Yet Another Disconnection Error, a detailed troubleshoot and error opinion

Hi all, Relatively new to drones.

I currently own a Mavic Air and a 2nd hand Mavic 2 Pro. I'm having multiple remote controller Connection errors while using the Mavic 2 Pro.

Let me set the scene. Went out with the drone yesterday 30th August 2020, I know date isn't important, anyway, I Placed my phone in the RC and Connected with originally supplied (Mavic 2 Cable the side port is being used) RC Cable, turned RC on and the phone starts charging as expected (a Galaxy S10, Current android firmware, latest DJI Go 4 app and latest AC Firmware and 4G network active) turned on the aircraft, after a few seconds DJI Go 4 displays the error 'Remote Controller Connection Error' shortly followed by the Phone disconnecting from the from the RC/AC.

Fortunately I was on the ground at the time and the props were started. so I replace the cable with my Mavic Air cable and again the same thing happens (No disconnection issues with this cable while flying my Air this I believe eliminates the cable being at fault). So now I Decide to format both my SD Card and Internal Storage as I am aware of SD Cards causing issues even though this particular card is brand new early stages of troubleshooting is why I didn't remove SD Card, Clear DJI Go 4 App and video cache then uninstall app and reinstall app, updated AC Firmware via GO 4, fire up the RC and AC in the normal way as in 4G Network Active, again same issue.

Next this is the bit that stumps me, If I Put my phone in Airplane Mode prior to turning on RC this issue disappears and I can fly using my 3 batteries with no issues I am also not restarting GO 4 App between battery replacements just turning off the AC.  Next I went home and using DJI Assistant 2 (again latest version), I refresh the firmware on the Aircraft.

Again I setup in the house on the floor (at this point the AC and RC/Phone are on and stationary on the floor and not being touched prior to switching on the AC) and everything works fine for 30 to 40 seconds and disconnection again (this would eliminate the RC USB Port connection, as this error occurs even while the RC is stationary on the floor and the cable is not being manipulated) switch phone to Airplane Mode and restart app then AC props off and wait for a few minutes, no issues, so, now I try with 4G Data active and what do you know, no issues.

I do apologise for the length of this post and I have read about errors with disconnection issues and troubleshooting tips on google and couldn't find anything that's similar to the issue that I'm experiencing.

Now I have dabbled with creating software with a few PC Based Languages in the past and most recently x86 Assembly Language, and PICASM for Microcontrollers Also, and understand a few things about troubleshooting for bugs in code and hardware and the many issues some bugs throw up, however, I may also be wrong in my diagnosis of this error.

To me it appears that the issue I'm experiencing is less likely to be a hardware issue and more likely to be a Software issue that is located within the code of the Go 4 App, namely within the initial Network startup code. I'm wondering if others having this same issue with Remote Controller Disconnections, would their issues be remedied by deactivating Network Connectivity prior to starting the DJI Go 4 App and starting of the props. and activating the network after confirming that this issue is resolved in airplane mode by observing for a few minutes while the AC sits doing nothing with props off but AC on. then starting props and then activating Network Connection, I know this won't resolve all disconnection issues and some issues will be resolved with new cables. There does seem to be many Remote Controller Disconnection enquiries on the web.

Thanks in Advance

Carl

P.S I love the Mavic 2 and the DJI Go 4 App Layout DJI Please don't change it, if you do Allow the user to activate/Deactivate on screen features, If it ain't broke don't fix it.

Why would you need Network Connection during flight? Having interruption by incoming call is a big NO in drone business. Always fly with device in Airplane Mode ...

Hello there Carl_W. I am sorry for the trouble this has caused and thank you for reaching out. In addition to this thread putting the mobile phone in Airplane mode while flying would lessen the interference like receiving calls and text messages while on flight. In addition, it is not necessary to put your device in Airplane mode but please make sure there is no such calls/text message or any notification that will interrupt you when using your device while flying your DJI Drone. Thank you and have a safe flight always.

