How do you test a rain sensor on a car?

Use a spray bottle to wet the outside surface of the front windshield until you see water heavy beads. Turn the ignition key to the “On” position. Turn the rain sensor switch to the “On” position. If the wipers do not move, refer to your owner’s repair manual for the location of the rain sensor module.Click to see full answer. Just so, how do I know if my car has a rain sensor?First, if your wipers automatically turn on when raindrops come in contact with the windshield then you have a sensor. You can also check by looking from the outside – behind the rear view mirror. If you see a strip of lens or film that faces the outside that is adjoining your light sensor.Subsequently, question is, what do rain sensors look like? The rain sensor looks like a small metallic black sticker on the windshield, and the control box is a plain black box on the inside of the vehicle that control the sensors commands. Herein, how does a rain sensor work on car? The rain sensor works on the principle of total internal reflection. An infrared light beams at a 45-degree angle on a clear area of the windshield from the sensor inside the car. When it rains, the wet glass causes the light to scatter and lesser amount of light gets reflected back to the sensor.How do you fix a rain sensor wiper? How to Troubleshoot Rain Sensing Wipers Place the vehicle in park or neutral with the emergency brake set. Clean the outside of the front window with window cleaner and towels. Use a magnifying glass to inspect the entire outside surface of the windshield. Look at the small box-like sensor on the inside of the windshield in front of the rear view mirror.