GPS mode not working ( again)

[bpieke]

I had a previous post regarding the just flight Arrow where I couldn't get the autopilot to follow the gps.
I have also tried this in the C414 and the same problem. It works with heading mode in the settings, but not with nav mode.
When I select the gps mode in goes into standby mode ( lower box ) in the autopilot and rol mode remains active. When I change to heading mode in the settings, the heading mode goes into the active ( top box ) on the autopilot and the gps remains in the standby, and it will track the gps path .

I downloaded the PMS GTN to try it and it works as normal. e.g. the GPS shows in the active box and it tracks the gps, so it is only an issue with the TDS GTN. I seem to be the only one having this problem.

As was mentioned above, what you are seeing may indeed be normal (correct) behavior.
NAV mode does not activate unless you are close to the magenta line. The PMS unit uses a simplified (incorrect) process.

With NAV mode active, but not captured, use HDG mode to intercept the magenta line. You will see GPS moving from the bottom to the top at NAV capture.  This is the way the real unit works.  (The WT G1000 NXi displays similar behavior).