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DJI Mavic Pro Compass Nro. 2 Not Connected


Aug 1, 2018
Hello Guys. Please I need your help:

- A couple of weeks ago I had a crash.
- My drone fell from around 4 meters high.
- The following components got broken:
- The four propellers.
- The upper side of the aircraft plastic body (at the rear, where it says "DJI" with white letters).
- The fan (the part that rotates was still rotating, but it got separated from its case, so while rotating it was hitting all its surroundings).
- The rear right motor/engine (it started to make a continuos bip bip bip bip).
- It was not possible to upgrade the firmwares of the aircraft and the remote controller (it both scenarios the upgrade process displayed an error when reaching the 40% of the installation process).

Based on what I explained above, I already did the following:
- I replaced the four propellers.
- I replaced the upper side of the plastic "body".
- I replaced the fan (it was quite difficult to find the spare and then to replace it).
- I replaced the rear right motor/engine (no more bips now).

- After doing all those replacements, things improved a lot:
- I was able to upgrade the aircraft & the remote controller to their latest firmware available using the Assistant Application.
- I updated the DJI Assistance 2 in the mobile that I use with the remote controller (the mobile it's an LG V20).

- When I tried to calibrate the two compasses, I got successfull confirmation for the calibration of Compass Nº 1 (the one which is together with the GPS at the rear).
- But for Compass Nº 2, the remote controller says that it's not connected.
- According my understanding, the Compass Nº 2 is the one which is located at the front of the aircraft (see attached .JPG file).
- I know that I had been "working" a lot on that region (I had to unscrew the screw, separating the compass small board from its location in order to replace the fan). I did this procedure a few times being very carefully.
- The thing is that I know that Compass Nº 2 "is there" (screwed properly again in its correct position).
- Although I tried demagnetizing the front part of the aircraft (during many minutes, using a small square shape demagnetizer), when I switch on the aircraft, the DJI Assitance 2 in the mobile unit (connected to the remote controller) says that Compass Nº 2 is Not Connected (while it shows that Compass Nº 1 is with a small green line).

- If logs are needed to get deeper on this problem, ¿Would anyone explain me how to obtain those logs?
- I already bought a spare of the Compass Nº 1 (meaning: I got myself auto-convinced that, while handling the compass, I might had burned an electronic component of the board, just with my body electricity).
- The spare part brings the small board with the cable, but not the "whole" cable. It brings just a few centimeters of cable with the tip already prepared to be soldered to the existing cable. ¿Does anyone have a video or some instructions or any tips that must be considered for this spare replacement?

Sorry for my "Spanglish". I did my best, :)
Thank You Very Much.


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Sorry I cannot help you but maybe @Thunderdrones can tell you and pretty sure he will see this .
Good luck .
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Sorry Dirkclod, ¿Which steps should I follow in order to ask help to @Thunderdrones sharing with him the explanation of the problem I am having?
He will see where I flaged him and when he logs on he will see it so just give him a chance. He does all my work as well as a lot of others .He is good and should be able to tell you what you need .
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OP, check all the wires on the compass, there are 4. They break easily. Also check the compass wires on the FC board, they break easily too. If 1 of the wires is not making contact, there will be a compass disconnect.
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¡¡ Hi Thunderdrones !! It's very nice to get in touch with you. Thank you for your fast response providing your help on this matter. I will check those 4 wires you mentioned. I know how to "open" the aircraft cabinet from its upper side and then how to verify those 4 connections in the front part of the aircraft. However, I don't know which one is the FC board. ¿Is it the first board that you can see when taking out the below part of the aircraft plastic body? ¿Or is it the second board that can be seen after taking the first board away (duty that seems not to be easy to do :()? Thank You Very Much Again. My Best & Kindly Regards. :)
Hi Thunderdrones. I found where -in the board- those 4 small cables were connected to. And as you said, although it seemed that the four cables were connected OK, two of them were not. Since then, I welded the four cables again (the other two got disconnected when trying to remove the white glue) and then, "voilá", I have just successfully calibrated the two compasses in the aircraft. THANK YOU VERY MUCH FOR YOUR HELP. :):):):)
Hi Thunderdrones. I found where -in the board- those 4 small cables were connected to. And as you said, although it seemed that the four cables were connected OK, two of them were not. Since then, I welded the four cables again (the other two got disconnected when trying to remove the white glue) and then, "voilá", I have just successfully calibrated the two compasses in the aircraft. THANK YOU VERY MUCH FOR YOUR HELP. :):):):)

