Now I had the update installed last week, and the first two flights have resulted in the same problem.Yesterday,  I waited over five minutes while the engine warmed up, and still NO GPS. Again, after restarting, it picked it up. And it held them during the flight.

 

What's up with this? Is is something in the software? Why do I have to restart the unit to capture GPS?

 

Very frustrated at this point.

 

 

 

How do I get the datalogs?

 

 

 

I guess it bothers me more than anything that Avidyne doesn't recognize that it has had an issue.

FWIW, it's not clear to me that these are all the same issue, or that there's any systemic fault here.

* Orest

 

 

The first flight with my unit, the GPS failed.  It never reacquired again, temps and software were no longer reporting for the GPS or LIO items.  I put about 800 nmi on the unit with it never acquiring before I had a chance to RMA the unit.  Hardware needed to be replaced.  Back from rework, the unit was recently reinstalled and the GPS failed on the first flight just prior to the FAF.  The GPS never reacquired the entire flight home (~25 min).  Back on the ground while on the phone with tech support, it was able to acquire, but lost it again after a few minutes.

Can you follow my statement now?

I believe these continued issues are a result of Avidyne not recognizing it has a larger reliability issue than patching a few software bugs.

I've been quiet about the issues I've been having until now, but the second failure straight out of the box is simply unacceptable.

Your GPS failure mode seems unique compared to those that have been described here. Different than mine as well.

When was the "second" unit shipped to you? From what I understand there were at least a couple things going on, some software, some hardware. Apparently it only affected a small subset of folks, typically the 14v folks, I was one too.

My current unit is absolutely solid, everything is working as it should be. If your unit is not working, then RMA it back. They'll swap it out in generally a few days.

Any chance you have an antenna issue?

* Orest

I just received my unit back from RMA on Tuesday (3/31/2015).  My two GPS failures are unique from each other, not sure if they are similar to what other people ran into.

I have a 28V system.

The logs have already been sent to tech support, but it's after hours there (and now the weekend) and I'm supposed to fly to the coast in the morning - I hope the VFR forecast is accurate.  Next weekend up in the Bay area has me more concerned.

* Orest

On today's flight, the GPS was working for the first 45 minutes before it died.  When it was working, I had a chance to tune in and ID a VOR, turn the CDI and watch the green line move on the 540.

When the GPS failed, although I could still hear the audio and the frequency had the blue ID box, I was not receiving VOR information on the CDI.  This is another problem for me because I was thinking that if the GPS died in flight, that at least I could still revert to an ILS, which now I cannot because the GS is tied to the 540.  I can't even use dual VOR functions so I'm down to a single VOR (of my kx-155a).

I hope this combo failure is not part of the design, and just some useful troubleshooting info.  I can't believe the FAA would allow the box to be certified with this type of failure.

Sounds to me like your experience calls for a unit swap out, doesn't it?

Absolutely does, still waiting for the AOG callback that was supposed to call back "right away" last night.

* Orest

I was thinking about this because the RMA I did was partly due to I/O issues. 

Since I didn't test the VOR on Friday and it hasn't worked again since I saw the VOR issue yesterday, I can't say that I have a valid test to say the VOR output has died.

I have a few other squawks I might as well mention to think about a little.  I wasn't too concerned about them yet since I was expecting to be able to resolve them once the unit was working properly.

- I get a recurring alert to says "selected course / dtk mismatch" while both the CDI and the HI are both set to the proper heading (dtk course and what the course that the alert says) and the CDI is in GPS mode.  Since I saw the green VOR line move on the 540 earlier, I think the CDI wires are connected properly for both input and output.  I don't see that the gyro heading indicator needs to be wired, I only see IRU / AHRS systems listed in the 540 IM, so I don't believe it's trying to read the bug on my HI.  My guess is a config issue, but I'm not sure where.

- Even while I was getting GPS signals, the FLTA inhibited would annunciate randomly and stay on for a random amount of time.  I think I noticed one instance at ~10 seconds and others over a minute.  My guess is a install or unit issue.

- EI FP-5L fuel flow is not talking with the 540.  The unit is listed in the proven interfaces table of the install manual and I have the channel input set to Arnav / Ei-fuel as shown on page 82 of the install manual.  The installer had this partially configured, but not working.  I thought that was because I had the FP-5L previously set to talk to a G296, I've reset that to what I believe should be the proper settings according to the FP-5L IM.  I believe it's In1 and Ot1, but I have my notes at the hanger.  I plan on giving Ot2 since it also states Garmin units.  My guess is an install or config issue (maybe the installer connected the wrong channel?)

- The AXP-340 does not automatically switch between GND and Auto modes, even when I had the channel output set to ADS-B (Avi) and had lat/long showing up on the transponder.  I could only cycle between ALT-ON-SBY and GND was never an option.  I'm wondering if unit defaults to squat over lat/long and the installer has it somehow wired for squat and it's continuously thinking it's flying.  My guess is a config issue.

