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Garmin G5 as Secondary Flight Display in G3X System

Jeff A

Jeff A

Well Known Member
So, I currently have a dual screen G3X Touch system with a GTN-650. Been flying flawlessly for almost two months. I decided to add a G5 as a secondary flight display. "Finished" the install today, but haven't had a chance to fly with it yet.

I wired:

1 - CAN-H
2 - CAN-L
3 - (empty)
4 - RS-232 RX 1 (RS-232 Out 3 on GTN-650)
5 - (empty)
6 - RS-232 Ground (RS-232 Gnd 3 on GTN-650)
7 - Power
8 - (empty)
9 - Power Ground

I configured the G5 as "G3X System Backup" and performed the Pitch/Roll Calibration. I did not connect a GPS antenna to the unit. Connected Pitot and Static lines to the unit and installed the backup battery. Can't tell from the installation manual that there is much else to accomplish since it's part of the G3X system.

So, here are a few questions:

Did I need to wire the RS-232 if the G5 is configured as "G3X System Backup"? I'm unable to select MAPMX (or MAPMX Format 2) on the GTN RS-232 # 3 Output...presumably since I already chose MAPMX for the output to the PFD. I currently have selected Aviation Output on the GTN and Aviation Input on the G5.

Should the Flight Director show up on the G5?

Why do I have a red 'AFCS' indication?



All of the Device Information looks good and seems to be communicating properly (everything has a green checkmark next to it).

It would seem as though I'm missing a simple step or two in the installation process... As always, any help and advice is appreciated.
 
Last edited:
Jeff A said:
So, I currently have a dual screen G3X Touch system with a GTN-650. Been flying flawlessly for almost two months. I decided to add a G5 as a secondary flight display. "Finished" the install today, but haven't had a chance to fly with it yet.

I wired:

1 - CAN-H
2 - CAN-L
3 - (empty)
4 - RS-232 RX 1 (RS-232 Out 3 on GTN-650)
5 - (empty)
6 - RS-232 Ground (RS-232 Gnd 3 on GTN-650)
7 - Power
8 - (empty)
9 - Power Ground

I configured the G5 as "G3X System Backup" and performed the Pitch/Roll Calibration. I did not connect a GPS antenna to the unit. Connected Pitot and Static lines to the unit and installed the backup battery. Can't tell from the installation manual that there is much else to accomplish since it's part of the G3X system.

So, here are a few questions:

Did I need to wire the RS-232 if the G5 is configured as "G3X System Backup"? I'm unable to select MAPMX (or MAPMX Format 2) on the GTN RS-232 # 3 Output...presumably since I already chose MAPMX for the output to the PFD. I currently have selected Aviation Output on the GTN and Aviation Input on the G5.

Should the Flight Director show up on the G5?

Why do I have a red 'AFCS' indication?



All of the Device Information looks good and seems to be communicating properly (everything has a green checkmark next to it).

It would seem as though I'm missing a simple step or two in the installation process... As always, any help and advice is appreciated.
Click to expand...
Go into the G3X configuration and see if you see the G5 with a green check mark. You need to give the existing MAPMX line going to the G3X a parallel line to the G5 as well.
 
This is one place where garmin falls short. They have great schematics for the g3x and for the g5 in their respective manuals but once you want to combine them with their products, watch out.

It would be cool if garmin had an app where you enter in your devices and it shows you the complete system schematic. For example I want to do a whole g3x with a g5 backup, a Gns530w, a gtx345, and a gma245 audio panel. The gtx 345 manual has to be requested from garmin as they don’t just put that one out on their site....then you have to infer that somewhere there has to be an rs232 connection that isn’t listed in any of the manuals in order for the 345 to pass wx info.

Same sort of thing in this case. One would assume you need a separate line to the 650, not a parallel line with the g3x.
 
Jesse said:
Go into the G3X configuration and see if you see the G5 with a green check mark. You need to give the existing MAPMX line going to the G3X a parallel line to the G5 as well.
Click to expand...

Yes, the G5 has a green check mark on the G3X Configuration page...it's communicating well on the CAN bus.



So, the MAPMX [Format 2] output line from the GTN to the G3X PFD should be spliced and also sent to the G5 RS-232 Input?

