The LED’s on the PCB, the RX and the FC all communicate through the color and blinking pattern of their lights. If you’re having issues connecting to the radio controller, check out the RX section. If you suspect your flight controller is damaged, visit the FC section. Unable to arm or lift off? The LED’s bordering the PCB communicate information about GPS connectivity, arm state, battery level and more. Wondering why Rubi won’t stop beeping? Check out the Beeps section to help diagnose the problem.