Thread: Loss of GPS input to D100 and Autopilot

During a recent flight the autopilot disengaged and the Dynon display announced that it had lost GPS information. The Garmin 496 was normal. This was intermittent as it returned to normal and then lost the signal again. Yesterday the GPS information was unavailable to the autopilot and D100, while again being normal on the 496. I contacted Dynon and was told that my HS34 sends no GPS to the autopilot so the problem has to be related to the Garmin 496 output or the wiring between it, the AP, and HS34(sends GPS to D100).
Does anyone have a suggestion about how to proceed? Everything is under warranty but want to avoid down time.

Doug

Sorry I can't help you with this, but in the 600 hours I have been flying my CT I have noticed on very rare occasions (maybe 4 times total in 4 years) a temporary loss of gps signal. It typically came back after about a minute or less and one time I had to recycle the gps.

Does anyone else have similar experience?

In my case the Garmin 496 was and is unaffected. It was only the GPS out data that was intermittent at first and then out completely as it remains.
Doug

Start by checking the plugs on the back of the GPS especially if you have had it out recently. There is a blue output wire from the GPS that has a bad connection somewhere between the GPS and the other equipment. Tom

I have an intermittent problem with the HS34 losing the NAV inputs. I have both a
GPS396 and an SL30 nav-com. In the failure state, the HS34 will only show
a basic DG on the HSI display. Nav Src button has both led's off.
I get no DSAB failure alarm. HSI input setup menu shows HS34 is
set to Serial1 GPS, Serial2 SL30 but has no signal.
Pulling the EFIS breaker and resetting causes the NavSrc to operate
normally again. I'm currently at 5.0 firmware in D100 and HS34,
will try 5.1 shortly. I have no AP so I can't tell if GPS out or
HS34 in is the culprit.

What is your GPS out put setting?

My 696 is doing the same thing and it happened to me while on the way home from the dealer after delivery. It started out going off intermittently, then "NO GPS" was on the screen of the AP, then I lost the TRK/HDG mode.I now have nothing but a wing leveler and altitude hold mode. The GPS is fine but just won't talk to the AP. Also, I've lost winds aloft on the Dynon. I can live with it until I take it back for its 25 hrs checkup. I wish it was just a wire, then I could do it myself, but I think it's something more insidious than that. Let me know if you find something simple to look for.

John

your dynon cannot compute winds aloft without gps data

I few guys on the Dynon website forum have had the same issues. You might take a look and see what they found out.

http://www.theregister.co.uk/2009/05/21 ... s_failure/

Mabe this has something to do with it i have had a few problems with my 496 losing signal this year previously never ever had lost signal ...

Cheers Mike