GTN 650xi big red x on NAV

[toolmanmike]

New install. G3x with all the goodies. Everything seems to be talking to each other but my 650 shows message “nav/ils failed” and I have a big red x over my nav frequency. Guys at stein and I have been through everything we can think of. I have multiple emails to g3xexpert- no response yet.
Anyone had anything like this and remember what you did? I’d r3ally like to close this avionics bay up this weekend. Don’t want to do it until everything works. I’m also terrified my GTN is broken and I won’t know for sure until the warranty is no good.

Thanks
Yes, all antenna are connected.

 

[Ed_Wischmeyer]

Make sure the antennae are connected to the correct connectors, not just connected. Don’t ask me how I know…

 

[bjdecker]

Verify the A429 settings in the G3X Touch configuration menu are correct.

From my installation (G3X Touch/GAD 29/GTN 650xi) it's configured as follows:

G3X Touch - A429:

429 Output 1 - NAV 1 - EFIS/Airdata Format 2
429 Output 2 - None
429 Input 1 - NAV 1 - Garmin GPS
429 Input 2 - NAV 1 - Garmin VOR/ILS

GTN 650xi:

ARINC 429 In 1 - Low - GDU Format 2
ARINC 429 In 2 - Low - Off
ARINC 429 Out 1 - Low - Garmin 429
ARINC 429 Out 2 - Low - Off
SDI - LNAV1

GTN 650Xi is running 20.32 firmare, G3X is using 9.31

Cheers!

B

 

[mburch]

my 650 shows message “nav/ils failed” and I have a big red x over my nav frequency.

In my experience, the most common cause of this is also the simplest and easiest to check: No power/ground on the GTN NAV connector (P1004).

 

[bjdecker]

In my experience, the most common cause of this is also the simplest and easiest to check: No power/ground on the GTN NAV connector (P1004).

Expanding on this -- On P1004, verify pins 22, 49, 60, 61, 62 are connected to Ground, pins 51 and 52 are connected to Aircraft Power.

 

[Avanza]

Do you have a single antenna for NAV and GS ? No diplexer or Splitter ?
I would remove the NAV-coax at both ends between the GTN and the antenna.
Test the cable with an insulation tester at 500 V between center and GND.
Then check for continuity with an ohm meter.
Or replace one BNC/ TNC at a time and check.

Good luck

 

[Tony Kirk]

P1004 Connector

Be sure you installed the P1004 connector "upside down" with the wide part of the connector to the bottom. All the other connectors in the backplate install with the wide part up. I have seen builders install the P1004 the same direction as all the others a few times.
.

 

[Ed_Wischmeyer]

Do you have a single antenna for NAV and GS ? No diplexer or Splitter ?

IIRC, the GTN has an internal splitter, so only one antenna for NAV. Neat!

 

[pilotpat]

It's likely a long shot, but I had a similar issue. I had an RS232 signal going to the G5 and the PFD. The red X disappeared after I disconnected the G5 TX line from the circuit, which I had erroneously connected.

 

[toolmanmike]

I feel pretty dumb!

Thanks to all who chimed in here. It took me awhile, but I checked each suggestion and guess what???
I have the 1004 connector installed upside-down! I feel pretty foolish. It really is easy to do and everything else seemed to work so I saved that for last, and wouldn't you know it!
Thank God it didn't damage the radio! I am still really shocked that the unit even plugged in at all. Anyone else- please learn from my dumb mistakes! I have spent hrs tracing wires and such.

One last issue: I get the message "cross fill turned off". when I go to the setup to turn it on it is grayed out and my flight plans will not crossfill. Any suggestions?

 

[mburch]

I get the message "cross fill turned off". when I go to the setup to turn it on it is grayed out and my flight plans will not crossfill. Any suggestions?

Do you have a second Garmin IFR navigator that's not visible in the photo? If not, then this feature isn't applicable to your installation and should be disabled.

 

[toolmanmike]

So the flight plan function on the g3x main screen will not cross fill to the gtn650? I thought I could do a flight plan on either screen and have them transfer seamlessly.
I’ll admit, I’ve only begun to understand what this system can and will do.

Thanks for the input.

 

[mburch]

So the flight plan function on the g3x main screen will not cross fill to the gtn650? I thought I could do a flight plan on either screen and have them transfer seamlessly.

What you are calling "crossfill" is actually the Connext RS-232 interface (GDU 4xx to GTN) and the MapMX RS-232 interface (GTN to GDU 4xx). This is described in section 2.1.1.10 of the current installation manual (revision AU) and section 8.11 of the current G3X Touch pilot's guide (revision Y).

What Garmin calls "Crossfill" is a feature specifically to allow two IFR GPS navigators (GTN, GNS, etc) to share flight plans with one another. If you don't have two Garmin IFR GPS navigators, you don't need this.