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Skyview autopilot caution

woodsideraff

Well Known Member
I get a continuous "caution" audible announcement when I engage the roll axis. Found out it is related to the autopilot disconnect setting in the software. The autopilot, including the disconnect function, works fine. When the disconnect monitoring feature is turned off, the A/P works fine with no caution alert. Furthermore, I get only sporadic indication of the caution alert on the display.

I talked to Dynon and they suspect an intermittent connection in the disconnect line. Has anyone experienced this situation?

Regards,

Rafael
 
I had the same problem with the Dynon D-180 and suspect a bug in their software. I disabled monitoring of the AP disconnect switch circuit.
Joe Gores
 
Same here

I had the same issue on the Skyview.
It was an intermediate "autopilot disconnect" caution.
I looked at the screen that shows when the disconnect button was pushed and everything looked good there. I even disconnected the button and nothing changed. So I turned off the autopilot disconnect monitoring function and all is good.
I still need to talk with Dynon to see why it is doing it.
 
Needs a resistor

I missed this on the autopilot disconnect. Looks like if you want it to monitor it you need to add a resistor.
Or, you can just disable the function and if it does break, you can turn off the autopilot or pull the breaker.

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I missed this on the autopilot disconnect. Looks like if you want it to monitor it you need to add a resistor.

I am pretty sure the resistor is incorporated into the AV-50000, so in the case where the disconnect button seems to be working, warnings would indicate an actual intermintent wiring issue.
 
Hmmmm

I will look into more but currently the caution goes on and off ever 1/4 - 1/2 a second (with the monitor feature on). When I look at the screen that shows the status of the button, it is solid. It shows open when not pushed and closed when pushed. No intermediate behavior. When I completely disconnect the wires it still has the caution at the same frequency as connected.
If the resistor is on one side of the wire, would it matter if the wires near the switch were reversed? I could have easily done that. I don't think it would.

I would like to know if there are any others that are experiencing the same thing.
Turn the "monitor autopilot disconnect" on in the autopilot settings, then turn the autopilot on in the hangar and see if you see a flashing caution.
 
Just wanted to pick up this old thread again as I experienced the same problem over the last few test flights. Will try the proposed fix next time I go to the aircraft.

Any other suggestions as to why the caution alert goes off when AP is engaged?

Thanks
 
I had continuous caution warnings when I operated the auto pilot.

I emailed Dynon and was told to change 'Enable broken line detect' to No.

That fixed my problems. Not sure if it will help here.

Cheers

Julian 120316
 
Resurrecting this old thread … for I too have been experiencing the “autopilot disconnect broken” warning message on the SkyView. Although I do not have a solution beyond what has been previously suggested, I did take some ohm readings to share. The warning message first appeared late November of last year … but seemingly went away after a SkyView reboot. I got the message again two weeks ago and now the “autopilot disconnect broken” warning message is constant ... unless, as mentioned by others, the AP is engaged. As a side note, the AP button on the AP Panel module, the panel mounted AP disconnect button and the pilot & co-pilot stick mounted disconnect switches all work just fine to engage/disengage the autopilot … so the wiring IS NOT intermittent.

I called Dynon about this and was told the issue is likely that my AP Panel module has a problem … so Dynon sent out a replacement. Over the weekend, I installed the replacement AP Panel module and sadly … it too does the same thing. So I reinstalled my original AP Panel module. As others have done, I just decided to get into the autopilot menu settings and selected NO for “enable broken line detect “… problem solved.

While I was at it, I decided to do a little troubleshooting of the wiring to share my results here. One of the earlier posts in this thread mentions a resistor should be used on the AP disconnect wire. Looking at the RV-12 wiring schematic, I noticed there is a 5K resistor mounted on the AV-50000A control module that goes to pin 15 of the Autopilot connector on the control module. Measured 5K at pin 15 to ground, so the resistor/internal wiring on the control module is good. The ground for the AP disconnect switch is obtained from pin 37 of the autopilot connector ... measured it and it is a solid ground.

Next, I pulled the Options connector off the control module to make sure the Y on the AP disconnect wiring was good. The other side of the Y goes to pin 9 on the Autopilot connector and is called AP Data I. The AP Data I circuit routes through the control module to pin 2 of the Options connector. If the Y and the interconnection through the control module is good, one should read around 5K from pin 2 in the Options connector on the control module to ground. I read 4.99K so there is complete continuity through the wiring. The only thing left to measure was the resistance of the AP Data I wire running from pin 2 on the Options connector to the Y, which then feeds both the roll and pitch servos. I left both the servos connected and made a ohm measurement from pin 2 on the Options connector to ground and got a reading of 25K ohms …. There must be a capacitor in the circuit because the reading started out much lower and slowly increased to the 25K ohm value …. it may actually have ended up higher, but I lost patience at 25K. Don’t know what value to expect here, but guessing this is a reasonable value.

I suspect the root of the problem resides inside the actual servos and how they report back to the SkyView. Admittedly, I did not remove any access panels to check the connectors at the servos … but since both servos engage and disconnect just fine when the buttons are pushed, the servos are obviously seeing the ground applied to the AP Data I wire running to them.
 
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You are not alone John. I went through the same steps as you had, only to disable the monitoring of the disconnect switch to fix it. I suspect Dynon has a firmware problem causing the issue, but they don't seem interested in stepping up to fixing it. Since the 5K resistor is located in the AV5000, it does not really ensure the continuity of the wire all the way to the disconnects switch anyway. It's kind of worthless in our case.
Alex
 
Since the 5K resistor is located in the AV5000, it does not really ensure the continuity of the wire all the way to the disconnects switch anyway. It's kind of worthless in our case.

Alex .... Actually, with the 5 K resistor being on the AV50000 module it insures the continuity of all the wires in the disconnect path because the disconnect originates from pin 15 which is the 5K resistor. As long as the AP disconnect wiring is intact, there will be a 5K load presented to the servos on the AP DATA I wire until the disconnect button is pushed .... at which time a solid ground will be on the wire. Should the wiring break, that 5K ohm load presented to the servos will now become an infinite resistance .... it is this change the the "enable broken line detect" should be monitoring. Without the 5K ohm resistor the servos would always see an infinite resistance (until the disconnect button is pushed) and could never detect if a wire was broken.

Here again, I suspect the method and /or hardware used for the broken line detection in the servos is not quite up to snuff.
 
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Hi John,

Please explain how the portion of the disconnect circuit between the AV5000 and the switch itself is protected by this arrangement. I guess I just don't get it.

Alex
 
John and Alex are both correct. The circuit is monitored between the resistor and the servos but not between the resistor and the disconnect switch. It would be better if the complete circuit was monitored. Regardless of where the resistor is installed, it is useless because there is a software bug that causes false alarms. The D-180 has the same problem. I disabled the alarm in mine.
Even if the resistor was connected directly across the switch where it should be, the Dynon still could not detect a defective switch.
 
Add me to the list .... phantom cautions with AP engaged. Waiting for dynon to admit it's a software / firmware problem.

Where in the settings is the disconnect monitor option ?
 
Where in the settings is the disconnect monitor option ?

Kyle -- To deselect the monitoring of the AP disconnect wire enter the Setup Menu (press buttons 7 & 8 simultaneously) then scroll down and select Autopilot Setup. When in the Autopilot setup menu change "enable broken line detect" from YES to NO.

Alex -- Joe is correct, the better place to have located the 5K ohm resistor would be directly across the switch ... it would have eliminated the need for the Y and the short piece of wire from the Y to the switch that, as Joe pointed out, isn't really being monitored.
 
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