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HELP! ARINC, Garmin GPS 175 GRT Horizon Set up

macflyer

Active Member
I'm trying to set up my 10.1 GRT Horizon, ARINC 429 and the Garmin GPS 175. I believe I have everything installed correctly, but I do not get the MAP on the Horizon to come up? It is simply black. Can someone give me the configuration setting I need for the Horizon and the Garmin GPS 175 to communicate with each other?
Thanks for you help!
 
It might help if you tell what you have done so far----wiring and config stuff.

Dont forget that the GRT serial ports have more than a single layer for each port. Baud rate is buried under the port assignment IIRC.
 
Lots of possibilities. I'd start by making sure the map data is loaded in the Horizon. If not, download it from GRT web site onto a memory stick, then transfer to the Horizon.
I think the RS232 out (on the gps) and in (on the Horizon) should both be set to format 'Aviation', and baud speed '9600'. For full functionality you'll also need the ARINC hooked up but I *think* the RS232 connection should get you the GRT moving map.
 
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Hi Bob,
I need to get out to the airport to check all the settings. The ARINC is hooked up and I am getting readings on the Horizon counter in the set up menu. The GPS 175 I believe is configured correctly. The Horizon says I have Map data loaded, but can reload again. Thanks for your help!
 
Black map means no map data. Double-check you've got the map database properly loaded - it will show up in the boot up screen and is also accessible from the set menu. No version/date information would indicate no map data loaded.

Arinc 429 data is absolutely NOT needed for the GRT map function to work. Do you have the GRT GPS puck installed? If so, configure GPS2 as that "internal" GPS and set the Horizon to use GPS2 as its position source. This should bring your map up independent of any connection to the Garmin navigator.
 
Here is my Config for the GRT Horizon. I do not have the GRT puck. I was going to depend on the Garmin to provide the GPS info.

ARINC MODULE CONNECTED: YES. Port 2
ARINC RECEIVE RATE: Low
ARINC TRANSMIT RATE: Low

Serial port 2 setup
Rate:9600
Input: GPS 1 Aviation/Map Com
Output: Fuel/Air Data

Garmin 175 Config
Format: EFIS/ADC
Format: GAMA Format 1
Speed;Low
SDI: LNAv1

Thanks for your help!!
 
I have a 420W, not a 175. And I am not at the airport. But I *think* the gps RS232 out format is set to ‘aviation’, not efis.
 
Thanks

Thanks, I will try "Aviation" on the Garmin 175. Do I need the puck from GRT? I thought the Garmin would supply the GPS info for the Map to work. The navigation base is loaded into the GRT, but the Map is black? I changed the color, but still black.
Thanks for your help!
 
If you designated the Garmin as a gps for the grt it should work. Mine uses the 420 first, and reverts to the gps in my Skyradar if the garmin is off.
 
Where do I designate the Garmin at? I thought the ARINC once hooked up and working would push the GPS signal to the GRT Horizon?
 
BTW, most will tell you, GRT has great products but lags behind in documentation. Here’s a tip: you can use the more complete, ‘legacy’ HX manuals (3 of them) for nearly everything. The internal software is pretty much the same. That’s where I found the ‘aviation’ format specified for a 430.
 
Where do I designate the Garmin at? I thought the ARINC once hooked up and working would push the GPS signal to the GRT Horizon?

No, for all functionality you need both. The basic gps info travels over the RS232 network, while gps approach data goes over the arinc network.
Get into the gps set up menu (probably need to boot up while holding some button down). (It may not be in your manual-Garmin tends to not publish this stuff, because you can screw things up). Once there, navigate to the RS232 set up pages, find the specific port (1,2, etc) that you are using to send data to the efis, and set speed/baud rate to 9600, format to ‘aviation’. Turn the unit off, then back on, to save the changes.
The same secret set up menu is also where you set the arinc out to low speed, gamma format.
 
I am not for sure, "IF" I have the RS232 going direct to the GRT EFIS. I believe the RS232 is going into the ARINC. Yes, GRT certainly lacks on some of their information when it comes to the technical side!
 
