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920+ start up problems after power distribution board change.

RTH

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Hi Folks,



I’ve just changed out the power supply board on a 920+ & the machine won’t start when I’m pressing the red start button, has anyone had any similar issues?



The board I was removing had one burnt out esc, and that motor wouldn’t spin (obviously) but all other motors would start up fine.

I got a new replacement 920+ board from an eBay seller and was very methodical in labelling each motor control cable plug into the flight controller and transferring the same sequence into the new board. Everything seems like was plugged back in exactly the same.



When I fire up the ST16 it binds just fine with the 920+ and both get good satellites.

The 920+ looks like it should be ready to take off. (For the moment I just want to fire up the motors to verify that they are spinning in the correct directions.)



The led is working, it reacts correctly when for example switching between safe,andgle, and home modes. The rear door is closed, full sats on both ST16 & controller, no error messages of any kind – compass or GPS.

At this stage when I hold down the red button, I expect the machine to spin up the motors into an idle. – Nothing happens, its as if I am not pressing the button.



I’ve checked the on the button function test screen on the ST16 and all buttons are responding correctly.



I’m stumped as to what to try next, does anyone have any ideas.
 
I would check the flight logs, especially the status values.
Is there something like the GUI for the 920+ ? Anyone knows?

br HE
Yes, there is a windows GUI for the 920+, it's effectively the same as a scaled up 480.
(but I'm on a mac so it's a real pain to get it running)

On booting it up again, it's now giving a 5 motor error, so I know where to start looking, thanks.
 
Without propellers, a 5-motors error is a normal behavior.
 
Without propellers, a 5-motors error is a normal behavior.
It has six props, the motors will also spin up without any props.
edit, I mean in general they will spin up without any props, but at the moment they won't spin at all.
 
Can anyone confirm the numbering sequence of the motors around the drone?
On the flight controller the are marked M1 through M8, (M1-to M6 in use).

I'd like to know how these numbers relate to the positioning of each motor, I'd like to know which is at 1 o'clock , 3 o'clock etc.
 
Check the power from the battery to the board. You probably have power only to the avionics.
 
Check the power from the battery to the board. You probably have power only to the avionics.
Thanks, there is power, the power to the board is by a 6 huge soldered connections, they are all solid, its now only one motor that's showing up as a motor failure, see my above post after a reboot.
I'm in the process of checking continuity but I'd like to know which plug is for which motor.
 
In other words I am trying to confirm if this is correct or not, I believe I saw this scheme somewhere before but can't rememberIMG_2345a.jpg
 
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and would anyone know what this blue LED is? Its teh only blue LED on the board and by the motor/esc that the controller is showing as a failureIMG_2346.jpeg
 
Can anyone confirm the numbering sequence of the motors around the drone?
On the flight controller the are marked M1 through M8, (M1-to M6 in use).

I'd like to know how these numbers relate to the positioning of each motor, I'd like to know which is at 1 o'clock , 3 o'clock etc.
See this post
Post in thread 'H920+ Service/Repair Manual'
H920+ Service/Repair Manual
 
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See this post
Post in thread 'H920+ Service/Repair Manual'
H920+ Service/Repair Manual
Thanks, I can now see that since I swapped the ESC board that motor 6 is the one indicated on the ST16 as a motor failure. This motor/esc had been working before I swapped the board out.
The motor & ESC that had burnt out on the old board was motor 4 and that now doesn't show any error.

Any idea on what else to try would be great, at the moment I've just stripped it down to check all connections.
 
Typhoon H has fuses for each ESC on the back of the mainboard. I do not know if H920 has the same but it is worth to check.
View attachment 28317
br HE
Thanks, all that is really on the back of the board are mosfets. The fuses and most other parts are on top.
Here's a photo of the bottom side and why I was changing out the board.

I'm back to a situation where everything looks correct, GPS good, no errors, etc and that all I need to do is hold down the red start up button to start the motors, but when I try nothing happens, it's as if the button is not working...only that it is working I can see it is on the button function check screen, I know the controller is sending commands as I can see the status light change when I flick between fight modes.

IMG_1438.jpeg
 
(You can use one output from the FC to check all the motors one by one. In this way, you can be sure about the workability of every ESC.)

Corrected. You can't use my proposal if you can't start the motors. How do you get e five-motors error if you still didn't start them?
 
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You can use one output from the FC to check all the motors one by one. In this way, you can be sure about the workability of every ESC.
With the board powered off I was trying to check continuity between each pin on the end of each motor signal cable through to each motor plug but got nothing on any of them. To do it with the board powered on I'd really like to have an exact procedure to do it, test from x to y.
 
No way to do this, as you expected. There is no straight line to check continuity at all. The topic goes into deep chaos. My proposal is to put back the board with the defective ESC to see still all the rest is working.
 
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