To be sure are you going through the startup checklist when starting cold and dark at the ramp to ensure you have all avionics set right? Early on when I was being stupid I once couldn’t figure out why the TBM auto pilot would not turn on with my Saitek Multi panel even though I kept on pressing the button on the Garmin.
Figured out because the AP witch up top on the ceiling panels wasn’t on so the aircraft true world settings do affect the panels accordingly.