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I am not for sure, "IF" I have the RS232 going direct to the GRT EFIS. I believe the RS232 is going into the ARINC. Yes, GRT certainly lacks on some of their information when it comes to the technical side!

Okay, that won’t work. RS232 and ARINC are two different - both hardware and software - systems for sending data from one box to another. They are not at all interchangeable. I’d suggest you download and read thru the grt HX manuals (installation, set-up, user) before going too much further.
Typically each box will have several RS232 ‘ports’. Each port will have one ‘in’, one ‘out’. Each in and out can be assigned its own ‘format’, but typically there is only one speed (or baud rate) for both. So figuring out which port will be used for what takes some thought and layout. It’s not hard to run short of ports. The format of an ‘in’ must match the format of the ‘out’ that it’s hooked to, although sometimes different format names are compatible (no one said this is easy). Best to follow the recommendations in the manuals. RS232 uses the aircraft ground as a signal return line.
ARINC is electrically different. It has two wires (A and B, always connect A to A, B to B, when connecting two different boxes).
With both RS232 and ARINC, one ‘out’ can drive several ‘ins’; but each ‘in’ can only be hooked to one ‘out’.
 
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Thanks everyone! I will get to the airport tomorrow and check recheck everything! Cheers and Happy New Year!
 
I just went through this with my GPS 175, GRT ARINC and Sport EX. This is what GRT sent me to get it working correctly.

GPS175 Settings:

ARINC RX Port 1:
Format: EFIS/ADC
Speed: Low

ARINC TX Port 1:
Format: GAMA Format 1
Speed: Low

RS232 Port 1: Aviation Output 1

The 175 does not have an RS-232 Fuel/Air Data (FADC) input like other Garmin IFR GPS units.

EFIS Settings in SET MENU, General Setup:

For units with external ARINC module: ARINC Module Connected: Yes, Port (select port it's wired to)

ARINC Receive Rate: Low
ARINC Transmit Rate: Low

Serial Port 3 Rate: 9600
Serial Port 3 Input: GPS1 Aviation/MapCom
The Serial Port Output is not used for the 175 and can be used for unrelated functions at 9600 baud.
Using GPS1 for the GPS175 is recommended and sometimes required. Change any other GPS to GPS2.

If the ARINC module is connected to port 6, the settings would look like this:
ARINC Module Connected: Yes, Port 6

Other settings in General Setup:

ARINC GPS Input: GPS1
This tells the EFIS to use the GPS data from the ARINC-429 connection when GPS1 is selected.

NAV Mode Source: Internal
The GPS175 does not have a built-in VOR/ILS receiver, so all mode changes must be done in the EFIS.

GPS1 Flight Plan Source: External
This tells the EFIS to use GPS flight plan data from the GPS175 RS-232 connection.

GPS2 Flight Plan Source: update this to match your GPS2, if any.
GRT GPS units should be Internal. GPS units that transfer flight plan data should be External.

Virtual GPS2: Normally Off unless you know you want this feature.
If you have two GPS inputs this must be Off.

Settings in SET MENU, Primary Flight Display:

To enable the approach modes and PFD indicators, you must configure the ILS display:

ILS Type: pick Needles or Scales as preferred
When some other features are turned on, only Scales mode is possible.

Show VOR CDI on Localizer: No, unless you have a VOR input.

Show GPS CDI on Loc/GS: Yes
This displays the GPS approach deviations on the ILS indicators.
This is required for the GPS approach display and capture modes in the EFIS.

Hopefully this helps.
 
Thanks for all your help!

Thanks for all the help! I did not have an RS232 from the Garmin 175 ran to a serial input in the GRT Horizon EFIS. Once I ran the from the 175 to the serial port on the EFIS, I powered everything up and had GPS signal and Map!

Have a great New Year! Blue skies!
 
Good for you, thanks for reporting back with the solution to the issue----might help someone else in the future.
 
New install

I am in the process of wiring a new Garmin 175 to a Horizon 10.1 . By now I am sure many have done so. What wires on the Garmin go to what pins on the Horizon. Im using a GRT autopilot and arnic. Any help what be great.
 
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