How to fix when your Phantom 3 is getting the error NO MC DATA ACCELEROMETER FAILED and gimbal cannot receive MC data.

Hello all,
I have posted this in a couple of other threads, I just want to make sure that it gets seen.  I hate to think about people having to ship the brand-new Phantom to DJI and wait 8 plus weeks to get it back and to top it off you find out that it's not covered under warranty because you crashed it.  So I apologize for the redundancy in advance.

Let me start off by saying I'm not a newbie when it comes to flying quads, hexs and RC Helis for many years. However, I am when it comes to DJI Phantom's.   That being said what happened to mine was still a result of my own fault.   Initially in the settings I set my RTH at 15% battery power.  My battery was low I had my phantom hovering about 4 feet high and I was walking with the Phantom front of me down the sidewalk back to my house from the park .  My battery level was 16% and I started to land it,  it must've switched to 15% right at that very moment when the Phantom decided to RTH then immediately started elevating in altitude smacked into a tree branch that I was under, then rolled 90° and from about 6 foot elevation crashed into the sidewalk.  Aesthetically the aircraft seem fine just a couple of scratches on the two arms it hit the sidewalk. However after recharging the battery and trying to restart the aircraft  within 30 to 60 seconds get the NO MC DATA-  ACCELEROMETER FAILED error and gimbal cannot receive MC data.  The gimbal was producing the DD DD DD DD DD error tones and the camera was limp.  I could not calibrate the IMU.

So here's what I did to fix it. (Note: You may want to read Zandegran's post below and try before disassembly. Could save you some time.)
Once I disassembled the top cover "see videos below. not mine" I located a large black box "see picture below the videos" in the middle of printed circuit board that has four small tabs that you very carefully "you do not want to break these tabs they're very important, take your time!!" pry back the tabs using a very small jewelers screwdriver in order to remove the lid of the black box. There's a small data ribbon that goes into the blackbox connecting to the accelerometer  from the printed circuit board,  you'll need to unplug that from the printed circuit board as well.  When you remove the lid of the little black box the accelerometer will stay attached via two-sided foam tape to the lid portion of the black box.  Now this is the part that I found kind of funny, you will need to give a technical tap...  Meaning, by giving it this tap you free up whatever got stuck in the internal components of the accelerometer during impact.  From whatever direction the aircraft had hit on impact you will need to tap the opposite side of the accelerometer firmly on  something like a cutting board.  The amount of pressure I tapped mine with would be comparable to one solid door knock.  The article that supports tapping of an accelerometer to fix it.  I got from this post read post number 18 http://www.phantompilots.com/threads/red-green-yellow.133/ After doing this I reassemble the accelerometer leaving the lid off the GPS was still not connected I powered the The Phantom up and bam no more DD DD DD DD DD error tones from the gimbal and the camera leveled off and functioned perfectly.  So I went ahead connected the GPS and snapped everything together minus putting the screws back in.   Placed the Phantom on a level surface and recalibrated IMU and then recalibrated the compass.  Again success.  I went ahead and completed the assembly of the Phantom 3 and took it out for a test flight.  After 12 flights or 3.5 hours of flight time, the aircraft is flying fine.

I found a video on YouTube here's the link on how to disassemble the phantom 3 and the second .


I think it would be nice if DJI can make some kind of a screen flashes indicating that the RTH was about to happen versus just the audio tones unfortunately I had my iPad mini volume turned down and failed to get the ten second audio warning.  In addition I think that DJI could add a little bit more foam to encapsulate the accelerometer in.  This would ensure it will withstand more shock.

Just take your time and good luck.
-Dog

Well, on the one hand it looks like

DANGER WILL ROBINSON  YOU HAVE JUST VIOLATED YOUR WARRANTY!!

On the other hand, I guess if you're that brave and don't want to wait six weeks (or the expense) of sending it to a repair center.....

Thanks for sharing.

aburkefl@gmail. Posted at 2015-6-9 19:55
Well, on the one hand it looks like

DANGER WILL ROBINSON  YOU HAVE JUST VIOLATED YOUR WARRANTY!!

You are correct. However warranty does not cover if you crash the P3.   So yes, not having to wait six weeks or more and paying a grip for repair seems like a likely decision for me.

