Changed USB Module to Solve 1 Problem, and Created 2 New Ones!

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So I had a sudden and 100% persistent "DISCONNECTED" problem running my P3A after almost 1-1/2 years of flying with zero issues. Long story short, it was a bad USB Module on the controller; "DISCONNECTED" is no longer a problem (the controller again connects to my Android tablet). Same firmwares and Apps still in place - no changes there at all.

But NOW I have new big problems - never before seen with this setup - and i sure hope I can get some help.

New Issues after replacing the USB Module:
  1. Persistent "weak image signal" (100%, regardless of 1ft to 50ft proximity ranges attempted). No significant interference. No "bars" whatsoever. DO have the camera view, though it starts up a with messy green appearance.
  2. The settings show NO wifi signals - flat line - in the area on the channel page; does not matter whether Custom or Auto channel is selected - just nothing, even home wi-fi not showing at all.
  3. The firmware versions of the aircraft and controller do not show up (only the app version is indicated).
  4. The aircraft thinks it is a P3P (according to the App opening screen) and I cannot seem to drop down or scroll to change that to P3A as it should be.

The app has been uninstalled and reinstalled. the controller has its green light and does work. I've tried the mobile device with wi-fi on and off, and with airplane mode on and off (it is not data/phone enabled). As mentioned above, I have never had a whisper of a problem with any hardware or firmware until now.

Any clues about how to straighten this out???
 
I think your first and only problem always was the incompatibility between litchi and dji go, no need to change the usb module, anyway, try to reinstall the old usb module, find and app like titanium pro and freeze dji go, then try litchi. Hope this help.
 
As the USB port started working but it doesn't get the complete data, check all the three flat ribbons for their proper connection. This might get you a clue.
 
As the USB port started working but it doesn't get the complete data, check all the three flat ribbons for their proper connection. This might get you a clue.

Thank you, and @fta1964 as well. I will check and re-insert the ribbons in the morning. Can't imagine I did that wrong, but anything is possible. A true mystery.

As for Litchi mentioned above, yes that installation does coincide with things went from close-to-perfection to a pure can of worms, but DJI Go was completely turned off when that was done. MANY advised that the expensive USB replacement was necessary, though I have no clue why that worked. Litchi is completely GONE off the tablet for now, and before I changed the module.

ONE clue? may be that the new module has added features and ports, but I am assured those play no role in the current problems, though I have the original 300A controller. I have stored and treated all equipment very gently from the beginning.

Here is additional information that may play some role (much of this is "old" BUT it has worked 100% flawlessly):
  • Phantom P3 Advanced
  • Aircraft firmware 1.4.10
  • Controller firmware 1.3.20 , on GL 300A hardware, factory USB cables only.
  • The DJI GO App I use is version 2.1.0 (This is the version that brought on POI, 2K video, etc, and controller and battery update via microSD at the time; and these work really well with all modes flawless, strong signals and awesome range, etc).
  • My go to tablet is Android tablet though identical issues exist with Samsung S3 phone and iPad Mini 2 (I think the same version of DJI Go) and using different cables as well.
 
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Another thing I had noticed that whenever USB module is replaced it doesn't get fully recognized until some event is initiated. In my case FW update recognized it. There could be other ways too.
 
You can turn off dji but have several service running in background, that is way you must freeze with titanium (or other app) to stop all service or unistall dji go. In your case, better freeze to keep your old version.
 
Recheck your ribbon cables. The wide one in the rear of the module isn't hard to botch getting all the way properly inserted. That would account for only partial communication on the data path.
 
It sounds like an incompatibility between your DJIGO version and your aircraft firmware, your DJIGO is too recent.
 
It sounds like an incompatibility between your DJIGO version and your aircraft firmware, your DJIGO is too recent.
Thanks but just not possible; the version is the same I've had for many, many months, and I have not downloaded any new versions at all. It is most definitely DJI Go 2.1.0 which has performed flawlessly in the past. Have uninstalled and re-installed same identical apk.

All connectors have been verified, twice. Still have either No Signal or Weak Signal between aircraft and controller according to the App "Camera View" main page top center, and the fact it is NOT telling me battery levels, the various firmware versions etc.

Also, as suggested by @alokbhargava , I've initiated a couple of things with no good outcome (in addition to checking the ribbons). Background processes have been turned off for several of these attempts as well.

I still cannot fathom a solution, which is no doubt very simple. What is going on?!

Dare I try to re-bind the controller to the aircraft? My controller gets the green (connected) LED almost instantly after starting the aircraft, and I can control the gimbal, so I have to think it IS bound already and perfectly well.

PS: This is driving me insane.
 
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So you cannot revert at all to the old USB module ? If you could and succeed to make the whole suite work well for a while, just for testing purposes on the ground, then I would blame your old RC FW that might be partially incompatible with the new USB module.

I can understand you aren't eager to update the FWs (AC, RC, GO) because all functioned well before the USB module broke and forced you to replace it, but I would warmly suggest you should update a couple of steps fwd, say at AC FW v1.8.80 which never gave me any headache on neither of my 2 birds (P3A & P3P).
What FCC ID has your AC ?
 
What I sugest you to do, if you have a friend with a P3 try to bind his remote to your aircraft, to make sure its a remote problem and take it from there. Sometimes eventhough rarelly changing hardware modules create new problems, firmware upgrades actually upgrades different modules separatly, we had the case where changing sensor board of the camera created new failures, it was fixed with an aircraft upgrade. What is your remote model ? Is it the A version ? The A version has a texas intrument chip, and I think is not compatible with the B or C version of the USB board.
 
So you cannot revert at all to the old USB module ? If you could and succeed to make the whole suite work well for a while, just for testing purposes on the ground, then I would blame your old RC FW that might be partially incompatible with the new USB module.

