A purple light on your Verizon Fios router can indicate a number of things. A red light engraved on the stone means that a hardware / system failure has been detected. A fast blinking red light means your router is overheating. And finally, the red light technology slowly blinks with WPS pairing error.
The world of status indicators
Blue when lit indicates successful pairing, combined with indicates pairing mode if also blinking slowly. Green means Wi-Fi is disabled. Solid yellow means no internet connection. Red can also indicate hardware or system degradation (solid), overheating (blinking fast), or pairing failure (slow blinking).