- With the 540 set to it's maximum volume, it is still very quiet, much quieter than my kx-155a.  No idea - unit limitation?

- The AXP-340 volume is also very quiet even with it's volume set to max (I know this is another forum for this).  No idea - unit limitation?

Update: This is a new 540 install using the Avidyne tray, there was no previous 530.  FLTA and TA are both turned on for the user settings and I was in cruise at 8500 feet in the valley so there should have been any inhibiting due to being near an airport.

Haven't been able to get my fuel flow working either although it is wired and configured correctly.

Sorry to see you are having all kinds of issues.

The AXP340, in contrast, is fairly quiet at its default setting. So, I changed the audio setting to 9 I think. It is in the maintenance menu of the AXP340.

I have a PM8000B.

good luck getting this resolved.  I had my IFD540's removed and my original Garmin 530W's placed back in my turbo prop.  as soon as that happened, my Garmin G500 didn't have erroneous data coming from the ADC to determine wind speed/direction and my traffic from my skywatch performed flawlessly. 

I've gone thru 3 replacement units.  I purchased a turbo prop because I wanted the highly reliable dispatch rates.  having avionics issues that cause AOG isn't acceptable. 

I'm surprised the FAA approved this box given the number of failures I read on this forum about intermittent GPS issues.

As AviJake mentioned above, after further investigation of the logs, they believe the unit had an I/O failure and sent out a new unit.

The new unit arrived and has mostly worked.  The GPS was solid for about an hour while I was configuring the unit, changing config settings on my EI FP-5L, and verifying GPS data to my ACK E-04 ELT.  A little while later while on the phone with tech support because the transponder doesn't seem to be switching modes properly, I fired the unit back up and it no longer had GPS signal, but it would flash a few bars from time to time on the GPS page.  Previous failures would had nothing on the GPS page.

Today I flew a quick flight to test VOR reception and CDI response and most things seemed to work OK.  The transponder still isn't switching modes properly, but the fuel flow is now communicating both directions with the GPS.  I was only airborne for 25 minutes, but the GPS never failed (it worked for ~45 minutes before dying last sat so I'm not confident this means the issue is resolved).

The unit doesn't respond to the dimmer rheostat and doesn't respond reading the voltage in the calibration section.  It was working out of the box (I was able to calibrate it properly out of the box), but then it lost the settings and no longer responds to the dimmer.  The rest of the avionics still respond to the dimmer and the AXP-340 can read the dimmer voltage as a test so it seems like it's a 540 (unit or install) issue.  The prior unit was also having dimmer issues so I've been working with the installer to troubleshoot that, but neither him nor Avidyne tech support believe that the dimmer circuit would be related to I/O issues.

FYI, I think the transponder not switching modes properly is an install issue, I don't believe P1001 Pin 8 Weight on Wheels was connected properly.  Tech support had be believing that everything was connected properly because it was receiving GPS data properly, but this seems to be a separate discrete line.

I agree we are at the point where we need to determine root cause because I believe this would be the 3rd unit in a row that was determined to have I/O issues although the symptoms have been different.  Please provide some specific guidance of how to provide useful data to you for your investigation.  I'm not sure trying a 4th unit is the best idea at this point.  Finding a root cause rather than having the symptoms go away will go a long way to regaining confidence that it'll remain solid in the clouds.

By the way, we cancelled our spring break trip to visit family due to this, there is a good chance I would have needed IFR capability.

That may be true, but since it takes down GPS reception, then from the user perspective this IS a GPS failure at best and possibly a larger system failure (when it took out my VOR indications on the CDI).

I've turned the unit off in flight several times to try to reset the GPS and power cycled the avionics switch when on the ground to reset the unit.  Some times I'd turn everything off while reading the manuals and go back and test 30 minutes later.  Once it lost GPS, it lost it for the rest of the day with one exception.  One time it didn't have reception the entire flight back, but reacquired on the ground while on the phone with tech support for a few minutes, but then lost it for the rest of the day.  Just as another datapoint, my experience is that it is much more likely to stay failed even when power cycling the unit after a failure and not for just that flight.  I was thinking there was a temperature component to the issue.

I offer this as a potential pointer to whats going on, knowing full well it could be meaningless. I have an IFD540 and Aspen setup in my airplane. It is a new install of everything, no reuse. It is running 10.0.2.0 and I have not, up until yesterday seen a GPS fault on the unit in probably 20-30 hours of flying in the US and Mexico. Yesterday, when taxiing from the fuel island at KLVK to my hanger, the unit suddenly showed a GPS fault and dead reckoning. I was in a hurry due to passenger needs, so didn't check the GPS satellite status or wait to see if it would recover on its own before shutting down. What is interesting is that I used to have a GX60 MX20 combination that was rock solid except that the MX20 blue screened on me several times in the exact same location with a general system fault. I do not know why this spot was problematic for the MX20. In two years of use I never had it do this anywhere else but in that one spot, taxiing on the ground back to my hanger. Error codes are not very clear for that unit but it looked like it thought it was getting garbage GPS data and so took itself offline.

