Garmin autopilot issue

[Captain_John]

Walt, use of installed equipment needs to be evaluated. If the installed equipment isn't functioning, it can't be evaluated. I have the LOD with the reason on it to show you if you still find it strange. Trust me, it's a thing!

Thanks for your input though!

On a different note, I did look at my data and in the Autopilot State column it has two strange lines of code. If anyone knows what Fail/abnormal disengage/00000004 and Fail/communication fault/00000005 means, I would be interested in knowing.

Steve from Garmin, the data is in your inbox.

Thanks again!

CJ

[SMO]

I would suspect the CAN bus. I had a similar intermittent problem. I ended up redoing all the connections - I found one connection where I had sliced into one of the wires when stripping the outer sheath, and one of the fine wires from the shield was shorting there.

[Dugaru]

Originally Posted by Captain_John

Yesterday in the final throws of my IFR checkride, during the flight portion (of course) of the test my ap disconnects. I presumed that I hit the trim buttons, so I re-engaged it. After about a couple of minutes it disengages again. This happened several more times and I was unable to complete the exam. As you can imagine, this was somewhat discouraging!

I was the guy who started this thread about the servo issue. What you describe does not sound like my servo problem, which annunicated with a big black box on the screen.

It does, however, sound like the problem I had just a few weeks ago, after my autopilot had been working correctly for months:

http://www.vansairforce.com/communit...d.php?t=161284

Did you also get a red "AFCS" failure alert?

I've been logging data religiously since my incident but thus far it's been working without a hitch. I'll be interested to see what you come up with.

[Captain_John]

Well, I got no indication of any failures. No red x's or anything. It just bugged out with the trlple tone.

I will keep you posted with what I discover.

Really looking forward to getting this sorted out!

CJ

[Dugaru]

Originally Posted by Captain_John

On a different note, I did look at my data and in the Autopilot State column it has two strange lines of code. If anyone knows what Fail/abnormal disengage/00000004 and Fail/communication fault/00000005 means, I would be interested in knowing.

Your error message seems to be similar to what was described in this thread:

http://www.vansairforce.com/communit...d.php?t=157633

So maybe there is a new software problem. On the other hand, I'm running mine from a G5 with a GMC307 panel, so there are a lot of variables that are different between yours and mine. Who knows.

I was able to get mine going again after popping the autopilot circuit breaker and resetting it, and it worked after that, but I haven't been able to fly it much lately.

I am envious of your triple tone! I would love to have an audio warning of the autopilot disconnecting. I get only a little flashing yellow square (and sometimes the AFCS warning) on an attitude indicator that is my backup AI, so an uncommanded disconnect is easy to miss, especially in cruise. I think this is a drawback of a G5/GMC307 installation that appears to have been remedied with the GMC507.

Garmin folks: is there an upgrade path from the 307 to the 507? I think the warning tone would be worth it, although obviously it would need some additional wiring to the audio panel. Or could you do a software upgrade that flashes the whole G5 screen yellow (or something similarly "alarming") when the autopilot disconnects?