Garmin G500 HDG LOST error message

[Dave Piehler]

Has anyone with a G500 experienced intermittent HDG LOST error messages where the heading on the PFD is X'd out and it gives an AHRS ALIGN message? There are various causes, including one supposedly addressed by a recent software update. The Nav and Strobe lights are also said to sometimes interfere with the GMU (prescription = $1 AMU or so for LED position and anti-collision lights).

I'm interested in any experiences you can share, especially if there was a definitive resolution.

[carusoam]

Welcome aboard Dave,

There is a discussion around here somewhere on a similar topic...

It may help you to put your request in the search button at the top right.

Remember to push the forums button or the search will only go through this thread.

Unfortunately I don't remember the thread details or I would have pointed you in a more direct direction...

Look for software versions or updates, and antenna issues...

Best regards,

-a-

[Dave Piehler]

Thanks for the search tip. No joy on this issue, at least with my still limited skills in this medium.

[carusoam]

See if this has anything to do with your question...

http://mooneyspace.com/topic/11899-gtn-750-650-squelch-fuel-flow/page-2?hl=%2Bgarmin+%2Bantenna#entry158087

It is a recent discussion on challenges associated with G navigators.

There have been other discussions related to antenna suppliers and installation challenges.

I am not familiar with the Garmin equipment other than their simulated panel in FS...

Best regards,

-a-

[Marauder]

Dave -- the AHRS error message you are getting looks like it pertains to the flux magnetic heading function. If the problem has been going on for a while, it could be related to the interference you are indicating (lights, etc).

I know Peter Garmin will chime in on this and I would agree, the remote sensing for heading needs to be shielded and installed correctly. If it is a recent development, it could be a problem with the unit itself.

Bill Dunn from Penn Avionics participates on this this site. Send him a PM and see if he has any suggestions.

[Dave Piehler]

That's in interesting (and depressing) thread cited above, but not on point to the issue I'm raising.

 

Marauder, you're correct that it seems to be an issue with the location of the GMU and the interplay between that unit and the other electrical devices.  The issue is intermittent, not constant.  If the problem was with the strobe wiring being grounded to the airframe (and hence pulsing the GMU with every strobe pulse) one would think the GMU would be sufficiently unhappy to malfunction any time strobes were on.  Not so.  I'm aware of one install on the Left Coast that had great problems mapping the wing to find a satisfactory GMU location.  The installer did some rewiring to get the lights down to one ground plane.  That seemed to work, but the owner eventually installed LED position and anti-collision lights anyway.  Those are said to eliminate the problem of constant interference from strobe and nav lights because they are not grounded to the airframe at the wing.  They have an isolated ground that goes back to a block in the cabin.

 

Apparently Garmin is in learning mode about this as well.  Hence my inquiry about the experience of others.  Is this something that is being commonly seen, or is it an isolated occurrence?  (I was told by my tech that one avionics shop he knows of now won't do a G500 install unless the program includes LED position and anti-collision lights.)

[Marauder]

Dave - the issue with the strobes is probably related to the energy pulse that classical strobes require to energize. What that means is that the energy pulse used to fire the strobes may not always be at the same level consistently, hence why it won't cause interference all the time.

On occasion, my plane' s strobes can be heard through the headsets. Other times I can't hear them. I think this may be the same phenomenon. If you are able to fly with them off for a while, you may be able to confirm this. Being intermittent is the sucky part of this problem. I'm sure you would rather see it broke solid, so you can figure out why.

Our friend "electricity" can produce some strange behaviors. Good luck with the troubleshooting.

[Danb]

I had similar problem in my G-1000 unit..I ended up putting Led lights out on the wing tips and it solved my problem...

[mike_elliott]

Has anyone with a G500 experienced intermittent HDG LOST error messages where the heading on the PFD is X'd out and it gives an AHRS ALIGN message? There are various causes, including one supposedly addressed by a recent software update. The Nav and Strobe lights are also said to sometimes interfere with the GMU (prescription = $1 AMU or so for LED position and anti-collision lights).

I'm interested in any experiences you can share, especially if there was a definitive resolution.