My thinking is this could be due to some sort of radio interference bleeding over into the GPS receivers and corrupting the data. This location on the airport is off to the side of the ILS glide slope antenna, but is in front of it and there could be a strong side lobe there. I know the observation of loss of GPS sticks around for the IFD540, but once confused, the receiver software may get into a state where it's not recoverable. Perhaps the failures in GPS lock are due to radio interference with the GPS receiver at startup.

I pulled the logs from the unit today in case someone is interested in looking them over. I also pulled the plane out of the hanger today and checked it. Plenty of good satellites and immediate GPS lock. Go figure.

Do you have an update or a timeline?  This is my 6th week down due to this issue with no resolution in sight.  If it's a software issue, does that mean we'll be waiting a while for 10.1.1.0?  How fast can you turn around a bug fix release?  Pretty soon I'm going to be incurring airline costs because my airplane has been downgraded to VFR due to this upgrade (I've already cancelled a few trips).  If I was a 530 upgrade, I would have that unit back in during this troubleshooting and would still have full capability.  Since I'm a new install, I'm totally stuck at this point.

We will verify the fix is a solid fix and then determine how we roll it in.

 

Great news!! I sure hope this is the bug we have all been expecting you to find and KILL!!

 

I had my 4th unit installed this week, and with only 1.5 hrs flight, everything is working well. I look forward to a long cross country and NO GPS errors!!

My airplane is all done and waiting for all-up integration test of the avionics, except that we had a failure of a non-Avidyne product and we're delayed now for a month waiting on a replacement.  I would hate to finally get that thing in and then find out that the 540 has to be shipped off...

I confirmed with TJ today that he is looking into it and gave him the new logs that you sent me.

 

In discussion with Avidyne afterwards, they believe they have the fix in 10.1. But that is what I have been told with the previous updates. I may be a fool (fool me once, shame on you; fool me twice, shame on me), but I am willing to wait it out. I do like the unit, much better than what I have seen in the G750. I just can't believe how frustrating this has been for me. I know it has worked in many installs, why my plane? We have tried multiple fixes without success. So the plan now is to go back to the 530 and wait for the update.

I went out again yesterday. I had to recycle (turn avionics master on/off) four times before the unit actively engaged any GPS signals. And then it held them for the 45 min flight. What sort of installation error would be so sporadic?  It functioned perfectly the first two hours after I got the new unit. I am replacing the 540 with the old 530, at least until the update. If it works like it did before, with no loss of signal, I would question either the 540 box, or some funky incompatibility with the tray or antenna,  I guess. And then I would say for my plane, unfortunately, the 540 was not "plug-and-play" as I had expected.

ksdoc,

I hesitate to post what we found in mine just yet because I'm not sure that I'm "done" and that we actually found the issue.  I haven't had a chance to fly it much yet to prove out the fix, but here's what we found.

I was on my 3rd unit that was malfunctioning so I didn't want to swap without finding something that was actually wrong.  The logs showed that the current unit had GPS issues prior to leaving the factory (my understanding is that they now look for that issue in the logs before delivery - I'm not sure if it was something new they found).  My unit was showing that it had antenna voltage spikes.  I wanted to come back to the dimmer circuit because all 3 units had issues with the dimmer although the installer and Avidyne had ruled that out as a separate issue.  Eventually Avidyne believed that the dimmer voltage and ground pins were reversed.  The installer found all the wiring to be correct, but that the ground pin for the dimmer was a manufactured defect.  Apparently it was just a little shorter than the rest causing intermittent connectivity.  I can see this when flying, but it's a bit curious when I was also having problems on the ground.  Regardless, the installer replaced that pin and the dimmer is now working properly (although I'm not sure I understand why the AviCurve doesn't go up to 100% brightness) so that is something that improved over the past 3 units.  I haven't had any problems with it on my flight back from the shop, but it's worked for longer periods before failing with the prior units so I need some flying hours to gain some confidence.  I also need to put some hours on it so I can send the logs to Avidyne and verify the antenna voltage spikes are gone and that they must have been due to the intermittent ground.

Maybe the 530 is less sensitive to the connection in the tray than the 540.  I'd suggest that the shop should redo the connectors on your tray.  This should all be covered under warranty so it would be a matter of your time and convenience.

 

I plan to swap out the unit today, and when 10.1 is ready, he will take a fresh look at everything during the re-install.

* Orest

I hope that the 10.1 fix is it, because this is a show stopper.  Luckily it was VFR and I had ipads and such.  

