Systems and methods of detecting and validating a turn light indicator in a vehicle include receiving optical perception data from an optical perception system. The optical perception data includes data describing a detected turn indicator light of another vehicle perceived by the optical perception system including a status of the detected turn indicator light. A turn indicator light signal is generated in the form of a time varying waveform based on the status of the detected turn indicator light. A duty cycle and frequency of the turn indicator light signal is obtained. An assessment is made whether the detected turn indicator light is a valid detection by comparing the duty cycle and frequency with predetermined bounds. When the detected turn indicator light is assessed to be a valid detection, then an automated feature of the vehicle is controlled based on the data describing the detected turn indicator light.