Q: How Does a Rain-Sensing Wiper System Work?

asked by on November 23, 2015

How does a rain-sensing wiper system work?

Rain-sensing wipers operate based on an infrared light mounted by the rear-view mirror. A light beam is reflected off the windshield at a 45-degree angle. If there is rain, snow, or something else on the windshield, less light reflects back to the sensor and the rain-sensing wipers turn on. The wiper system is still equipped with an override to control high and low speeds in the case of rain-sensing wiper malfunction.

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