When i departed, I had the same old issue where the heading was correct, but the plane was pointing the wrong way.  This is NOT a track up vs Heading up vs north up issue.  

Very disorienting to look over at the box at 200' and see RED all over from the FLTA stuff, and the airplane pointing back at the runway vs at my heading.  

I have been very supportive, but...   My 530W is sold, and I am starting to get a bit nervous.   I am out of town and need to get home on Friday... 

My airplane goes in the shop for the second 540 install on Monday, BTW. 

Hopefully, the FAA will get off the dime and approve 10.1 SOON, and it fixes these glitches. 

Ken

Luckily, I kept my GNS430W in my panel to provide an approved WAAS signal to my GTX330ES transponder.  So I have a legal backup for IFR flight.  However, I can't couple my autopilot to the 430W.

Steve, what would you suggest we do while we wait for the software release 10.1?  The problem with my unit losing GPS lock seems to be getting worse...

Mike
< ="cosymantecnisbfw" co="cs" id="SILOBFWID" style="width: 0px; height: 0px; display: block;">

I haven't sent in my logs yet.  Should I do that and if so, to whom should I send them?

Thanks!
< ="cosymantecnisbfw" co="cs" id="SILOBFWID" style="width: 0px; height: 0px; display: block;">

Same here.  Of the dozen or so flights I've taken since my install, three or so involved at least one loss of GPS position while in flight.  Last Friday, I had the first experience of no GPS position on the ground at startup, but it had acquired by the time I taxiied for fuel and completed my runup, so it wasn't an issue.

Steve, I haven't contacted anyone at Avidyne about this because I thought all the GPS loss issues were known and being addressed, but it sounds like it'd be a good idea to go ahead and send in my logs.  Could you remind me who to send them to?

* Orest

* Orest

Inflight, usually less than a minute. Once flying a SID out of Vegas, though in VFR. On the ground recently, I have had to recycle the box 4 times before acquiring a signal.

 

 

Happily, my exchanged unit has been solid.

I go in Monday morning and spend an alarming amount of cash to have the second one installed.  So, I'll have your dealer work with you and maybe we can make some progress. 

 

Ken

There are two different settings, one is in the user settings (heading up versus track up), which you discovered. When flying, with any cross wind, you will see the plane crabbed. With heading up your plane nose will be straight up, with track up, the nose will be one way or the other and the dotted track line will be straight up. When you are on the ground, not moving, there is of course no difference between the two.

The other is switched through track (or heading) up plane centered, track (or heading) up with a 240* view, and north up. This is done by clicking the right knob in, when on the map view.

* Orest

 

I verified on my flights over the weekend and to the avionics shop on Monday, that pushing the right knob DOES in fact switch between the views.  (Duh! Operator error).    Not sure how I missed that.  I suspect, that the setup page setting is the default view (heading up or track up)? 

 

I have no more info to report about the issue (where the little airplane is NOT pointing where the ship is pointing in relation to the map.)    But, now that I know how to switch between track / heading / north, maybe I can learn something more. 

My comanche is in the shop having the old Narco Mk12D removed for the second IFD-540.   Just found out that my Shadin doesn't support output to a GPS box (no big deal).    Hopefully, 10.1 will be approved while it is still there, so that I can leave with the new software, to go with my spiffy new hardware. 

 

I feel much better about the situation with these teething pains.  My avionics shop (who has a stellar reputation) says, "Avidyne will 100% get past this and get these little issue resolved".    This is not unheard of for new products.  He pointed out that those who got a big discount to be an early adopter, may expect to suffer a bit in the begininng.    I am hopeful that 10.1 will squash this bug. 

Another case where the FAA super-oversight is a hinderance to safety. 

 

 

Ken

 

 

You still don't have that quite right.

As I note above, if you choose in the user settings HEADING UP, then when you click the bottom right knob in a map view you will select between:

heading up with plane centered; heading up in 240* view; north up with plane centered.

 

Thanks for the clarification.    I will have to study the manual again, and maybe play with the sim before I get the plane back.  With two of these boxes, I will be overwhelmed with info for a bit.  I'll need a nice long cross country to play with them in cruise.

 

Ken

Fortunately, my avionics shop was able to swap my unit for a loaner (their demo box) and send mine back to the factory for warranty service.

Hopefully I'll get it back soon and won't have this problem again.  The loaner IFD540 seems to be working just fine.

Mike
< ="cosymantecnisbfw" co="cs" id="SILOBFWID" style="width: 0px; height: 0px; display: block;">

I have an early production IFD540 (s/n M144433036). I've had GPS lock-in issues at startup which I haven't reported but I believe my serial number is a candidate for the I/O board fix. I also now have a frequent but intermittent unreadable com transmission problem that will require ship back to Avidyne for repair, according to my avionics shop.

 

Is it beneficial to send the logs in to verify the failure?