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darnold
10-13-2014, 12:35 AM
I noticed in the 5000 installation manual the serial port setting for a GTN-650 is AVTN/FADC1.

I had the GTN-650 configured as AVTN/ARNAV on my 4500 and everything worked fine. I was wondering whether I should change the configuration on the GTN as well as on the 5400 to AVTN/FADC1 (is there any advantage)?

Rob Hickman
10-13-2014, 09:25 AM
Yes, you should change it. FADC1 sends altitude data to the GTN so it can auto sequence departure procedures.

darnold
01-25-2015, 12:29 PM
Since upgrading I now get the following Message on the GTN 650 - DATA SOURCE Pressure altitude source inoperative or connection to GTN lost.

Rob Hickman
01-26-2015, 03:38 PM
You don't have the GTN650 or EFIS configured as FADC1

darnold
01-27-2015, 12:42 PM
I think I have it correct. On the EFIS I have serial port #2 function set to AVTN / FADC1 and on the GTN I have RS232 2 input set to FADC Format 1 and output set to Aviation Output 1.

On the transponder inputs/outputs I have the RS232 Config set to port 2 input Altitude Format 1 and output Off.

Rob Hickman
01-28-2015, 09:29 AM
Are you positive that the EFIS serial port #2 is wired to the GTN serial port #2? TXD and RXD?
It sounds like the TXD from the EFIS is not wired to the RXD of the GTN.

What transponder do you have and where is it wired?

I highly suspect it is not wired like you think it is or has a broken wire. Have you tried using the diagnostics menus on the GTN-650 to see what data it is getting?

Rob Hickman
01-28-2015, 09:44 AM
We had another customer with a very similar problem, after weeks he found that he had a TXD line from his transponder also connected to the TXD of the EFIS.

darnold
02-01-2015, 03:16 PM
I checkd the GTN RS232 diagnostic...I am getting a data feed..the string is ALT 00640.ALT 00640...

This would appear to be correct. When I switch back to ARNAV I no longer receive the error message.

Rob Hickman
02-02-2015, 11:32 AM
Are you running the latest software on the EFIS from our web site?

Are you sure you have the serial port on the EFIS configured for FADC1?

We have this working on lots of customer planes, including my RV-10 so something is strange with your setup.

email me pictures of the EFIS serial port configuration and GTN-650 configuration.

Rob Hickman
02-02-2015, 11:52 AM
When you switch the GTN-650 back it is no longer looking for altitude data and will not have an error.

Rob Hickman
02-02-2015, 11:54 AM
ALT 00640 is ICARUS data, I bet you actually have the GTN serial port wired to the EFIS transponder serial port that is sending ICARUS data or you have it wired to the Transponder.

darnold
02-02-2015, 04:13 PM
Have emailed several screen shots of my config to you.