-Dog

DivenDog Posted at 2015-6-9 21:37
You are correct. However warranty does not cover if you crash the P3.   So yes, not having to wait  ...

Well, a crash should not automatically void your warranty. If one could prove a failure on the part of the equipment....

But, essentially I agree.

Did you watch those videos where the guy took his Phantom apart - right out of the box? Now, there's a brave man - or a guy who can afford more than I.

aburkefl@gmail. Posted at 2015-6-10 02:33
Well, a crash should not automatically void your warranty. If one could prove a failure on the par ...

Yeah I agree on that one!  I  would say that's a case of  more money than brains.

-Dog

Thank you for all Dive-N-Dog .!

Very useful info, thanks!

So Dog-

You say," if caused by impact ".
If not caused by a crash do we try this method also? Just because.

I myself, (not crash related) would have at least tried before it was sent away.
Warranty or No.



Cheers!!

                                                                                             BBB

Same fix For the P2. The Master Controller has little gyros in it that would get stuck after a crash.  Removing it and giving it sharp rap on one side would free them up.  ( the sandwich (gyro) spelled the same way, love that lamb )

FlyGirl Posted at 2015-6-11 23:17
So Dog-

You say," if caused by impact ".

I would assume, it may have suffered shock during shipping.  It seems that the sensor is pretty sensitive. No punt intended.   However that would be covered under warranty.

-Dog

veteranpilot Posted at 2015-6-11 03:34
Thank you for all Dive-N-Dog .!

Your welcome... So it worked for you?
-Dog

Dive-N-Dog Posted at 2015-6-12 07:24
Your welcome... So it worked for you?
-Dog

Thanks for asking,

Did not work for me.


Cheers

                                                                                           BBB

FlyGirl Posted at 2015-6-12 10:49
Thanks for asking,

Did not work for me.

Sorry,
That was meant for veteranpilot, not you fly girl. You had previously mentoined you shipped your P3 back to DJI before you had seen my post.
-Dog

  Your welcome... So it worked for you?
-Dog

Hi Dive-N-Dog.!  your info fixed my problem.!  All function is normal,  thank you so much.

SOLVED : also without sending it back, I must add. I have posted this solution in couple threads and have solved many people's problem. That's why I'm starting this new thread.
Thanks to the user DivenDog. His method includes opening the device. I must admit that I found out this technique after reading his post.

What happened
I got the drone delivered before work. i was so eager to fly it. I did not charge the battery which is low.. I flew it. I did not mind the low battery thinking that it has the safe return feature. I was in the road in front of my house and I found that a car is leaving the parking and my drone is in automatic descent. I did some manoeuvres to avoid the car and crashed the drone in the building some 30 feet above. It came down scratching the building all the way. I rushed to it and turned it off. I found some scratches. Propellers are ruined. I thought I got lucky and went to work.
After coming back and tried to fly and I got this error. I tried pushing in the gimbal cable, power cycling it many times, etc. I tried to calibrate IMU and It was giving the error "Unknown error" at 35% the first time and at 2% after that.
I called DJI US though I live in Sweden.. It's already evening. After waiting for 42 minutes, I talked to the technical support people and they said I have to send the drone in and it will take 4 to 6 weeks for them to fix it as they have queue. I have trips planned and I decided to open it tomorrow as I do not have the tools to open it today.

How I fixed
Since, I decided to open it tomorrow. I looked for some help and I landed in this thread . I decided to try smacking the aircraft. It's not some random decision. I will explain why in the "What I learned" part. Since the error is caused by the aircraft hitting the front, I smacked thrice on the back of the aircraft. I turned the aircraft on, went to the sensors page and sensed (explained how in the next section) that the IMU calibration will go through and it did. Then I took the craft and flew it.

What I learned
I also do mobile development and I know how the digital accelerometers work (A metal on a diaphram moves in a magnetic field to generate current) and have seen raw values of gyroscope, accelerometer reading of mobile devices. when I went to the sensors menu in the advanced settings, I saw this.



