No GPS signal - Hardware or Software Issue?

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Thanks to DJI and the forced update of their app to 3.1.3, I now have a P3p that doesn't lock onto a single satellite! Story goes as such...

After upgrading both android devices to the new 3.1.3, I was not able to get my remote to communicate with my RC for a few days. After much pain and unwillingness to upgrade, I updated everything to the newest FW - This got me up and flying again
RC 1.8
AC 1.10.009
App 3.1.3

However, the video signal was complete garbage from what I was used to on my previous setup.
RC 1.03.0020
AC 1.06.0040
App 2.9.1

With 15-17 satellites, per usual, I was testing a waypoint route in Litchi to determine if I could use it to get better distance. I would hardly be 300ft away in an open field and it would tear and freeze so badly I had to land because the FPV was unusable. I changed from F mode to P mid air to cancel the Litchi route and regain manual control and land. After force quitting Litchi and attempting a quick change over to the DJI Go app to try a Custom channel (the Litchi selection wouldn't work), I attempt to try another flight...To my surprise I had 0 satellites in both apps (Litchi, Go) and on both Android devices! After I had landed, until now I have had 0 satellites.

I am still stuck with no GPS signal regardless of what FW version RC, AC, device, or App I have (I downgraded each with no results), which leads me to believe that I have a hardware issue. However, this all happened because I switched apps and/or flipped the switch on my RC, so I haven't ruled out software yet either.
I have logs from my updates that I can share if they will provide helpful information
Currently at:
RC 1.6
AC 1.9.6
App 2.6.1

Before I crack open my bird, my questions are:
Is GPS signal received from both the AC and RC, or just AC?
Would there be a setting or something that can shut off GPS entirely?
 
I dont believe your GPS signal problem caused by DJI GO app.
GPS is only in the aircraft, RC have no GPS. RC relies on the connected phone/tab for positioning.
Have you tried IMU calilbration? If you didnt the I strongly sugges you do. Always do IMU calibration after FW upgrade.

As per video link problem, I experienced that when I was using P4 on 1.6 RC firmware. I use Samsung Note 4 in pair. I downgraded my RC firmware to 1.5 and video link was good again. This is a known problem (for P4 for your note) and has been posted here.
I sold my P4 and use P3P exclusively and never had any video link issue whatsoever in any firmware.
 
Thanks for the reply!

I thought that was the case with gps only being in the Aircraft....

IMU calibrated, no dice

I'll downgrade my controller to 1.5 for the video feed as suggested, as 1.6 is better it's still not what I had previously.

I don't think the GPS issue was caused by the app, but it set off the chain of events by forcing me to update... which is why I never updated to begin with because it worked perfectly.

I just need to sort out the GPS and I'm sure it will be back to "normal"

Are you suggesting that it's simply an issue with the aircraft receiving signal? Which would mean broken connection somewhere...
 
This might be obvious, but just to be sure, have you check that your phone/tablet able to lock position?

Anyway I am no hardware wizz and only been flying recently, so might be off with my hunch.
The fact that you have GPS and video link problem at about the same time can also suggest that something is not right in your bird's internal.
Moreover you said that you calibrated your IMU, and tried to downgrade to various FW that suggest you tried this over different weather condition. I live in the equator (Indonesia) and in the worst weather, completely black sky the bird can still lock to 11-13 sat from the normal 17-20.

Lets hope someone more knowledgeable can give you further insight.

Edited:
just remember an incident few days back. I put on new battery to the bird and DJI GO warned me about battery firmware need upgrading. I dismissed the warning and fly to test the battery. The bird was flying erratically out of any explanation.
I upgraded battery firmware and everything is gold now. However at the time bird's still able to lock normal amount of sat.
Just sharing..
 
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I'll downgrade my controller to 1.5 for the video feed as suggested, as 1.6 is better it's still not what I had previously.
FYI that if you downgrade your RC to 1.5 (old encryption) you will also then need to downgrade your AC to 1.7 or earlier so that it also has the old encryption.
AC FW 1.8 and RC FW 1.6 were released together with an encryption change. If you have one (or later), you must have the other (or later) or you will have issues.
 
Thank you Oso! You guys are very helpful on this forum
I had read that in another thread...I like to do my homework before asking questions that have already been answered, unlike others out there ;)

So today I was skimming my FW Logs and found this when upgrading to the aircraft from 1.8.8 to 1.10.9.
[00015197][11 01][00] v1.7.15.1 -> v2.0.0.33, firmware v1.7.15.1 not support.
[00015252][11 01][00] v1.7.15.1 -> v2.0.0.33

[00013406][11 01][00] v1.7.15.1 -> v2.0.0.33, firmware v1.7.15.1 not support.
[00013450][11 01][00] v1.7.15.1 -> v2.0.0.33

I know I forgot to upgrade to 1.9.6 first. Could this be the cause?

To fix, I downgraded from 1.10.9 to 1.9.6 and still have this...

[00015198][11 01][00] v1.8.0.0 -> v2.0.0.33, firmware v1.8.0.0 not support.
[00013771][11 01][00] v1.8.0.0 -> v2.0.0.33, firmware v1.8.0.0 not support.

This is getting into deep territory, and I'm not sure how to interpret these modules/packets...any suggestions?

Added logs...
 

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Opened up the aircraft and found the gps connector loose and pads ripped from the board [emoji25]

Looks like I need to order a new board (part 33) that corresponds with my older 2312 motors....

Any recommended steps for breaking in a new board?
 
I bought it used from my work, it was repaired at DJI previously...
Under my ownership I crashed it twice, both from 15 ft or less and it worked flawlessly until recently.

The last flight I took had terrible signal issues and skipped around on landing and then, Boom! No GPS signal. . .

When opening, it seemed like a capacitor next to the gps connector was also bent pretty good. . .I seriously doubt my crashes did such damage and it seems like DJI may have reused the board from the crash that had totaled it pre-purchase

Out of warranty so I'm in my own anyways!
Good thing I know how to solder
 

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