EFIS Installation - Garmin 496 connection

[rturn]

I recently bought an airplane equipped with a Garmin GTX330, Garmin 496, Dynon HS34, Dynon D100 EFIS and Trutrak autopilot. The RS-232 output from the GTX 330 and the serial output from the Dynon HS34 are both connected to the data-in wire for the Garmin 496. With this configuration I get aural traffic warnings (TIS) from the GTX 330 but the traffic display does not show up on the 496. The serial connection between the 496 and the Dynon equipment seems to work OK. I get wind data on the EFIS and the autopilot operates in the heading hold and GPS mode. I had an avionics tech look at the wiring and he said the serial data out wire from the Dynon HS34 was not required so he cut it. I now get the TIS display on the 496 but the data out connection from the Dynon must be required as I have lost some functions. No wind data is displayed on the D100 EFIS and the autopilot will not operate in either the heading hold or GPS mode.
It appears that the two input streams from the GTX 330 and the Dynon HS34 cannot be just spliced into the 496 data-in wire. Is there some way to get the two sets of data to the 496 with only the one data-in wire?

 

[Dynon]

Your avionics tech is right, but, it sounds like he cut the 496 out to HS34 in (and possibly to the the TT AP) connection, which is may be why your D100 isn't getting GPS for winds anymore.

I think this is what you want, from end to end:

GTX330 TIS output going DIRECTLY to the 496 serial input so that it can get traffic.
The 496 serial transmit output going to BOTH the HS34 serial input AND the TruTrak AP. The TT gets its GPS info from the 496, as does our products.
As your tech said, you don't need the serial transmit going from the HS34 to the 496. Although it's depicted in the installation diagrams, not connecting it won't affect the D100's or the 496's behavior.