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Dynon Issue

dick seiders

Well Known Member
Two weeks ago my dynon stopped telling me how much fuel was in the tank (page 1 showing from 15 gal and less). I still had the reading of page 2 so wasn't very concerned as I believe my capacitor sending unit might have failed. I checked connection on tank and it was secure, but no info on dynon page 1.
Today following a brief .5 hr flight the alarms started blaring as I shut engine down at hanger. The alarms indicated low fuel psi, and low oil psi. I was unable to shut them off, as the dynon 180 (now on backup battery power) failed to respond to my pressing the turn off (rt button). After about two minutes I managed to shut the dynon down while it was on battery power.
I thought about what might be going on, and concluded the sensors were acting up as they sometimes do. My friends standing by had no other conclusions.
I started the engine again to test for oil psi , but ran it only about 6 seconds, and received no oil psi indication. Both the oil psi and low fuel psi alarms again fired up, and this time I had no trouble turing off the dynon which jumps to battery power immediatly after turning off master. Should I have run the engine for the full 12 seconds allowed w/o oil psi? I removed spark plugs and spun prop by hand for about 15-20 sec. hoping to get some indication of oil psi, and got none. If I operate the facet pump I show about 1.8 psi on fuel.
What is going on here? I looked at EMS settings and all appear as originally set up. Any assistance greatly appreciated.
dick seiders 120093
 
Dick, coupla things... Dynon tech always says to check your main ground any time several indicators act up, especially if alarms are triggered and gauges are momentarily pegged. This would be an easy first try. You can try the Dynon Forum but I have found it pretty inactive lately.

You mention holding the right button to turn off the backup battery. Maybe the 180 is ambidextrous and I missed it in the manual, but I always shut down my battery with the far left button.

Good Luck, Jim
 
The last paragraph on page 2-2 of the FlightDEK-D180 Installation Guide describes how to test for a good ground. This test should be performed with most electrical equipment turned on.
When the D-180 is running on its backup battery power, the oil pressure will always be zero. The oil pressure sender gets its power from the master contactor and from the avionics switch. If either switch is off, there will be no oil pressure indications.
If ground and power are good, the oil pressure sensor could be bad.
Joe Gores
 
dynon issue

Jim, I was referring to shutting off the alarms with right button. Will check ground. Thanks.

Joe, thanks for the feedback. l will be at the field tomorrow to to follow thru with the ground check. Will post results following.
dick seiders 120093
 
dynon issue

Joe, Jim, interested parties et al,
Awoke at 3am today and immediatly thought about the events of yesterday during shutdown concluding that i did something wrong as opposed to failure of the sensors/dynon/etc. Upon reading Joe's comments again this am I saw the likely problem cause. To quote comment referred to:

"The oil pressure sensor gets it's power from the master contactor and from the avionics switch. If either switch is off there will be no oil pressure indications."

Now I know I should know that, but did not. During the hand spinning of prop yesterday (plugs removed from top of cyl.) no oil psi was indicated as I used battery power on Dynon and master switch on.
I am fairly certain I had master, ign. and avionics on at start up test on restart and 5 second run. I remember no oil psi showing, but may have only run the engine less than 5 seconds, or saw the 0 on the Dynon fuel remaining report (see earlier post on that).

Went to field this am and immediatly pulled top plugs again. This followed by turn on of master switch, and avionics switch. Vigorous hand spinning of prop promptly produced oil psi at 5# quickly followed by a buildup to 43# oil psi.

A check of Operating manual tells us at start to turn on master, both ign. switches followed by avionics which I usually do in that order. The engine shutdown changes that to shut off both ign. switches, avionics, and master in that order. I concluded that I shut down igns., master, then avionics. This enabled the dynon to kick in the lo psi alarms following the loss of power at master as it went over to backup battery power.

Took it up for a check ride and the RV12 is normal as it was pilot confusion on the shutdown. Thanks, Joe.

No one likes to admit they erred, and I am no exception, but I did and I want to add that perhaps other 12 drivers may not know the importance of switch sequencing on shutdown and the ensuing excitement which can occur if done improperly. So I am urging all who read this to share a reminder with others you may know who operate these very nice airplanes.

Use MIA sequence on startup, and IAM on shutdowns, and remember both master and avionics power are required to see dynon sensor speak.
dick seiders 120093
 
Thanks Dick

Good to hear that the problem was really a non-problem. Like you, I've gotten into a habit of doing things and if something interferes with that habit, who knows what happens.

I guess to keep it simple, the basic rule is that the Master is the first thing on and the last thing off. Not sure I always do that either, but I'll try to remember that!

Wayne
 
If this is the biggest mistake regarding airplanes or flying you ever make, you are doing very well.
 
D1000 startup

Went to my '12 yesterday after a long break & discovered a problem with the Dynon. When the Master is turned on, the display flashes twice with a screenful of colored vertical lines, then goes black, followed by a slow fade up of the colored lines which remain on. Operating any of the buttons or knobs on the unit makes no difference, including holding down button 1, the 'off' button. All this with a charger connected to the battery, 12.7 volts measured at the battery with a multimeter. Turned Master off. I then turned on the unit with the backup battery via button 1. The unit booted up normally, with the onscreen voltmeter showing 1.1volts. I then turned the master on, - the display brightened a little & the voltage displayed rose to 12.7 volts. Repeated all the above procedure with the battery charger disconnected, - same result. Went flying, all appeared totally normal in flight, but same symptoms were there upon trying to boot Dynon up again after landing.. So, what to do, - really do not want to send unit back to factory again, would love to hear any theories or possible solutions, ----- Cheers, DEAN..
 
Contact Dynon directly, explain symptoms, and ask their advice. They will tell you if unit is defective and needs return for service.
 
Try Dynon Forum

Alternatively you could post your question on the Dynon online forum. Your discrepancy is likely not aircraft specific, so why not access all SkyView users? Also Dynon support staff monitors the forum and may reply there.
 
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