There are some LED status code and it depends in the Erle-Brain 3 autopilot status. There are 3 normal status:
Autopilot is not launched yet or cannot be launched. If the autopilot is not launched the three LED will be switched on. Also can happen that the autopilot is not launched because an error.
The Autopilot is launched but it is not armed. If the autopilot is launched and not armed the green LED will be ON and the orange will be blinking. Take into account that not all vehicles have the
disarmed status, like Erle-Rover or Erle-Plane.
The Autopilot is launched and it is armed. If the autopilot is launched and armed the green and orange LED will be ON.