Everything You Need to Know About Automatic High Beam Headlights
Driving at night can be a stressful experience, especially on dark roads with little street lighting. Constantly flicking your high beams on and off to avoid blinding oncoming traffic is not only annoying, but it can also be dangerous if you forget to switch them back to low beams. Fortunately, many modern vehicles now come equipped with automatic high beam headlights that take the hassle out of nighttime driving.
In this comprehensive guide, we’ll dive deep into everything you need to know about automatic high beams – how they work, their benefits, what vehicles have them, and more. As an automotive lighting engineer with over a decade of experience designing headlight systems for major automakers, I‘ll share my expertise and insider knowledge to help you understand this innovative technology.
What are Automatic High Beam Headlights?
Automatic high beam headlights, also known as auto high beams or intelligent high beams, are an advanced driver assistance feature that automatically switches between high and low beam headlights based on lighting conditions and surrounding traffic.
High beam headlights provide significantly more light output and throw than low beams, illuminating much more of the road ahead. This improves visibility and reaction time when driving at night, especially on roads with no streetlights. However, high beams must be switched off when there is oncoming traffic to avoid blinding other drivers.
With traditional manual high beams, the driver has to remember to switch between high and low beams. It’s easy to forget to turn off your high beams, which is not only inconsiderate to other drivers but can also result in a ticket in some areas.
Automatic high beams take the burden off the driver by using sensors to detect oncoming headlights or preceding taillights and automatically switching to low beams. Once the other vehicle has passed, the system switches the high beams back on. This allows the driver to keep their high beams on more often while minimizing glare for other motorists.
The goal of automatic high beams is to optimize visibility for the driver without negatively impacting other drivers on the road. By automating the high beam function, these systems aim to improve both convenience and safety when driving at night.
How Do Automatic High Beams Work?
Automatic high beam systems rely on advanced sensors and software to detect other vehicles on the road and control the headlights accordingly. While the exact implementation varies between automakers, most systems use the following components:
Forward-Facing Camera
The key enabler for automatic high beams is a high-resolution camera, typically mounted on the windshield behind the rearview mirror. This camera captures a wide-angle view of the road ahead and feeds that data to an image processing module.
Some of the latest systems use stereoscopic cameras with two lenses to capture 3D imagery. This allows for more precise distance measurement and object recognition compared to single-lens cameras.
Image Processing Software
Sophisticated machine vision software analyzes the video feed from the camera in real-time, looking for light sources that indicate other vehicles. Headlights and taillights have distinct shapes, brightness levels, and positions that the software is trained to recognize using computer vision and machine learning algorithms.
The software can distinguish between vehicular light sources and other lights like street lamps, reflective signs, etc. It also uses the size and position of detected lights to estimate the distance to the vehicle ahead.
Most auto high beam systems look for:
- Oncoming headlights up to 2000-3000 feet away
- Preceding taillights up to 500-600 feet away
If either of these is detected within those distance thresholds, the system will switch to low beams. Some newer systems can even selectively dim or mask a portion of the high beams to avoid glare for oncoming drivers while still providing some high beam illumination.
Headlight Controls
Once the image processing is complete, the automatic high beam module sends control signals to the headlights to switch between high and low beams. This is typically done via a relay that powers the high beam filament or shutter.
The response time from detection to switching is very fast, usually within a fraction of a second. This ensures the high beams are dimmed before the oncoming vehicle is close enough to be affected by the glare.
Some auto high beam systems also have a manual override that allows the driver to switch to low beams if needed, such as when driving in fog or heavy rain where high beams can reflect off the moisture and impair visibility.
By seamlessly detecting other road users and automatically controlling the high beams, these systems allow drivers to benefit from improved illumination without worrying about forgetting to switch their lights. Studies have shown that drivers with automatic high beams use their high beams substantially more often than those with manual control, meaning greater visibility.
The Benefits of Automatic High Beam Headlights
Automatic high beams offer several compelling benefits over traditional manual high beam control:
Improved Visibility and Reaction Time
The number one reason to use high beam headlights is the drastic improvement in seeing distance compared to low beams. High beams typically have 2-3 times the light intensity and illuminate the road up to 500 feet ahead, while low beams reach only about 250 feet.
This extra visibility is crucial when driving at higher speeds at night, as it gives you more time to spot and react to potential hazards like pedestrians, animals, or debris in the road. Even a split second can make the difference between an accident and a close call.
With automatic high beams, you get the visibility benefits of high beams without having to constantly remember to turn them on and off. The system keeps your high beams engaged more of the time, maximizing your forward lighting.
