For LOS (Loss of Signal) red lights on fiber or advanced gateways, it usually means the incoming optical line is not detected or has low signal. Double-check that the fiber line is connected properly and that there's no bend or physical damage. When it's green and steady, everything is fine. However, when it blinks red or stays solid red, it signifies a Loss of Signal, a problem preventing your router from communicating. A red light on your router can be a source of frustration and confusion. In this comprehensive guide, we will walk you. What Does a Blinking Red or Orange Light on a Router Mean? A blinking red or orange light typically signals an issue with your internet connection or router configuration.