Wire connections
I have a 296 (predecessor to 496) and am preparing for an Aera 660.
The wiring connection points are:
D180 EFIS D-25:
Pin 22 (yellow wire in Dynon harness) Serial 1 RX
Pin 9 (black wire in Dynon harness) Serial 1 GND
Aera 660 Bare Wire Connector:
Blue wire: Serial 1 TX
Black wire: Power GND and data GND
Red wire: Power
Connect the yellow wire to the blue wire
Connect the black wires to aircraft GND bus
Connect the red wire to 12V
The above can be verified in the D180 Installation Manual and the Aera 660 Pilots Guide, both are available for download on manufacturer websites.