Job well done!
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¡¡ Hi Thunderdrones !! Yes, job well done, THANKS TO YOU that told me the "tip". :)

Well, it seems that I have another problem (I hope this is the last one; it seems that when resolving one problem, another "minor" issue is reported by the aircraft, as if the drone goes alerting critical problems first, then the majors, and finally the minor ones): Now that all the compass errors have gone away, the aircraft is displaying "Visual System Error" (please see first attached .jpeg file; the error is in Spanish).

The first thing I tried to do was to perform a calibration using the DJI Assistant 2. Althought the Assistant displayed that the sensors status were OK (please see second attached .jpeg file), when trying to calibrate with my computer screen displaying all the black spots and the green square, there was no way to make the aircraft to display the red square that must syncronize with the other square to start the calibration process.

In the mobile unit, I could see that "Sensor Visual" is in "Normal State". Since then, I tried adjusting the stabilizer. The stabilizer adjust process was successfull 100%. Then, I tried calibrating again the aircraft against the "black spots screen" but again, the red square was never displayed (just the green one alone was there).

During all these tasks I made, the only log file (.DAT) generated is the one I'm attaching in this post (please see third attached file). I could not find anything else.

Well, I hope I have explained myself as clearer as possible.
Thank You Very Much Again Thunderdrones.
My Best & Kindly Regards.
César Villagra


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Look at your gimbal PCB and make sure both ribbon cables are connected, derecha and
izquierda. You should be seeing a picture out of each of them.

Gimbal PCB.jpg
Well, you were right. Although the problem was not about the connectors; it was related with the cables of those connectors. Both of them are broken (see <<FrontVisionProblem.jpeg>>). About their replacement, ¿Do I have to buy the whole front vision module (see <<FrontVisionSpare.jpg>>)? ¿Or those two yellow cables are sold separatelly? If yes, ¿Do you know the spare part name of those two cables for the Front Vision Module? ¡¡THANK YOU!!


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Yes, I'm in Argentina. It's quite difficult for us to find & buy spare parts. In fact, I have just found the spare in an Argentinean Web Page ( and the cost is AR$ 10.000 (around USD 357,00). URL: Frente Pro Mavic Dji Ver Componente Visión Obstáculo Función - $ 9.817,70).

As you can see, when you find the spare in Argentina, you have to pay a lot of money. I also found the spare in Amazon and eBay (prices go from USD 42 up to USD 54). But eBay and Amazon do not ship anything to Argentina.

So first, I must buy the spare part and ask for its delivery to Minden (NV) to a company named "SHIPITO" ( Once the item arrives there, then I'm able to ask Shipito to deliver the item to Argentina (using a Courier as FEDEX or DHL). I must never use USPS, since USPS has an agreement with the Argentinean Post Company (Correo Argentino). If I use USPS, then "Correo Argentino" leaves the product in Argentinean Customs, and it's almost impossible to take it out (you have to fill in a lo of papers, then go to customs, make the queue, wait not less than 4 hours (if you're lucky), etc. etc.). Instead, if I use FEDEX or DHL, the must deliver the product to my home directly. :)
Just to know: ¿How do I know if a spare part was really manufactured by DJI? I trying looking for the spare part in the official DJI web page and it's not displayed as available. Thus, I found 4 spare parts in Amazon and 1 in eBay (see below URLs). If it's not possible to know if these spare parts were manufactured by DJI (asking to the vendors does not mean they will tell the truth :(), ¿Is there any tip that I can see in the pictures that might "tell me" that one spare part is better than another one?
DJI Mavic Pro Drone Front Vision Position Sensors modules Forward- Fast Shipping 190021286559 | eBay
Some sellers sell copies that dont work, but look like they are DJI. I sell OEM DJI sensors. $49 shipped to you, but it might take a few weeks to get to you.
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