I can understand you aren't eager to update the FWs (AC, RC, GO) because all functioned well before the USB module broke and forced you to replace it, but I would warmly suggest you should update a couple of steps fwd, say at AC FW v1.8.80 which never gave me any headache on neither of my 2 birds (P3A & P3P).
What FCC ID has your AC ?

I did revert the module, and got same - original - results, so back to the modern module. Weird thing is this: My wife just downloaded current DJI Go on her iPad mini 3, first time ever to use that tablet, and the stupid thing worked. We did not fly, but could see all the info was right there on the screen as it should be. The AC and Controller have not been touched FW-wise at this point. Go figure.

SO...in just a moment I shall uninstall completely the DJI Go 2.1.0 and install 3.1.4 as a FIRST step...back in a few.

Oh, yes @JogjaSkycom, it is the GL300A. There are no factory USB Modules for that available that I can find; one MUST use the upraded Part 54 with the added HDMI port, etc - but all, including DJI tech, assure me that will work.
 
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I agree that the Part 54 with the added HDMI port should work, but for example in many cases of the P4 ( I know you have a P3) , it will not work correctly unless the aircraft firmware / APP is upgraded.
 
Well...I'm HAPPY to say the first step - uninstalling all traces of DJI Go 2.1.0 and fresh installing 3.1.4 from Google Play - worked. That is, I DO NOW have a connection which is good enough to provide settings, battery charge %, etc. The firmware on the aircraft and controller remains the same as before (yes, the DJI Go App did remind me of that situation - skipped as I have in the past).

Before updating anything else, I will go out at next opportunity to a big quiet area for some tests after calibrating everything just to be sure. Hopefully all is well as-is.

Stay tuned...See ya soon - wish us luck.


I do want to thank you ALL for your comments and input - MUCH APPRECIATED!
 
Re-binding, re-linking is a no issue operation. There are no hazards doing it.
 
Re-binding, re-linking is a no issue operation. There are no hazards doing it.
Thanks - I will definitely do that because connection does not show up to be as super-strong as in the past (before the current situation); a few feet away, it should be "all bars" but it is only two or three, a short distance away.

Strangely, I cant seem to find clear instructions for relinking - is there a link to a correct instruction to re-link the AC and Controller somewhere? Can only find two different unofficial approaches when not going through the app. Which of these is right (or neither)?
  1. AC is off (which doesn't seem to make sense at all). Controller is ON. Device and App not connected. Press and hold controller buttons C1, C2, and Camera Shutter.
  2. AC in ON. Controller is ON. Device and App are connected. Press and hold C1, C2, and Video Record button.
Thanks!
 
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Phil I'm glad you've solved so easily the issue. I'm not a "let's have the latest sw update", but sometimes keeping too old sw versions becomes counter-productive, when HW changes are involved.
I thought you've replaced the old broken USB module with a same type, but you actually upgraded the RC with the Part 54 HDMI module, which is a different matter, needing the GO app update.

Here is the linking procedure of the RC with the AC, without using the GO app. Procedure applies to P3P/P3A.

1. Start the AC
AC's OFDM led will light steady red.

2. Start the RC
the left led on RC will light steady red.
AC's OFDM led will light toggling green (3x) and red (1x).

3. Press on the RC: C1+C2+Video rec buttons, then release
Hear from the RC an beep-bip-bip.

4. Immediately after the beeps on the RC, press camera setting dial, then release.
Left led on RC turns into flashing blue and repeated bip is heared.

5. On the AC, press for 2 sec the side button, near the OFDM led.

6. Left led on RC will become steady green. Beeping will stop.
OFDM led on AC will become steady green.
Linking is successfully ended.

The procedure presumes AC & RC are not yet linked. In your particular case since the 2 already form a tandem, leds @ #1 & #2 will light green.
 
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Phil I'm glad you've solved so easily the issue. I'm not a "let's have the latest sw update", but sometimes keeping too old sw versions becomes counter-productive, when HW changes are involved..... Procedure applies to P3P/P3A.

1. Start the AC
AC's OFDM led will light steady red.

2. Start the RC
the left led on RC will light steady red.
AC's OFDM led will light toggling green (3x) and red (1x).

3. Press on the RC: C1+C2+Video rec buttons, then release
Hear from the RC an beep-bip-bip.

4. Immediately after the beeps on the RC, press camera setting dial, then release.
Left led on RC turns into flashing blue and repeated bip is heared.

5. On the AC, press for 2 sec the side button, near the OFDM led.

6. Left led on RC will become steady green. Beeping will stop.
OFDM led on AC will become steady green.
Linking is successfully ended.

The procedure presumes AC & RC are not yet linked. In your particular case since the 2 already form a tandem, leds @ #1 & #2 will light green.

Wow! The info I found was apparently way off. THANK you, my friend. And, yes, I do indeed already get the green LED lights indicating a connection - as you know, it is not a "good" connection....but will be soon. Thanks again.
 
Step 2 Complete and very successful after fixing DISCONNECTED problem, using new USB/HDMI Module...
  1. Updated ONLY DJI GO (Android - Samsung Galaxy Tab Pro 8.4) from 2.1.0 to 3.1.4, keeping "old" FW's; Result - finally got view but weak image WiFi .
  2. Re-Linked AC to RC (even though showing Green on RC); Result - Now I have full WiFi bars! Did all needed settings and gimbal calibration in App. Bonus: App now knows it's a P3A. So far, so good, thanks to you folks!
  3. Calibrate compass, and fly.
Hope to get to Step 3 by tomorrow - being cautious and driving out to very large field.

****EDIT**** Will be Saturday. A few duties and obligations in the way.
 
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