A circuit is disclosed for detecting and eliminating the buildup of snow and/or ice on the viewable face of an LED traffic signal lens. The circuit measures the ambient temperature within the LED signal, and when the temperature falls to a level where snow and/or ice accumulation can occur, the circuit begins looking for snow and/or ice buildup on the lens of the LED signal. An infrared LED transmits a signal which is reflected when snow or ice is present on the lens of the traffic signal. When the reflected signal is received by an infrared receiver, it sends a signal to a microcontroller, which analyzes the signal to determine if it is a valid signal. If it is, a heater is turned on until the ice and snow are removed.

 
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