A rain sensor also referred to as a rain switch is mainly a switching device which activates the windscreen wipers when water touches the windshield. Modern vehicles have a sensor installed that use the so-called total internal reflection principle. Infrared light is reflected at a 45-degree angle on the windshield from the inside of the vehicle. If the glass happens to be wet, less light will hit the sensor, and that will trigger the wipers. Many vehicles that use this sensor have the option to turn on the ‘Auto’ feature.
The car rain sensor, for the most part, does not easily malfunction, and it’s not easily tricked. However, the sensor can burn out at times which will require replacement. If you notice that despite water hitting your screen the wipers do not turn on, there is a chance that the sensor is not working and will need to be replaced. Fortunately, replacing the sensors is not expensive or time-consuming in most vehicles, it’s something that can be undertaken by any certified mechanic.
At car-parts.ie, we sell a selection of sensors by OEM manufacturers such as VEMO and METZGER among many others. However, to buy the right sensor you need to match the part number on the existing one with that of the ones listed above. If you still need help, do not hesitate to call or email us right away.