Rob,
serial #1 on the 430W is CHNL 1 :Arnav/ei-fue output:Aviation (img_0007)
EFIS is set on serial Port #1 Function:AVTN/ARNAV. (img_0003)
1. Verify the RS-232 wiring between the EFIS and the 430W: Wiring can't be an issue because if 430W is set to icarus the EFIS receives the signal.
2. Verify that you have current software in the EFIS. Current software is S8.7.10-MV15 (Aug 20 2012) (img_0009)
3. Is the EFIS displaying fuel flow data ? How can I check this without running the engine (plane still without wings in the workshop)
By the way I did with the former icarus setting also the ARINC test without a problem but as you see in the image it says ARINC:NA?