[May 18, 2016]

I downloaded the GTN650 maintenance manual today to see what it had to say about the causes of PTT and the NAV not working. The PTT diagnostics indicated to check the power and ground to the P1003 connector, and also check the pins are installed correctly. The diagnostics for the NAV issues were much more grim - basically telling me to send the unit back to Garmin.

When I got to the hangar tonight I quickly saw the issue - the PTT pin was bent to a point where it wasn't being inserted into the receiving connector. This probably also prevented the NAV connector from being fully seated.

I decided that using the tray was probably a good idea to prevent any more damage. With the pin replace, everything seemed to be working much better.

The NAV is no longer disabled!

I can transmit on the COM!

The GTN650 has some great diagnostics - I could see the airdata serial input on the RS232 IN 1 connector.

Also ARINC data was being received.

I spent the next few hours getting the panel back into the airplane. Everything seems to be working perfectly.

I love the way the GTN650 looks. I am very happy I upgraded. The whole installation wasn't all that bad - the worst part was uninstalling the reinstalling the panel. Everything else was rather trivial. I estimate it took about 18 hours of work for the whole process. Hopefully I can sneak in a flight test this week.



Last Modified: August 13, 2023