Hello. I have the Garmin G3X in my plane. Have the Garmin GTX23ES transponder. The GDL39 is installed for adsb “in” and I just installed the Garmin GPS20A for adsb out.
I wired it into the transponder via the two rs232 ports in the pin out instructions. I also tied it into the canbuss system. I’m receiving all the weather information through the gps waas antenna that is hooked to the gps20a.

When I run the FAA adsb report it says I failed the SIL and SDA section. Also when flying with a friend all the shows up is my plane with the altitude but no tail number. I have the tail number entered into my g3x under the transponder configuration page.

I called Garmin and spoke to two of their staff. They informed me that I should select IFR 1E-7 as the position integrity. It was set on the VFR GPS. So I set it to the new setting and I can’t get the FAA adsb report to come up nor am I showing up on ADSB using a second foreflight with stratus.

My transponder is firmware 7.04 and that is from 2015. Garmin wants me to update firmware at an authorized dealer thinking this “might” be the issue. But I just read a forum post on cubcrafters of the same equipment and issue I’m having. His solution was to switch to the IFR 1E-7. But like I said, tried it and get nothing at all when I go to that setting.

Any ideas?