Maybe I've been mis-undestanding RS-232 all these years...I always thought they had to have dedicated receivers and transmitters and couldn't be shared/paralleled.
 
Last edited:
Jeff A said:
Yes, the G5 has a green check mark on the G3X Configuration page...it's communicating well on the CAN bus.



So, the MAPMX [Format 2] output line from the GTN to the G3X PFD should be spliced and also sent to the G5 RS-232 Input?

Maybe I've been mis-undestanding RS-232 all these years...I always thought they had to have dedicated receivers and transmitters and couldn't be shared/paralleled.
Click to expand...

Hello Jeff,

We don't recommend you run G5 V5.00 software in the EAB installations yet. We are working on a G3X Touch V5.70 release that adds support for that. You will notice that there is an asterisk next to the V5.00 software line in your screenshot which indicates the G5 is not using the same software delivered with G3X Touch V5.60.

The EAB G5 software download page has V4.10. The G5 V5.00 software download is on the certified G5 software download page.

And yes, you should run the MapMX Format 2 transmit line from the GTN to both the PFD and the G5. We normally do this from the PFD. It is optional that you wire the MapMX data line to the G5, but if you don't do this, you can't turn off your big display and still fly a coupled LPV approach with the G5 based autopilot.

Thanks,
Steve
 
Last edited:
g3xpert said:
Hello Jeff,

We don't recommend you run G5 V5.00 software in the EAB installations yet. We are working on a G3X Touch V5.70 release that adds support for that. You will notice that there is an asterisk next to the V5.00 software line in your screenshot which indicates the G5 is not using the same software delivered with G3X Touch V5.60.

The EAB G5 software download page has V4.10. The G5 V5.00 software download is on the certified G5 software download page.

And yes, you should run the MapMX Format 2 transmit line from the GTN to both the PFD and the G5. We normally do this from the PFD.

Thanks,
Steve
Click to expand...

Perfect. Thank you. I'll load the other software (was just using what it shipped with) and fix my MAPMX lines.
 
Jeff,

I should have mentioned that you can select (highlight) the G5 System Software on the right page of your screenshot, press Menu, then downgrade the G5 software from V5.00 to V4.10. Your PFD is already holding the correct software for the G5.

No need to download the G5 V4.10 software from the web page and upgrade it with a micro SD card.

Thanks,
Steve
 
Jeff A said:
Maybe I've been mis-undestanding RS-232 all these years...I always thought they had to have dedicated receivers and transmitters and couldn't be shared/paralleled.
Click to expand...

It?s just like talking. One ear can only listen to one voice at a time, but one voice can be heard by many ears at the same time. One output can talk to many inputs, but one input can only accept one output.
 
G5 Software Version

g3xpert said:
Jeff,

I should have mentioned that you can select (highlight) the G5 System Software on the right page of your screenshot, press Menu, then downgrade the G5 software from V5.00 to V4.10. Your PFD is already holding the correct software for the G5.

No need to download the G5 V4.10 software from the web page and upgrade it with a micro SD card.

Thanks,
Steve
Click to expand...

Just wanted to clarify, V4.10 was not in the G3X already. It downgraded to V4.00. Not sure what the difference is between 4.00 & 4.10. I went ahead and downloaded 4.10 and installed on the G5 without any issue.

One question still remains....does the G5 NOT display the Flight Director when it's setup as a G3X Backup Display? Mine is not displaying the FD or any AFCS modes.
 
Jeff A said:
Just wanted to clarify, V4.10 was not in the G3X already. It downgraded to V4.00. Not sure what the difference is between 4.00 & 4.10. I went ahead and downloaded 4.10 and installed on the G5 without any issue.

One question still remains....does the G5 NOT display the Flight Director when it's setup as a G3X Backup Display? Mine is not displaying the FD or any AFCS modes.
Click to expand...

Hello Jeff,

Yes, this is correct that V5.60 G3X Touch software contains G5 V4.00. Either G5 V4.00 or V4.10 should be fine with GDU V5.60.

The pre-V5.00 versions of G5 software do not show the flight director or flight director modes on the G5 when the big display(s) are operational and the G5 is not providing the backup autopilot function, but the next G3X Touch software update should include a version of G5 software that does.

Thanks,
Steve
 
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