Happened once to me with my Aspen, DYL. I know its no help to you, but there is a menu selection to reset AHRS on the Aspen. Check and see if you have such a function on the G500. 

[Bill Dunn]

Wow I am surprised that people are recommending LEDs. We have actually had a lot of problems with LEDS causing more issues than normal lights.

[Bill Dunn]

I haven't personally seen this problem on any installs we have preformed. However I have never put one in a Mooney. If you are close to West Chester, PA we could take a look at it.

[Dave Piehler]

Thanks, Mike.  The AHRS resets just fine on its own.  ;-)   You'll confuse people with that DYL stuff.

 

Bill, I'm not near West Chester, but I have family there.  If I ever make an excuse to visit we'll talk. 

 

The plane just spent two days at a reputable shop to make sure all the other bases are covered.  The tech there has been in touch with the folks at Garmin, who are sometimes helpful, sometimes not.  It seems to depend who you get.  The LED suggestion came from higher in the tech support chain. 

 

On the LED front, Whelen tells me that the STC for their Orion 650 series LED position / anti-collision lights should be issued any day now.

[ArtVandelay]

Wow I am surprised that people are recommending LEDs. We have actually had a lot of problems with LEDS causing more issues than normal lights.

I've never heard of LEDs causing electrical interference, it's the power supply or switching circuitry that is the problem. What kind of problems have you seen?

[ArtVandelay]

On the LED front, Whelen tells me that the STC for their Orion 650 series LED position / anti-collision lights should be issued any day now.

They already approved, I just installed them, Whoever told you that is a bit out the loop.

[Bill Dunn]

LEDS have power supplies too,it's just built in. We have a customer that changed to LEDs in his bonanza and they gave him audio problems and some other odd issues. Just to name one.

[Dave Piehler]

I got the info on the STC status from Jeff Argersinger, Sales Manager, Aviation Lighting Products for Whelen yesterday.

[ArtVandelay]

I got the info on the STC status from Jeff Argersinger, Sales Manager, Aviation Lighting Products for Whelen yesterday.

If you download the Whelen 2014 catalog, pg 8;

FAA/TSO-C96a & TSO-C30c — approved

FAR SPEC

Exceeds FAA minimum intensity requirements

for maximum visibility and increased safety of flight

Environmentally tested and certified to RTCA/DO-160G

[Dave Piehler]

I'm no IA, nor do I play one on TV, nor did I stay at a Holiday Inn last night.  That's why I went right to Whelen to ask a direct question about the STC .  I got a direct answer.  As I understand it the TSO does not equate to an STC for a particular model.  It is possible to have an install approved without an STC via a field approval and a 337.  I wonder if that's what you have.  The practical effect is the same -- you have a great light setup that generates less heat, has a longer life expectancy and draws far less current, giving your electrical system a break.

[Bill Dunn]

Dave is correct, just because something is TSO does not mean it is STC approved.

[ArtVandelay]

Dave is correct, just because something is TSO does not mean it is STC approved.

Ok, then the obvious ? is what does all this mean?

 Approvals: FAA TSO-C96a, TSO-C30c Types I & III, E-TSO

[Bill Dunn]

I have no idea. I only know that they are different because the Feds gigged our shop on it.

I believe the difference is a TSO is the FAA approving the data or part and the STC is the approval to put it in a type certificated aircraft. An experimental aircraft doesn't require something to have an STC because they are not type certificated aircraft.

If you want to know more PM me and I will do some more research.

[JaredDavis]

Dave,

 

I bet you already know these links. Just in case.

 

https://www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/safo/all_safos/media/2014/SAFO14004.pdf

 

And article:

 

http://www.flyingmag.com/avionics-gear/instrumentaccessories/garmin-outlines-fix-g1000-display-loss

[Dave Piehler]

Uh, sure.  But thanks for posting them.

 

Interesting in that at least one symptom is consistent, but the causal conditions referred to (moving within 10 secs or magnetic interference source nearby within 60 secs.) don't fit.  Sounds like there might be multifactorial issues here.

[Bill Dunn]

I talked to my manager this morning about your issue and he has seen it before. He said it could be something as easy as a wire routing issue. So I would recommend having that checked first before you buy new equipment.