I did this, when I could not calibrate(the screenshot was taken later). I saw the value -16 in the accelerometer's X. Initially I didn't care much. After smacking (with the device off), it was showing the normal values (around negative 1 to positive 1), as shown in the screenshot. Then the calibration went through.
I know that the gravity affects these values. So, rotating the craft in different direction changes these values in different axis. The X though was not changed. It's stuck. This made me think that the metal on the diaphram of the acclerometer is stuck and I need to smack it in the opposite direction to release it (and not make it get stuck in the opposite direction). So there is a chance it's stuck in either of the six directions and based on that you have to decide where to smack.
Solution: This is where you need to smack, (might be a combination of smacks, if it's stuck in more than one axis) based on the acceleromater values.
low negative X - back (as the metal is lodged on the back of the craft by got hit on the front)
high positive X - front
low negative Y - left (nose pointing away from u)
high positive Y - right (nose pointing away from u)
low negative Z - bottom
high positive Z - top

I hope this will help. Good Luck.

zandegran Posted at 2015-6-12 17:28
SOLVED  DivenDog's comment make's sense and here is How I solved after reading his comment. Also s ...

Been following this thread with some interest. It's downright fascinating. Can't you see it now?

"Bring your quad to Harbor Freight Tools for repair.
We have all sizes of hammers!" LOL

Glad you guys figured that angle out. My fear is that if I start taking things apart, I'm going to end up with extra parts left over! (Like a kid "fixing" a watch!)

aburkefl@gmail. Posted at 2015-6-12 21:06
Been following this thread with some interest. It's downright fascinating. Can't you see it now?

" ...

True.. That's why I was reluctant to open it.. Anyhow, now it's fixed without loosening a single screw.. Flew it 6 times after it and things are as fine as a breeze

zandegran Posted at 2015-6-14 07:12
True.. That's why I was reluctant to open it.. Anyhow, now it's fixed without loosening a single s ...

Glad to hear it!  Mine has been perfect since I did the repair that motivated me to create this post.  I am happy to see that this fix is helping other P3 owners flying instead of waiting on repair.

Please keep posting your stories.
-Dog

zandegran Posted at 2015-6-12 17:28
SOLVED  DivenDog's comment make's sense and here is How I solved after reading his comment. Also s ...

Thank for your help. I have problem with x value

zandegran Posted at 2015-6-12 17:28
SOLVED  DivenDog's comment make's sense and here is How I solved after reading his comment. Also s ...

Thank for your help. I have problem with x value

playex Posted at 2015-6-17 08:26
Thank for your help. I have problem with x value

Hey Playex,
Thanks for sharing with us.  Did you get your P3 fixed and back flying?

-Dog

Dive-N-Dog Posted at 2015-6-18 00:49
Hey Playex,
Thanks for sharing with us.  Did you get your P3 fixed and back flying?

Hi Dog

Unfortunately not. IMU calibration fails. I spent a lot of time and nothing

I am waiting response from support@dji.com


Thanks for ask
Playex

playex Posted at 2015-6-18 09:23
Hi Dog

Unfortunately not. IMU calibration fails. I spent a lot of time and nothing

Did you try the recommendations from Zandegran's post in this thread?

-Dog

Dive-N-Dog Posted at 2015-6-18 12:53
Did you try the recommendations from Zandegran's post in this thread?

-Dog

That  is an interesting post. I did in the direction indicated and after in both direction and the x value keep  -16.04.  No more smack

playex Posted at 2015-6-18 13:24
That  is an interesting post. I did in the direction indicated and after in both direction and the ...

Try Smacking on the backside of the Craft, a hard one (with your palm). It should solve the problem. Let us know the outcome..

zandegran Posted at 2015-6-19 04:25
Try Smacking on the backside of the Craft, a hard one (with your palm). It should solve the proble ...

Can not believe it ,  it worked !!
Thank you very much Zandegran. Thank you very much Dog .

This is what I did:
First I put the gimbal protector and also the foamy protector  .
Firmly I take up the aircraft and prepared the back of the battery and turn to me to give a smack  with my right palm of my hand.
I took a deep breath and I did the smack.
Both protector  flew.
In the first moment I thought that I did  very hard and broken something inside.
Was still incredulous , then turn on the RC , connect iPad .
Then I turned on the aircraft and when I see the app. Oh surprise!,
the x value had dropped to -0.1 .
What a sorprise so great. !!
After that I Calibrate the compass and turned on the engines. Work.
The battery was low and I plug to charge.
Immediately I thought of writing this replay at the Forum.
Sorry my english
Thanks everyone for your help.

playex Posted at 2015-6-18 13:24
That  is an interesting post. I did in the direction indicated and after in both direction and the ...

