I use my GTN 750 with my A2A C172 and it works great. However when I load my A2A Piper Cub the GTN 750 panel opens but will not turn on. I have heard the Flight1 GTN 750 may need to see at least 10 volts from the aircraft to operate but I don't think there are any battery supplied instruments in the Piper Cub and this could be the issue. Has anyone been able to turn on one of the GTN navigation devices in an A2A Piper Cub? Is there a modification that could be made to the panel config file to fool the GTN 750 at start up?