Reduced Driver Fatigue
Constantly monitoring your mirrors for other vehicles and flicking the high beam stalk gets tiresome, especially on long nighttime journeys. It’s yet another thing to keep track of on top of your speed, lane position, navigation, etc.
By automating the high beam function, auto high beam systems reduce the mental overhead on the driver. This can help with concentration and alertness, making driving at night less stressful and fatiguing.
Minimized Glare for Other Drivers
We’ve all experienced the sudden blindness of being blasted by an oncoming car’s high beams. It’s unpleasant at best and downright dangerous at highway speeds.
Unfortunately, many drivers simply forget they have their high beams on until they get flashed by another vehicle. Others don’t use their high beams at all to avoid forgetting to turn them off.
Automatic high beams help solve this issue by proactively dipping to low beams when another vehicle is approaching. This minimizes glare for other road users without sacrificing high beam visibility when the road is clear.
Some of the newest auto high beam systems can even dynamically “shadow” oncoming vehicles, selectively dimming the portion of the beam that would hit the oncoming driver while maintaining high beam intensity on the rest of the road. This allows for optimal illumination without blinding others.
Legality and Proper High Beam Usage
High beam usage is governed by law in most regions. For example, in the UK, the Highway Code states you must switch to low beam when there’s oncoming traffic, when following another vehicle, in built-up areas, or in poor visibility.
Similar regulations exist in the US, where most states require switching to low beams within 500 feet of an oncoming vehicle and 200-300 feet when following another vehicle.
Automatic high beams help drivers adhere to these regulations by proactively switching to low beams in the mandated situations. This can reduce the risk of tickets or accidents due to improper high beam use.
What Vehicles Have Automatic High Beams?
Automatic high beams first appeared on luxury vehicles in the late 2000s and have rapidly trickled down to more mainstream models since then. As of 2024, auto high beams are available on a wide range of vehicles from economy cars to pickup trucks.
Some automakers offer auto high beams as standard equipment on most trim levels, while others bundle it with other driver assist features or offer it as an optional extra. Here are a few examples of current vehicles with auto high beam availability:
Standard on Most Trims:
- Toyota/Lexus: Auto High Beam standard on nearly all models as part of Toyota Safety Sense/Lexus Safety System+
- Honda/Acura: Most models equipped with Honda Sensing/AcuraWatch
- Mazda: Auto High Beam standard on most models
- Hyundai/Kia/Genesis: Standard on most models with Smart Sense/Drive Wise
Optional or Bundled with Driver Assist Packages:
- Ford/Lincoln: Available as part of Co-Pilot360/Lincoln Co-Pilot360
- Chevrolet/GMC/Cadillac: Offered with Driver Alert Package, Driver Confidence Package, etc.
- Nissan/Infiniti: Select models with ProPILOT Assist or Safety Shield 360
- Subaru: Available with EyeSight Driver Assist Technology
- Volkswagen: Equipped on select trims or with IQ.Drive packages
Luxury Makes:
- Audi: Standard on most models as part of Driver Assistance packages
- BMW: Intelligent Auto Highbeams available on many models
- Mercedes-Benz: Active Multibeam LED with Adaptive Highbeam Assist Plus
- Volvo: Active High Beam standard on many models
- Jaguar/Land Rover: Auto High Beam Assist on select models
This is not an exhaustive list, and availability may vary by country and model year. In general, automatic high beams are becoming increasingly common, even on entry-level vehicles, as part of the industry trend toward more standard active safety features.
If auto high beams are a must-have feature for you, check the specifications carefully when shopping for a new vehicle. The feature may be marketed under different names like “Intelligent High Beams”, “Dynamic High Beam Control”, “Automatic High Beam Assist”, etc.
Are There Any Limitations of Automatic High Beams?
While automatic high beams are a fantastic convenience and safety aid, they’re not infallible. There are some situations where the system may not perform optimally:
Inclement Weather
Heavy rain, snow, or fog can trick the camera into thinking there’s an oncoming vehicle due to the scattered light from the precipitation. This can cause the system to switch to low beams unnecessarily. Fortunately, most auto high beam systems have a manual override that lets you force low beam mode in these conditions. You should always use your low beams in fog or heavy precipitation anyway to minimize glare.
Winding Roads
On very twisty roads, especially in hilly terrain, the camera may lose sight of a vehicle ahead as it goes around a bend. This can cause the high beams to switch on until the vehicle comes back into view, potentially dazzling the other driver. More advanced systems with stereoscopic cameras and predictive algorithms can better track vehicles through curves to avoid this. But it’s still something to be aware of on winding rural roads.
