Mavic Mini doesn´t boot correctly / no gimbal check

[Quadbee]

Hi,

I bought a defective Mini with a strange error. The seller said that it could have been in contact with water in a bag. From the outside and the inside the bird looks normal. All ribbon cables are tight and glued.

Here are the symptoms:

- When the drone is off and you push the power button only a short time (for checking the battery status) the 1st and the 4th LEDs are shining and the status LED is blinking green 5 times

- When you try to switch on the drone the initial melody plays and the motors are checked. All motors are moving a little bit but no gimbal movement takes place. The status LED flashes red 12 times and than green. After that the system seems to reboot. The melody plays and the motors are checked again. During the whole power on process the first and the 4th LEDs are on.

- The drone can be reached via USB and I tried to update the firmware. The process seems to run normal but at 39% of the update process of the drone seems to restart and same behaviour as during powering up. The melody plays, the motors are moving shortly and the status LED is flashing red. The drone seem to be in the same loop like when switching on without USB connection. After 3 reboots of the drone the update got canceled by DJI Assistant. When I disconnect and reconnect the USB-Cable the system recovery process starts at 33% and stucks at 90%. One time I got a pop-up windows which said that the battery could not be updated.

- It is not possible to power off the drone. You have to diconnect the battery to get the bird to sleep.

- Another strange symptom is that the drone powers up only with a USB connection without a battery.

Has anyone an idea what this could be? Mainboard, ESC, Gimbal???

Thanks a lot for any help.

 

[Deleted member 103366]

Whilst I do not have a clue as to the source of the problem, it might be worth considering disconnecting the camera and gimbal assembly THOUGH I would wait and see if some one says that's a bad idea.
I have flown a Phantom 3 without a gimbal or camera and it seems from posts 8 & 9 of Flight without gimbal
that a mavic 2 zoom will fly without one.

 

[Quadbee]

Thanks for the hint. Perhaps I will try it the next days how the bird behaves without gimbal and cam connected.

But my assumption is a problem with the ESC because charging is not possible either.

 

[Quadbee]

It has turned out that it was a defective mainboard. I swapped it today with another one and the drone works normal.

Now I facing the problem that I got the two gimbal error messages (40011, 40021), which are well known and I´ve learned that I have to live with them, because only DJI can pair gimbal and mainboard without these errors. But the bird flys normal and thats the main thing

 

[Quadbee]

The question that I´m asking myself is how could a short contact with water cause a damage on the mainboard? From the outside it looks perfect but I guess that some components are very sensitive against minimal currents which could be transmitted over water. It was no salt water btw. Which components on the board could be the first dying under this circumstances?

Does anybody know a place where to buy used mainboards (CE) for a reasonable price in europe?

 

[PatrickFrance9040]

I made a tutorial that explains it all.
Click here