Exactly the same issue here. I have 3 types of drones, which use the djigo4 app. The issue comes only on the M2P. I have never experienced this with my Air1 or my Spark (OTG connected). I think this  is a Sw bug, which is releated to the Mavic2 series. I have no issue with the djifly app using the same phone (Samsung Note8) with the  Mini and Air2.  I use the original DJIGO app also with Phantom3 series with zero issue.

DJI Stephen Posted at 8-31 19:43
Hello there Carl_W. I am sorry for the trouble this has caused and thank you for reaching out. In addition to this thread putting the mobile phone in Airplane mode while flying would lessen the interference like receiving calls and text messages while on flight. In addition, it is not necessary to put your device in Airplane mode but please make sure there is no such calls/text message or any notification that will interrupt you when using your device while flying your DJI Drone. Thank you and have a safe flight always.

Thank you DJI Steve, With regards to the phone I use whilst flying, it is a phone that i use specifically for flying my drone, and this particular phone no one has this number so i do not receive calls or messages on this phone, however, i do have data on this phone as i do like to use the intergrated map in Hybrid mode via mapbox, I would also like to point out that i have a secondary Remote Controller and this controller is brand new and this new controller suffers from the same issue, i.e. if i use the connected phone with airplane mode disabled i get repeated disconnects between the RC and Drone, however, if i used this same controller with the mobile device in airplane mode i have no issues in 1 hour and 20 minutes of flight, as stated in this post this confirms that this issue is down to software within the DJI Go 4 app, something about the network this app don't like.

This bug needs fixing and hope no one loses their drone because of this issue.

Carl

Fantomgep Posted at 9-2 02:26
Exactly the same issue here. I have 3 types of drones, which use the djigo4 app. The issue comes only on the M2P. I have never experienced this with my Air1 or my Spark (OTG connected). I think this  is a Sw bug, which is releated to the Mavic2 series. I have no issue with the djifly app using the same phone (Samsung Note8) with the  Mini and Air2.  I use the original DJIGO app also with Phantom3 series with zero issue.

I also have a mavic Air 1 and this issue does not happen with that drone using the same DGI Go 4 app, could be firmware on the actual Remote Controller of the M2P that has a bug in the code, either way it needs to be rectified before someone loses there drone to this, and if they do will DJI step up and compensate for the loss?.

Carl

Have you tried connecting the phone to the remote using the bottom usb port, not the side one?

Carl_W Posted at 9-2 13:13
I also have a mavic Air 1 and this issue does not happen with that drone using the same DGI Go 4 app, could be firmware on the actual Remote Controller of the M2P that has a bug in the code, either way it needs to be rectified before someone loses there drone to this, and if they do will DJI step up and compensate for the loss?.

Carl

I think you're ignoring the phone - id' guess the usb stack or network stack in the phone's os is the driver (LOL - a pun).  If the issue was in go4 or the controller firmware we'd see more widespread issues.  I know that the android version has added complexity with the back and forth charging and my guess is that particular phone has some cheap parts, or something wrong.

Also, your profile pic is awesome.

Carl_W Posted at 9-2 13:08
Thank you DJI Steve, With regards to the phone I use whilst flying, it is a phone that i use specifically for flying my drone, and this particular phone no one has this number so i do not receive calls or messages on this phone, however, i do have data on this phone as i do like to use the intergrated map in Hybrid mode via mapbox, I would also like to point out that i have a secondary Remote Controller and this controller is brand new and this new controller suffers from the same issue, i.e. if i use the connected phone with airplane mode disabled i get repeated disconnects between the RC and Drone, however, if i used this same controller with the mobile device in airplane mode i have no issues in 1 hour and 20 minutes of flight, as stated in this post this confirms that this issue is down to software within the DJI Go 4 app, something about the network this app don't like.

This bug needs fixing and hope no one loses their drone because of this issue.

Hi there Carl. Thank you for the reply and for this additional information you have shared with us. I will cascade these thread to the designated DJI department for further attention and evaluation. Again, I am sorry for the trouble this has caused and thank you for your understanding.