Motorcycles and Bicycles
Smaller vehicles like motorcycles and bicycles have dimmer lights and a narrower profile than cars. This can make them harder for the camera to detect, especially at a distance. While auto high beam systems are designed to err on the side of caution, it’s possible they may not dip for an approaching motorcycle until it’s quite close. Motorcyclists should be prepared for this by not staring directly into oncoming headlights.
Dirty or Obstructed Camera
The forward-facing camera needs a clear view of the road to work properly. If the windshield is dirty or foggy in front of the camera, or if there are large cracks or stickers obstructing it, the auto high beams may not function correctly. Most systems will alert the driver if the camera’s view is compromised.
Keeping the windshield clean, repairing cracks promptly, and avoiding placing items in front of the camera will ensure optimal performance. Despite these limitations, automatic high beams still provide a significant convenience and safety benefit in the vast majority of nighttime driving situations. As camera and processing technology continues to improve, these edge cases will likely become even rarer.
Proper Maintenance and Usage Tips
To get the most out of your automatic high beam system and ensure it operates safely and effectively, follow these tips:
Keep the Windshield and Camera Clean
Any dirt, debris, or moisture on the windshield can interfere with the camera’s ability to detect other vehicles. Make sure to regularly clean the outside and inside of the windshield, paying special attention to the area in front of the camera. In winter, be diligent about clearing snow and ice from the windshield, and use your defrosters to eliminate any fog or condensation that could obscure the camera. If your windshield fogs up frequently, consider using an anti-fog treatment.
Avoid Obstructing the Camera
The camera needs an unobstructed view of the road to work properly. Avoid placing stickers, decals, or other items in the area of the windshield where the camera is located. If you have a dashcam or portable GPS unit, make sure it’s not blocking the camera’s field of view. Even hanging air fresheners or fuzzy dice can be problematic if they swing in front of the camera.
Repair Windshield Cracks Promptly
Cracks or chips in the windshield, especially in the camera’s line of sight, can distort the camera’s view and cause problems with the auto high beams. If you notice any damage to your windshield, have it repaired or replaced as soon as possible. In some cases, a crack near the camera may require recalibrating the system after repair. Consult your owner’s manual or dealer for guidance.
Be Aware of the System’s Limitations
As advanced as they are, automatic high beams aren’t perfect. Be aware of situations where the system may not perform optimally, such as heavy precipitation, winding roads, or when approaching motorcycles or bicycles. If you notice the high beams aren’t dipping when they should, don’t hesitate to manually override the system and switch to low beams. You can always reactivate the auto function when conditions improve.
Understand the Controls and Alerts
Familiarize yourself with how to turn the automatic high beams on and off, as well as how to manually override the system if needed. The control layout varies between vehicles, so consult your owner’s manual. Also, pay attention to any warning lights or messages related to the auto high beams. If the system detects a problem with the camera or encounters an error, it will usually alert the driver via a dashboard indicator.
By keeping the camera’s view unobstructed, understanding the system’s limitations, and being prepared to intervene if needed, you can enjoy the benefits of automatic high beams while still being a responsible and safe driver.
The Future of Adaptive Driving Beam Technology
While automatic high beams are a great convenience, they’re just the beginning when it comes to advanced headlight technology. The next step is adaptive driving beam (ADB) systems, which take the concept of auto high beams to the next level.
ADB systems use an array of LEDs or pixels in each headlight that can be individually controlled. This allows the beam pattern to be dynamically adjusted in real-time based on the presence of other vehicles, pedestrians, road signs, and more.
Instead of just switching between high and low beams, ADB headlights continuously adapt the beam pattern to provide optimal illumination without glare. They can cast a longer, brighter beam down unoccupied portions of the road while selectively dimming or masking the beam in the direction of oncoming or preceding vehicles.
This technology has been available in Europe and Japan for several years but has been slower to catch on in North America due to regulatory hurdles. As of 2024, the US has updated its regulations to allow ADB systems, paving the way for wider adoption in the coming years.
Some luxury automakers like Audi, BMW, and Mercedes-Benz already offer ADB systems in the North American market. As costs come down and regulations evolve, we can expect this technology to become more mainstream.
Looking further ahead, headlight systems will likely become even more intelligent and responsive. Integration with navigation data, road infrastructure, and vehicle-to-vehicle communication could enable headlights to proactively adjust based on upcoming curves, intersections, or traffic patterns.
Headlights may also incorporate additional sensing modalities beyond just cameras, such as thermal imaging to detect pedestrians or animals. Advanced LED matrix and laser headlight designs could allow for even more precise beam control and extended high beam range.
As vehicles become increasingly automated, adaptive headlight technology will play a key role in extending the conditions under which self-driving systems can safely operate. By optimizing visibility and minimizing glare, these smart headlights will help make our roads safer for everyone