Can not believe it ,  it worked !! Thank you very much Zandegran. Thank you very much Dog .

This is what I did:
First I put the gimbal protector and also the foamy protector  .
Firmly I take up the aircraft and prepared the back of the battery and turn to me to give a smack  with my right palm of my hand.
I took a deep breath and I did the smack.
Both protector  flew. In the first moment I thought that I did  very hard and broken something inside.
Was still incredulous , then turn on the RC , connect iPad .
Then I turned on the aircraft and when I see the app. Oh surprise!, the x value had dropped to -0.1 .
What a sorprise so great. !!
After that I Calibrate the compass and turned on the engines. Work.
The battery was low and I plug to charge.
Immediately I thought of writing this replay at the Forum.
Sorry my english
Thanks everyone for your help.

playex Posted at 2015-6-19 12:13
Can not believe it ,  it worked !! Thank you very much Zandegran. Thank you very much Dog .

Thi ...

Nice work Playex!! Way to stick at it and fix it yourself!  Thanks again for sharing with us.  

-Dog

Dive-N-Dog Posted at 2015-6-20 13:15
Nice work Playex!! Way to stick at it and fix it yourself!  Thanks again for sharing with us.  

-D ...

What was that character on the A-Team always saying? "I love it when a plan comes together!"

@aburkefl

The captain from A-Team is John "Hannibal" Smith.

Anyways, my Phantom 3 Advanced experienced the same issue and after finding this thread, going to give the solution above a try! I'm glad we have some technical folks to find and try things out! I really do NOT want to be waiting weeks at a time when if it's a simple "technical tap" after dis-assembly.

Thanks again to DivenDog and others!!!!

Happy to report after disassembling and tapping or so on the accelerometer, then leaving the top off, MC Data error was gone! I calibrated the IMU and camera/gimbal. Next step is to assemble, calibrate and GPS, and hopefully do a test flight. But so far no more MC data error!!!  I think things are looking good and want to thank those that contributed to this thread!

robvelez@gmail. Posted at 2015-6-21 03:33
@aburkefl

The captain from A-Team is John "Hannibal" Smith.

Kind of ironic my  coworkers call me A-Team because my name is Aaron and I am always saying  "I pity the fool!"
Anyways I am stoked to see that this is helping P3 owners and they are not having to send the P3's away for who knows how long to get repaired.

Again thanks for sharing and glad to hear your up again!!

-Dog

Hello! I will start off with saying I have never wrote in a forum... ever! SO hello for the first time! Second, I am new to this world of any flying device! I purchased the Phantom 3 to expand my real estate photography skills, and WHOA it has helped. I haven't flown it high at all, and its super stressful as I live in a swamp preserve with lots of tall trees! It has been great... until yesterday when a tiny little tree decided to meet my sweet lil drone :-( ugh. Im having all the same issues, IMU won't calibrate, Accelerometer failed, gimbal cannot receive MC data. I did the following steps suggested by everyone, and its still not working. Disclaimer, I am sorta confused as where you all are "smacking" the drone... I don't have any tools to even attempt to take it apart, which is going to be a few more moments of courage to even do that! Im thinking of taking it to a place that works on tablets, phones, etc and seeing if they understand some of this talk more than I do! Thank you for these posts as its giving me some insight. Im usually pretty handy, but this is a whole new world! ~T

Tdogg Posted at 2015-6-24 07:01
Hello! I will start off with saying I have never wrote in a forum... ever! SO hello for the first ti ...

I just realized my Y Acceleration is at -16

Tdogg Posted at 2015-6-24 08:11
I just realized my Y Acceleration is at -16

With Y being negative you want to give it a good hard thump on the left front or nose with the P3 pointing away from you. Make sure you secure the camera with the stablizer, the one it shipped with.


