pecanflyboy
Well Known Member
G3X, GDU370, GDU375, GTN650xi, with a GSU73. Upgrading to two GDU470 portrait displays. Things to know:
1. If you are going to use an Apple iPad to send flight plans from Garmin Pilot to a GTN, you must change the green configuration module in the PFD1 connector to a black configuration module. Must purchase separately.
2. There is no interconnect diagram to wire Connext when using the GSU73. Use the GAD29 Connext to any open RS232.
Referencing Rev AP of the G3X installation manual, and Rev 5 of the GTN650xi manual, the GSU73/GTN interconnect is on page 28-11. However, Garmin has directed me to the GAD29/GTN interconnect on page 27-40. This shows and RS232 connection between the GTN and the GDU4X0 using the GAD29 (3 wires). Garmin has confirmed that I can use this interconnect and associated Configuration Guidance for the GAD29 with the GSU73.
2.1 The interconnect diagram for the GSU73 between the GTN and the GDU37X for the MAPMX data only shows an RS232 "out" from the GTN to the GDU37X. You will get red "X's" in the NAV1 tuning on the GTN470 in this configuration. The fix is to add a RS232 "in" to the GTN from the GDU470 on the same channel. The GDU470 adds the function of tuning GTN frequencies remotely. For this to work, the GTN needs to receive data from the GDU (this was not a function of the GDU37X). Basically, the MAPMX needs data flow to and from to function properly.
3. For some reason Garmin made the mounting hole dimensions for the GDU470 just slightly wider than the GDU37X. So, you have to alter the panel and use a new mounting plate which must be purchased separately in an installation package. The holes are only a half a diameter apart (I suspect the engineers used the hole outer dimension of the GDU37X as the center dimension of the GDU470). If moving nutplates, you will not have edge distance unless you rotate the nutplate which is hard to do with the limited space. The installation kit nutplate is 1/4" wide and will work if you have the space. I had a supporting angle between the GDU's and was unable to use individual nutplates. So, I rebuilt the panel and powder coated. See pics
https://drive.google.com/drive/folders/1SUvk8HOEVLJBjHkp10NvQqzYyJfhXkkv?usp=sharing
4. The GDU470 is 1.5" + deeper than the GDU37X and the plugs are in a different position. If other components are closely mounted behind the GDU37X, you will have to move them and take into account that the plugs are more centered on the GDU470 and the installation is deeper.
5. If you are IFR, you will need to get another IFR pitot-static check to be in compliance since this is a new altimeter and/or you may have disconnected the pitot-static lines during installation.
6. You must re-configure ALL settings on the GDU470 after you erase or replace the configuration module. NOTHING transfers. This means you need to take pictures of all your configuration settings and menu settings before. Also, you will need to copy and save the fuel level calibration to the SD card as you will use this file to transfer these settings to the GDU470.
I'll update as I get information from Garmin, and lessons I learn during the installation.
$$
1. If you are going to use an Apple iPad to send flight plans from Garmin Pilot to a GTN, you must change the green configuration module in the PFD1 connector to a black configuration module. Must purchase separately.
2. There is no interconnect diagram to wire Connext when using the GSU73. Use the GAD29 Connext to any open RS232.
Referencing Rev AP of the G3X installation manual, and Rev 5 of the GTN650xi manual, the GSU73/GTN interconnect is on page 28-11. However, Garmin has directed me to the GAD29/GTN interconnect on page 27-40. This shows and RS232 connection between the GTN and the GDU4X0 using the GAD29 (3 wires). Garmin has confirmed that I can use this interconnect and associated Configuration Guidance for the GAD29 with the GSU73.
2.1 The interconnect diagram for the GSU73 between the GTN and the GDU37X for the MAPMX data only shows an RS232 "out" from the GTN to the GDU37X. You will get red "X's" in the NAV1 tuning on the GTN470 in this configuration. The fix is to add a RS232 "in" to the GTN from the GDU470 on the same channel. The GDU470 adds the function of tuning GTN frequencies remotely. For this to work, the GTN needs to receive data from the GDU (this was not a function of the GDU37X). Basically, the MAPMX needs data flow to and from to function properly.
3. For some reason Garmin made the mounting hole dimensions for the GDU470 just slightly wider than the GDU37X. So, you have to alter the panel and use a new mounting plate which must be purchased separately in an installation package. The holes are only a half a diameter apart (I suspect the engineers used the hole outer dimension of the GDU37X as the center dimension of the GDU470). If moving nutplates, you will not have edge distance unless you rotate the nutplate which is hard to do with the limited space. The installation kit nutplate is 1/4" wide and will work if you have the space. I had a supporting angle between the GDU's and was unable to use individual nutplates. So, I rebuilt the panel and powder coated. See pics
https://drive.google.com/drive/folders/1SUvk8HOEVLJBjHkp10NvQqzYyJfhXkkv?usp=sharing
4. The GDU470 is 1.5" + deeper than the GDU37X and the plugs are in a different position. If other components are closely mounted behind the GDU37X, you will have to move them and take into account that the plugs are more centered on the GDU470 and the installation is deeper.
5. If you are IFR, you will need to get another IFR pitot-static check to be in compliance since this is a new altimeter and/or you may have disconnected the pitot-static lines during installation.
6. You must re-configure ALL settings on the GDU470 after you erase or replace the configuration module. NOTHING transfers. This means you need to take pictures of all your configuration settings and menu settings before. Also, you will need to copy and save the fuel level calibration to the SD card as you will use this file to transfer these settings to the GDU470.
I'll update as I get information from Garmin, and lessons I learn during the installation.
$$
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