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  #1  
Old 06-06-2020, 03:52 PM
Kooshball Kooshball is offline
 
Join Date: Dec 2018
Location: NC
Posts: 163
Default GRT Sport EX display goes crazy once it sees pitot pressure???!!

I?m in the final stage of install and testing on the panel upgrade which includes an AV-30, GRT Sport EX, ADSB in/out and MGL tach / MP.

All the wiring was done this week and all units behave normally except the GRT sport EX but only once it sees pitot pressure.

I setup a leaf blower to give 45-60 kts of airspeed into the pitot tube and then and only then did the GRT display start displaying all kinds of vertical lines. When airspeed is removed the display goes back to normal.

Has anyone here encountered this? If so, what was the problem and the solution?

Pic below and I have a video as well. Thx!

https://ibb.co/hVf8rL6

<a href="https://ibb.co/hVf8rL6"><img src="https://i.ibb.co/hVf8rL6/901113-F3-F239-4-ACC-8-D30-02-CC2-FF74-BA5.jpg" alt="901113-F3-F239-4-ACC-8-D30-02-CC2-FF74-BA5" border="0"></a>

Last edited by Kooshball : 06-06-2020 at 03:59 PM. Reason: Photo
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  #2  
Old 06-06-2020, 03:58 PM
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rv8ch rv8ch is offline
 
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Default Something's wrong

Quote:
That does not look like anything I've seen before. I think you will need to call GRT Avionics on Monday.
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  #3  
Old 06-06-2020, 04:10 PM
BobTurner BobTurner is online now
 
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Well, this sounds crazy! Is it possible the pitot line is connected to a vent on the efis, or maybe the pressure sensor is broken inside, so there?s a strong blast of air pushing on a ribbon cable somewhere? I?d start by pushing some vinyl tubing over the pitot tube, tape over the drain hole. Hold the tubing in a U shape, add some water, lift up the free end. If the water in the U stays level, you?ve got a leak. Step two. Same vinyl tube over pitot, no water. Bring the free end of the tube into the cockpit, gently blow while watching the efis. Still go crazy? Can you hear air leaking anywhere?
BTW I cannot see picture.
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  #4  
Old 06-06-2020, 04:26 PM
BobTurner BobTurner is online now
 
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Now I see photo. Call grt.
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  #5  
Old 06-06-2020, 04:28 PM
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Mel Mel is online now
 
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Is your leaf blower possibly electric? Looks to me like it could be interference from a nearby electric motor.
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  #6  
Old 06-06-2020, 05:07 PM
Kooshball Kooshball is offline
 
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Quote:
Originally Posted by Mel View Post
Is your leaf blower possibly electric? Looks to me like it could be interference from a nearby electric motor.
It is and we thought of that so we switched to compressed air from a distance so as not to damage anything. The same thing happened with compressed air. (The photo was actually of the compressed air failure mode) The AV30 behavior was normal in both cases.
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  #7  
Old 06-06-2020, 05:14 PM
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Mike S Mike S is online now
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The screen is showing multiple alarms, have you looked to see what they are??

Press the "MSG" button to see what is making the little gnome inside the box unhappy. You can then inhibit each item and see if the lines go away with one of them.

Might find the issue ---- might not, but probably worth a try.
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  #8  
Old 06-06-2020, 05:18 PM
Kooshball Kooshball is offline
 
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Yes, just voltage below 12V alarm and no GPS2 signal since I had that off.

Quote:
Originally Posted by Mike S View Post
The screen is showing multiple alarms, have you looked to see what they are??

Press the "MSG" button to see what is making the little gnome inside the box unhappy. You can then inhibit each item and see if the lines go away with one of them.

Might find the issue ---- might not, but probably worth a try.
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  #9  
Old 06-06-2020, 05:42 PM
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Quote:
Originally Posted by Kooshball View Post
Yes, just voltage below 12V alarm and no GPS2 signal since I had that off.
Well, as Thomas Edison would say----at least you know a couple things that are not the problem.
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Flying as of 12/4/2010

Phase 1 done, 2/4/2011

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"Flying the airplane is more important than radioing your plight to a person on the ground incapable of understanding or doing anything about it."

Last edited by Mike S : 06-06-2020 at 05:49 PM.
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  #10  
Old 06-06-2020, 07:09 PM
BobTurner BobTurner is online now
 
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Since grt won?t be open until Monday, I?d pull it, take the cover off, and look around the airspeed sensor. Is there anything that moves? Are there any cables/connectors up against it? Gently push on the internal connectors, make sure they?re all seated.
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