How Do Rain Sensor Wipers Work and Are They the Right Choice for You?

Everybody knows driving during a thunderstorm is a bad idea, but there’s no helping it if it suddenly starts pouring while you’re out and about. You’ll want to drive as safely as possible, with your headlights and windshield wipers on.

Unfortunately, constantly switching your windshield wipers’ speed can be distracting, especially when you’re driving on a busy road. While you can’t control the weather, you can certainly control the features in your vehicle that can make driving in bad weather easier, like installing rain sensor wipers.

What Are Rain-Sensing Wipers?

Unlike traditional windshield wipers, rain-sensing wipers automatically start working once raindrops start falling on your windshield. These auto wipers can also adjust their speed depending on how intense the rain is, making them incredibly convenient for drivers who don’t want anything distracting them from driving.

How Do Automatic Windshield Wipers Work?

Here’s the short answer: rain-sensing wipers automatically turn on thanks to rain sensors located in between the windshield and rear view mirror. As for the long answer, this is where things get a little more complicated.

Each rain sensor contains a light source called a light-emitting diode (LED) and a light detector. When this light detector doesn’t receive enough light from the LED, it sends a signal that activates the windshield wipers.

With a dry windshield, the light from the LED reflects off the surface of the windshield and into the detector uninterrupted. When it rains, raindrops on the windshield cause the light to scatter, which means the detector receives less light than usual because raindrops deflect light when they hit the glass.

This alerts the detector to rainy weather and prompts it to activate the wipers. As the detector receives less and less light due to strong rainfall, it also adjusts the wiper speed accordingly.

Advantages of Rain-Sensing Wipers

Still unsure about replacing your traditional wipers with auto wipers? Here are a few things that might help you make up your mind:

Convenient Safety Feature

Rain-sensing wipers might seem like an unnecessary feature, especially since turning on traditional wipers isn’t really difficult. Still, rain-sensing wipers are incredibly convenient if you live in an area with extreme weather conditions.

Adjustable Sensitivity

Rain-sensing wipers do a lot of the work for you. They turn on automatically and adjust their speed on their own, but this doesn’t mean you can’t control them anymore. Most auto wipers come with controls that let you adjust their level of sensitivity.

On low sensitivity, only a large amount of water on your windshield will activate the auto wipers, while on high sensitivity, the wipers will turn on when their rain sensors detect small drops of water on your windshield. Thanks to this feature, you can adjust your auto wipers’ sensitivity according to your own preference.

Different Sizes

Yet another great thing about auto wipers is that they come in different sizes, which means you’re likely to find the perfect fit for your specific vehicle. However, this also means you’ll have to be careful about buying rain-sensing wipers, as not every kit is going to fit your vehicle.

Disadvantages of Rain-Sensing Wipers

Of course, rain-sensing wipers aren’t perfect. No matter how convenient they might be, they still come with their fair share of disadvantages.

Sensitive to Dirt and Other Debris

Unfortunately, rain-sensing wipers don’t just detect rain. They’re sensitive to pretty much anything that falls on your windshield, so they can suddenly turn on if snow, leaves, or insects fall on your windshield.

Dirt can also set off your auto wipers, so you might have to switch your wipers off manually or turn down their sensitivity if you haven’t been able to clean your windshield yet.

Can Malfunction

Auto wipers rely on their rain sensors to turn on, so a faulty rain sensor will most likely prevent your wipers from working automatically. Because rain sensors work by detecting light on your windshield, even the tiniest crack can interfere with your rain sensor and prevent it from activating your wipers.

Any dirt or grime on your windshield can also block your rain sensor, forcing your auto wipers to stay off.

Can Stop Working After a Windshield Replacement

A rain sensor is usually designed to work with a specific windshield, so if you replace your windshield, your auto wipers might not work. Because of this, most manufacturers recommend also replacing your rain sensors if you have to replace your windshield.

In some cases, recalibrating your rain sensors should be enough to get them working again, assuming your new windshield is compatible with your rain sensors.

Do All Vehicles Have Rain-Sensing Windshield Wipers?

No, not all vehicles have rain-sensing wipers, but a good majority of modern vehicles do. In fact, automatic windshield wipers have become a standard for many modern vehicles, even if they weren’t always popular among auto manufacturers.

Originally, most vehicles came with manually operated windshield wipers, which drivers could only activate by constantly turning a lever in the cabin. By the time electric motor cars entered the market, most vehicles came with a simple switch that could turn the wipers on and adjust their speed.

In 1956, the Chevrolet Bel Air introduced an optional feature for their windshield wipers: a rain sensor mounted on the windshield. By the 1990s, rain sensors became widely available on the market and these soon became a standard feature for new vehicles.

Get Replacement Rain Sensor Modules and Refurbish Kits

Rain sensor wipers take their cues from the rain sensor module, which evaluates the sensor readings and determines when to activate and deactivate the windshield wipers. If something goes wrong with the module, it might cause problems that affect other parts. For replacement rain sensor modules that you can depend on, order from CarParts.com.

At CarParts.com, finding a new rain sensor module that fits your vehicle is simple and straightforward. Just plug your car’s year, make, and model into our vehicle selector and browse the list of products for the one that fits your needs. We source our parts from trusted brands, ensuring that your new windshield parts and accessories will deliver the performance they promised. After completing our easy ordering process, you won’t have to wait long for your replacement part. If you live in the continental US and submit your order before noon ET, you can expect to receive your new rain sensor module in as fast as two business days.

Get the best bang for your buck with competitively priced, high-quality replacement rain sensor modules at CarParts.com. Check out our selection of rain sensor modules and enjoy big discounts today!