Black Screen Error - Bringing back the Mavic Pro to Life

[Usman]

UPDATE on 12/06/2018 (post #12):

Problem:

1) The camera preview on the phone is totally black, i tried recording video and it comes out black as well.

2) Vertical and front sensors seems to be not working, the drone doesn't lands smoothly instead keeps coming down on full speed.

Looking forward to the help and suggestions!
________________________________________________________

folks, as most of you would know that i recently lost my mavic pro in a thunderstorm & then found by the help of a respective member here.

The drone landed in the fields that were full of mud, i believe when it landed it was heavily raining as well.

This is the condition when we found it:



Closer look to the condition, it is undamaged externally, no damage to propellers, arms or gimbal etc.



When i took out the battery, this was the condition:



Upon seeing this, i thought i should open the base as well to check the condition inside, well here is the base:



The board:



This looked pretty heart wrenching, i safely unscrewed the board and there was a full layer of mud on the other side as well (don't have the picture)

Had been pretty depressed seeing this and am not really sure if this could still survive, there was no other option but to clean it with "Water" (please don't bash me for doing so), took some brushes and started cleaning it carefully which took several hours.

Here's how it looks now:

(I have got the thermal paste to put on the board)



Now when i washed it from the water, i read somewhere that the PCB's should not be washed with the water in fact they should be cleaned with the CTC as water includes salt that can cause issues for the PCB's. So i cleaned the board with the CTC again today hoping if there are any water minerals, they could be wiped off - (hope this makes sense)

I'm letting the drone itself and the board dry on there own for like 2-3 days and would assemble them back to test if it actually survived, praying meanwhile (wish me luck please)

Until then, any suggestions, further do's and don'ts?

 

[Harrier]

So folks, as most of you would know that i recently lost my mavic pro in a thunderstorm & then found by the help of a respective member here.

The drone landed in the fields that were full of mud, i believe when it landed it was heavily raining as well.

This is the condition when we found it:

View attachment 39720

Closer look to the condition, it is undamaged externally, no damage to propellers, arms or gimbal etc.

View attachment 39721

When i took out the battery, this was the condition:

View attachment 39722

Upon seeing this, i thought i should open the base as well to check the condition inside, well here is the base:

View attachment 39723

The board:

View attachment 39724

This looked pretty heart wrenching, i safely unscrewed the board and there was a full layer of mud on the other side as well (don't have the picture)

Had been pretty depressed seeing this and am not really sure if this could still survive, there was no other option but to clean it with "Water" (please don't bash me for doing so), took some brushes and started cleaning it carefully which took several hours.

Here's how it looks now:

View attachment 39725 View attachment 39726 View attachment 39727 (I have got the thermal paste to put on the board)

View attachment 39728

Now when i washed it from the water, i read somewhere that the PCB's should not be washed with the water in fact they should be cleaned with the CTC as water includes salt that can cause issues for the PCB's. So i cleaned the board with the CTC again today hoping if there are any water minerals, they could be wiped off - (hope this makes sense)

I'm letting the drone itself and the board dry on there own for like 2-3 days and would assemble them back to test if it actually survived, praying meanwhile (wish me luck please)

Until then, any suggestions, further do's and don'ts?

Looks like you did a goog job cleaning that mess up. I may have tried some compressed air to get out some of the debris from those nooks and crannies that can't be reached? Otherwise I'm betting you will be back in the air before the weekend is over!

 

[BD0G]

Mineral oil - Like baby oil is better for pcb cleaning. One can actually run electronics submerged in mineral oil. Its not good to get it on sensor openings and the like , but for printed circuit boards its better than water. Or if you have to use water then Distilled water should be used as all of the suspended metals and minerals are removed.

 

[Robert Mitchell]

Good Job! Now you can only hope that the battery was dead before any contamination got in and damaged energized components.

I had an octocopter go down in a lake once. Was on the bottom for 5 days. I was able to retrieve it and revive it and it still flies to this day. Only thing that saved, IMO, it was that the battery ejected on impact

 

[Mossiback]

You will also need to clean your gimbal without getting anything inside the camera and set up a fan to get some vigorous air movement on it.

NOTE: Giving credit where credit is due, you got it back thanks to the unselfish efforts of @sar104 .

 

[Mossiback]

Don't forget the motors.

 

[Usman]

Guys, i was going to assemble the drone today, plugged the battery for charging but LED no.1 (not the one close to the button) keeps on blinking continuously, can anyone tell what could be the possible issue and how to sort it?

 

[Usman]

UPDATE: Battery successfully charged, drone assembled.

It gives 2 errors:

1) "Aircraft Motor Overloaded. Check whether gimbal clamp is removed" - Gimbal clamp is removed.
2) Gimbal is restarting. Check that the gimbal rotates smoothly if restart fails again.

Now the issue is, the gimbal seems totally stiff, if i try to move it from my fingers, i does not move nor the camera shows result in DJI app.
Secondly, i thought to give a test flight but was scared to fly it outdoor so i picked the drone in hand and did auto take off but it seems the motor RPM got too high, it was over 9000 in normal as well as sports mode, i tried 3 times but stopped it within seconds.

I have uploaded the logs as well if they could help tracing out the problem:

DJI Flight Log Viewer - PhantomHelp.com

DJI Flight Log Viewer - PhantomHelp.com

DJI Flight Log Viewer - PhantomHelp.com

Any leads?

I'm still afraid to test it outdoor or shall i go ahead?

 

[Mossiback]

Guys, i was going to assemble the drone today, plugged the battery for charging but LED no.1 (not the one close to the button) keeps on blinking continuously, can anyone tell what could be the possible issue and how to sort it?

From pages 29 and 30 of the manual:

 

[Mossiback]

...Now the issue is, the gimbal seems totally stiff, if i try to move it from my fingers...

The same sludge that was on everything else was also on/in the gimbal fittings.
I can only guess about the rest of your problems, so I won't.

 

[BD0G]

You have "sludged up" your gimbal motors. Consider purchasing an entire gimbal replacement and replacing the one that you have on the Mavic. @Thunderdrones can supply you with the part(s) if you are mechanically inclined.

Thunderdrones Parts for Mavic for sale

 

[Usman]

The same sludge that was on everything else was also on/in the gimbal fittings.
I can only guess about the rest of your problems, so I won't.

The gimbal works well now, there was debris in it which was heating the gimbal and giving overloaded error.

Did a 2mins test flight yesterday, motors, boards etc seems to be working fine, what i noticed is the vertical and obstacle sensors are not working and the camera video is black on phone, any leads to these problems now?

 

[Usman]

Can anyone help with the black screen / no image issue? Even if i record the video it comes up all black.

 

[Paul2660]

Odds are the actual sensor was damaged.

I would consider a new camera/gimbal.

Again I would consider Thunderdronesp both for parts or the repair.

No way to clean the sensor. You have the drone back to flight ready which is amazing.

Paul C

 

[Patmaherjfm]

I realise this a old thread, but for the sake of anybody having the same issue, black video+ obstacle and landing sensor not working. I would suggest the board at the front that all of these plug into is either not getting power, or is faulty. I replace the from left sensor and forgot to plug the power lead in and got that problem, hope this helps someone.