-Dog

Hello all, man I'm so excited I could run around planet earth and back again! It WORKED!!! I'm talking about the recommendation that Div-N-Dog made, that Zandegran followed up with and that Playex also gleefully explained. Smacking the Phantom 3 (Professional) on the opposite side of the crash REALLY works!  I just finished test flying my brand new out-of-box P3 for the first time in a couple of days because after I had done a recommended Firmware Update my P3 went BoNkErS (yes like the spelling of this word)! It was depressing not realizing why and what had taken place. I was scrambling; reading forums, calling various tech supports only to be disappointed by all of them, even the fact of hearing that the authorized dealer I purchased it from told me that they wouldn't take the unit back and give a replacement that would have to contact DJI directly for support. I prayed to God for help, ran across this forum, implemented the instructions suggested by Div-N-Dog and the rest is history! Yippee!!!

After I did the upgrade the unit went berserk on me crashing like a runaway freight train. I tried to start up the aircraft and when I did I got Flashing Red & Green lights on the Rear Side. There was no response from the Controller to the P3 and to top it off I got a software error message that said "MC Data Error". I read somewhere to try and calibrate the IMU but when I tried to do so it stalled out at 16% and after several other attempts it levelled off at the 2% progress point and generated a message that said "Unknown Error".  

For those of you who have fears and doubts thinking that it sounds cynical smacking your P3 in this type situation - Don't! The thing is, (although sensitive in electronics), sturdier than you think. Applying a good solid amount of pressure (not with a sledge hammer though), you'll find will do the trick if your situation was like mine and the others who found this technique to work. Caution: Use your own judgment!

I couldn't imagine the nightmare I would run into dealing with DJI about fixing this thing, let alone give me a new one. I was desperate and was willing to try almost anything in a one-last-ditch effort to get my P3 working again. And I did. I'm grateful!  

Thanks Div-N-Dog, Zandegran, & Playex and others of you who might have said/applied this fix. I appreciate you all sharing you testimonies. I'm a believer!

anthony.ampphot Posted at 2015-6-28 11:25
Hello all, man I'm so excited I could run around planet earth and back again! It WORKED!!! I'm talki ...

Wow! Great share!  I am so glad to hear that you're back flying and not waiting!

-Dog

zandegran Posted at 2015-6-12 17:28
SOLVED  DivenDog's comment make's sense and here is How I solved after reading his comment. Also s ...

Hey! Worked for me! Thanks a bunch.

I can't believe that with this technological marvel, the thing I needed to was pull a "Fonzie" with a rubber mallet.

I crashed full speed forward into a telephone pole. I thought I was behind it, but you know how good depth perception is at 40 yards away. My camera was busted off into two pieces and the ribbon cable was ripped apart.

I ordered a new ribbon. Took hours of time to replace it carefully. Upon restart, I got an IMU error, but my error said I should check the 8-wire connector to the gimbal. Naturally, since I (a) fixed the camera back into one piece using super glue, (b) just removed and fixed the gimbal, and (c) replaced the ribbon wire, I accepted what the DJI app error message was telling me, and that the problem was certainly gimbal and wiring related.

After redoing my work twice, I realized I could not do it any better, and was almost at the point of sending it in for the 5-6 weeks of slow customer service and mucho $$ DJI wants to repair. Then I found your post Zandergran.

At first, I have to admit I thought you were a troll and full of it. But enough people said it worked for them. And you pointed me at the sensor readouts, which confirmed that my accelerometer was faulty. So, I followed your advice and hit the Phantom 3 on the battery pack. It wasn't until the 3rd hit that I hit it hard enough. It worked, and then I could re-calibrate the IMU without errors.

My gimbal was still a little bent out of shape, but after recalibrating it too, it all works great.

Unbelievable. A rubber hammer?! That's what it takes to fix this $1,200 technology marvel?

Thanks!

PS: I did not take it apart as the OP in this thread suggests. I suppose that would be safer for the other components that also took the brunt of the rubber hammer. But I had lost patience, and just hitting the quad on the battery pack worked for me.

zandegran Posted at 2015-6-12 17:28
SOLVED  DivenDog's comment make's sense and here is How I solved after reading his comment. Also s ...

Question.....

I did the same thing as you have stated. What i found was that all of the axis nubers changed when i hand held it and turn it but the compass numbers did not register.   They all remained at 0.00

any advice?  thanks!

sam.mediamanav Posted at 2015-7-17 08:25
Question.....

I did the same thing as you have stated. What i found was that all of the axis nube ...

Sounds to me like the compass is failing.  Are you getting a MC Data error?

-Dog