AXP322 losing mode

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   Hi Folks,
I recently bought a plane with an AXP322 controlled by an IFD540.  The first few times I flew it everything worked as expected,  however recently I started hearing from ATC that they weren't receiving altitude.   When I looked down lo and behold it was in On mode instead of Alt.  I'd reset it to Alt and it would be good until the next flight and then the same thing.   On the ground it shows Ground mode but when I takeoff it automatically switches to On instead of Alt. 

I contacted tech support and they said it should switch to the last flight mode on takeoff.  Mine does not, it always goes to On regardless of what was previously set.  Tech support said my unit needed repair,  but I struggle to understand how this could be a hardware problem.   Before I ground my plane and spend a bunch of money has anyone else run into this?

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Rallylancer122 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 04 Sep 2020 Location: Oconto, WI Status: Offline Points: 20	Post Options Post Reply Quote Rallylancer122 Report Post Thanks(0) Quote Reply Topic: AXP322 losing mode Posted: 08 Sep 2020 at 7:19pm
	Hi Folks, I recently bought a plane with an AXP322 controlled by an IFD540. The first few times I flew it everything worked as expected, however recently I started hearing from ATC that they weren't receiving altitude. When I looked down lo and behold it was in On mode instead of Alt. I'd reset it to Alt and it would be good until the next flight and then the same thing. On the ground it shows Ground mode but when I takeoff it automatically switches to On instead of Alt. I contacted tech support and they said it should switch to the last flight mode on takeoff. Mine does not, it always goes to On regardless of what was previously set. Tech support said my unit needed repair, but I struggle to understand how this could be a hardware problem. Before I ground my plane and spend a bunch of money has anyone else run into this?

AviSteve Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 12 Feb 2018 Location: Melbourne, FL Status: Offline Points: 2249	Post Options Post Reply Quote AviSteve Report Post Thanks(0) Quote Reply Posted: 10 Sep 2020 at 1:34pm
	It could be a simple as a setting. On the other hand, if a wire is missing, then you will have to take it in. First, go into Maintenance Mode and check the Remote Xpdr settings. The Squat Input should be set to "Avidyne". Then verify that the A/C Speed setting is appropriate for your airplane. If those two are set correctly, the IFD will command the AXP322 to go to "ALT" mode when the speed goes above some threshold (which varies with the A/C Speed setting). If that still doesn't work, you may have a missing wire. The IFD WOW (Weight On Wheels) output needs to be wired into the AXP322 Squat input. You'll need the wiring diagram and/or the shop to check/fix that.
	Steve Lindsley Avidyne Engineering

Rallylancer122 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 04 Sep 2020 Location: Oconto, WI Status: Offline Points: 20	Post Options Post Reply Quote Rallylancer122 Report Post Thanks(0) Quote Reply Posted: 16 Sep 2020 at 9:05pm
	Hi Steve, The squat input was incorrect, so I changed it per your instructions. Flew it tonight and it works as should. Not sure why it worked before and then stopped, but oh well. Thanks!

yce Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 25 Jan 2017 Location: PA Status: Offline Points: 23	Post Options Post Reply Quote yce Report Post Thanks(0) Quote Reply Posted: 17 Sep 2020 at 7:40am
	Sounds like this should be a KB article for tech support. it's a good thing you questioned their response and didn't send it in for a non-repair!