Rain Sensor
WARNING: This page is about a different car, the 2023 Ford Bronco Sport. However, it is still accessible from the selected car via links, so may be relevant.
The rain sensor uses an infrared beam to optically sense water on the windshield. The intensity of the reflected beam is measured and compared to the intensity of the transmitted beam. If there is water on the surface of the windshield, the beam distorts, reducing the intensity of the beam. If the beam is not reflected completely, it is interpreted as rain on the windshield and the windshield wipers are activated.
A gel-type lens is used as the interface between the rain sensor and the windshield. The rain sensor gel-type lens is part of the rain sensor. If the lens is missing or damaged, the rain sensing wipers can be inoperative, and a new sensor must be installed.