repair it yourself if it didn't work properly right out of the box, potentially voiding the warranty in the process, and without assurance of what the root cause was in the first place.

Also, taking the "fix it yourself" aproach is not going to help DJI document and identify a potential quality escape, if indeed there is a batch of units that were produced with faulty compass or other components.

I'm just trying to confirm whether this recurring compass issue is ultimately a limitation/shortfall of the P3A, or whether a "good" P3A will not loose GPS lock often, as seems to be the case.

Thanks everyone for the constructive feedback!

skyer333 Posted at 2016-10-30 08:35
With all due respect, that is not the point. If you spend $800 on a high-end cell phone or tablet, ...

I am sorry
didn't mean to irritate you.
take care and have fun flying!

kirk2579@aol.co Posted at 2016-10-30 16:16
I am sorry
didn't mean to irritate you.
take care and have fun flying!

I was not irritated, just wanted to clarify why I started the thread. Sorry if my reply came out a bit blunt.

I do appreciate everyone's input. Thanks!

kirk2579@aol.co Posted at 2016-10-30 16:16
I am sorry
didn't mean to irritate you.
take care and have fun flying!

I was not irritated, just wanted to clarify why I started the thread. Sorry if my reply came out a bit blunt.

I do appreciate everyone's input. Thanks!

skyer333 Posted at 2016-10-30 20:34
I was not irritated, just wanted to clarify why I started the thread. Sorry if my reply came out a ...

no problem,

basically was saying

no it is NOT normal
you should really not have compass issues unless sitting on metal etc.

until a short time ago this was NEVER even mention as an issue on p3's
then a bunch of posts rapidly... about compass not working, calibration's etc.

then they slowed down

read posts that dji fixed by new compass install for those sent in
read some (not everyone in warranty or cares)
simply fixed in an hour for $10

was just trying to pass it on since you asked.

so to sum it up your P3 is not normal at this point by your description.

I see these error messages constantly. I've tried recalibrating the compass more times than I can count too.

I'm going get data that DJI-ken has asked for in another thread but this is getting ridiculous.. I'm even seeing the "toilet swirl" and the phantom listing to one direction when I try to fly.

davido-1138 Posted at 2016-10-31 12:56
I see these error messages constantly. I've tried recalibrating the compass more times than I can co ...

once a good compass is calibrated you should not need do it again for long time if no crashes etc.


the way  I see it 2 options

follow through with Ken and send in when he tells you to.
he knows his stuff ands helps many folks

or

try do it yourself approach with new compass
but prior to that make sure both ends of compass cable solidly connected
inside leg module and maybe even the MB -

its all what ever works best for you!

good luck and have fun flying!

Thanks everyone for sharing your experiences and perspectives.

There seems to be a consensus that unless you are taking off or flying very close to large metal objects, or someting that can cause electromagnetic interference, it is definitely not normal to see repetitive compass errors. And when it happens, the ultimate solution seems to be replacing the landing gear that holds the compass module antenna. I hope to confirm that was indeed the fix, once I receive my Phantom back from the DJI service center later this week.

Stay tuned...

PS. For those in the US, don't forget to vote tomorrow!

skyer333 Posted at 2016-11-8 15:32
Thanks everyone for sharing your experiences and perspectives.

There seems to be a consensus that u ...

One additional question I will ask is if you have attached any after-market objects to the aircraft? BTW, I have only once calibrated my compass, about 13 months ago, I never get the compass error message, and I am flying on firmware 1.6.

Geebax Posted at 2016-11-8 00:31
One additional question I will ask is if you have attached any after-market objects to the aircraf ...

Hey Geebax. I have no aftermarket parts or any mods on my P3A.

There seems to be different schools of thought between "calibrate the compass every time you fly in a different location" (DJI's official recommendation) and "once you have a good calibration, don't mess with it". I guess as long as you don't get compass calibration or error warnings from the app AND the aircraft performs well (flies straight, holds position, etc), there should be no reason to do a compass calibration.

skyer333 Posted at 2016-11-8 09:24
Hey Geebax. I have no aftermarket parts or any mods on my P3A.

There seems to be different school ...

Like geebax I calibrated my P3A compass, just once, about 4 months ago. Mind you, my flights are all within 100 miles of where I calibrated.
Anyway, my partner, who calibrated same as I did, just started seeing messages- compass error, ATT mode a couple of times & without even calling DJI, bought a new leg/compass, 12 bucks I think , installed it & has never seen or had that message again.
He assumes his compass went wonky, but didn't want to wait for a fix when it looked easy to try for minimum dollars. If his fix hadn't worked, he would have then sent his bird in for inspection

fans987d278a Posted at 2016-11-8 10:34
Like geebax I calibrated my P3A compass, just once, about 4 months ago. Mind you, my flights are a ...

Thanks for sharing!

SKYER
“Fly your drone as though you were flying in it yourself…”
See aerial short films at my YouTube Channel: https://www.youtube.com/channel/UC304REG4t2_OWJmQDHLvQ2w  

skyer333 Posted at 2016-11-9 01:24
Hey Geebax. I have no aftermarket parts or any mods on my P3A.

There seems to be different school ...

Ok on the mods, I ask because they may affect the compass. With regard to compass calibration, I have flown all over our state, which is small but I have never recalibrated the compass and I figure it shows that you really do not need to. And it is not as if the calibration fades away, or gets out of date or anything like that.