P3P no video feed camera led flashing red

[edmundC]

This is how I interpret what happened:

The issue was caused by top board overheating, as it always does.
And the spontaneous fix happened because DaVinci stores backup of its firmware and sometimes (depending on which part got corrupted) it is able to restore itself to a working condition over several reboots.

Anyway, congrats on fixing your drone!

Hi Quaddamage, I'm having the same intermittent video feed problem with my P3P (i posted a thread on this) I'm learning to retrieve the Log AB file to see if I can find out more about my AC. Your interpretation about the restoration of DaVinci back up firmware makes sense to me, in this case, what is your recommendation to solve the issue?

 

[quaddamage]

You wrote in another thread that this loss of FPV happens sometimes, randomly - it would help to have the AB log from a run where you had the black screen.

If DaVinci will not respond in the AB log, then its NAND chip is likely faulty. Though sometimes you can get the same symptoms from damaged capacitor at power line.
If it is the NAND, you will have to reflow or replace it. Since issues seem to relate to temperature, there's a high chance that reflow would help.

Diagnosing bad capacitor is easy - just measure resistance at power lines.
Diagnosing DaVinci also isn't that hard - you just need USB-to-TTL converter to see its logs on a PC.

Since previously you had a working FPV at current firmware versions, it looks like this is not caused by software mismatch.

And just to make sure we're on the same page: I'm not saying the issue is at 100% within DaVinci; it likely is, hence my description; but you should confirm that in the log file.

 

[edmundC]

You wrote in another thread that this loss of FPV happens sometimes, randomly - it would help to have the AB log from a run where you had the black screen.

If DaVinci will not respond in the AB log, then its NAND chip is likely faulty. Though sometimes you can get the same symptoms from damaged capacitor at power line.
If it is the NAND, you will have to reflow or replace it. Since issues seem to relate to temperature, there's a high chance that reflow would help.

Diagnosing bad capacitor is easy - just measure resistance at power lines.
Diagnosing DaVinci also isn't that hard - you just need USB-to-TTL converter to see its logs on a PC.

Since previously you had a working FPV at current firmware versions, it looks like this is not caused by software mismatch.

And just to make sure we're on the same page: I'm not saying the issue is at 100% within DaVinci; it likely is, hence my description; but you should confirm that in the log file.

I had the AB Log when everything's fine. (Posted on my thread). So next thing I need to do is to retrieve the AB Log when there is no video feed. OK I will do it and will post the result on my thread. Sorry for hijacking this thread [emoji3]

 

[edmundC]

You wrote in another thread that this loss of FPV happens sometimes, randomly - it would help to have the AB log from a run where you had the black screen.

If DaVinci will not respond in the AB log, then its NAND chip is likely faulty. Though sometimes you can get the same symptoms from damaged capacitor at power line.
If it is the NAND, you will have to reflow or replace it. Since issues seem to relate to temperature, there's a high chance that reflow would help.

Diagnosing bad capacitor is easy - just measure resistance at power lines.
Diagnosing DaVinci also isn't that hard - you just need USB-to-TTL converter to see its logs on a PC.

Since previously you had a working FPV at current firmware versions, it looks like this is not caused by software mismatch.

And just to make sure we're on the same page: I'm not saying the issue is at 100% within DaVinci; it likely is, hence my description; but you should confirm that in the log file.

I uploaded the Log AB file in my thread here Phantom 3 Pro - Intermittent no video feed problem
Can you take a look and tell me what's wrong with my AC?

 

[edmundC]

Well the 2nd reboot after entering flight data mode worked this time. Video is back and all is normal. After that test i added the firmware .bin file back to the sd card and it didnt even try to update, all seems to be fixed and ive done a couple flights and a few reboots and the video is back every time. Could the entering flight data be the trick to resetting this all too common issue???

Hi 3rdof5, did u just enter flight data mode OR did u enter flight data mode AND download the files as well? Have you experienced any video problem since the last reboot?

 

[3rdof5]

Hi 3rdof5, did u just enter flight data mode OR did u enter flight data mode AND download the files as well? Have you experienced any video problem since the last reboot?

The first time I entered flight data mode was to copy the files (which i did). And upon rebooting my video feed was back. I rebooted again and it was gone. Once again I entered flight data mode but did not copy anything and the next reboot video feed was back. It remained working for about a month and then quit again. This time the flight data mode didnt work and I sent it to Dji for repair. I think it was just a quirky gimbal board and the reboots would sometimes work and other times not. Since getting it back from Dji it's been fine.

 

[edmundC]

The first time I entered flight data mode was to copy the files (which i did). And upon rebooting my video feed was back. I rebooted again and it was gone. Once again I entered flight data mode but did not copy anything and the next reboot video feed was back. It remained working for about a month and then quit again. This time the flight data mode didnt work and I sent it to Dji for repair. I think it was just a quirky gimbal board and the reboots would sometimes work and other times not. Since getting it back from Dji it's been fine.

Do u know what part did dji replace for you?

 

[3rdof5]

Do u know what part did dji replace for you?

According to DJI I had a bent yaw arm altho I doubt i did. They only listed the parts replaced were the yaw arm and the ribbon cable altho the entire gimbal board has a different (and non refurbished) serial number than the original board which had a refurbished serial number. I was charged for the 2 parts listed and return shipping but not for the new gimbal board. Total cost of the repair including return shipping was just under $200 Cdn. I figured they were trying to get some money outta me even tho it was under warranty and it did have one small crash from about 1 meter height so rather than argue I just paid and let em fix it. Its fine now.