Fog lights are important automotive exterior lighting components, though they are often overlooked because of their limited functions. Nevertheless, they are designed to improve visibility during poor lighting conditions, particularly during adverse weather.
This article explores the car fog lighting system’s purpose and practical use, and compares it with other car lights. Let’s get right into it.
What are Fog Lights on a Car?
Fog lights on a car are a specialized automotive lighting system designed to improve visibility during adverse weather. As the name suggests, they are particularly used during fog but also offer applications during heavy rain, snow, or dust. Unlike standard car headlights positioned higher on a vehicle to project light straight ahead, fog lights are mounted lower, angled downward to cast a wide, bar-shaped beam close to the ground.
Functions of Car Fog Lights
While not essential in clear weather, fog lights are engineered for specific applications during harsh weather. Below, we provide you with a concise overview of some of the primary roles of this lighting system and how it benefits safer driving.
Illumination in Poor Weather Conditions
As mentioned, the most significant application of fog lights is to provide increased illumination during poor weather conditions. Their wide beam and downward angle minimize reflection back into the driver’s eyes. Instead, this light carefully gets under the fog to allow the driver to see the road better, including the edges, lane markings, and potential obstacles, as they navigate the road in these harsh driving conditions.
Marks the Position of Your Vehicle
Beyond improving vision, fog lights make it easier for other drivers to notice your vehicle. Since visibility is reduced during harsh weather, the low-positioned lights act as visual markers, allowing oncoming vehicles to spot yours from a distance. The rear fog lights also serve this purpose; they help prevent the risk of head-on or rear-end collisions.
Note the Direction of Your Vehicle’s Speed
This function is more pronounced in the rear fog lamps. They help signal your vehicle’s movement to cars behind, such as during deceleration or braking. The glow of the rear fog light helps drivers understand that you are slowing down, even before the brake lights get engaged. Likewise, the front fog lights offer directional cues for oncoming vehicles, such as turning, especially when paired with the car’s steering or signal system.
When to Use Car Fog Lights?
While fog lights are essential for improving visibility and safe driving, they are not meant for constant use. This begs the question: When should fog lights be used? Their name already provides answers to this lighting component’s usage.
They are designed for use in low-visibility conditions, such as during fog. You should switch on the fog light when your visibility drops below about 100 to 150 meters, roughly the length of a football pitch. Besides, when there’s fog, other atmospheric conditions that’ll prompt the user of these lights include snow, heavy rain, dust, or sandstorms. When driving before daybreak at dawn or during other poor weather, you can always switch on this lighting component for better vision.
Types of Automotive Fog Lights
Like other automotive lighting systems, fog lights have different designs and placements and use various technologies. However, they perform the same functions regardless of their variations.
Below, we examine the different types of fog lights, based on position, light source, and color variations.
Front Fog Lights vs Rear Fog Lights
Front fog lights are fitted in front, low, on the front bumper, below the car headlights. In contrast, the rear fog lights are fitted on one or both sides of the rear bumper. The front fog lights emit a wide, bar-shaped beam that penetrates fog, rain, or snow, providing better visibility. It points down, preventing it from bouncing into the eyes of oncoming drivers. Instead, it allows drivers to see road edges, markings, and obstacles.
On the other hand, rear fog lights are brighter than those in the front, allowing drivers behind to notice the presence of cars in front in low-visibility conditions. These fog lights are essential for preventing rear-end collisions.
Halogen, LED, and HID Fog Lamps
The choice of light source has a significant impact on the lighting performance, efficiency, and lifespan of automotive lighting systems. There are three standard lighting options for automotive fog lamps.
- Halogen Fog Lamps: These are the most traditional and cost-effective automotive lighting options. They produce warm lights that are easy to replace, but not energy efficient, and less durable, reducing their use compared to newer technologies.
- LED Fog Lamps: LEDs are the most common automotive lighting option in modern vehicles because of their energy efficiency, long lifespan, and instant-on brightness. All the lighting technologies offer the most illumination with minimal energy consumption. Moreover, they allow for compact and creative designs, making them the go-to option for custom lighting solutions.
- HID (High-Intensity Discharge) Fog Lamps: As the name suggests, HID lights are incredibly bright and efficient. This feature makes them a more common option for headlights. However, when used in fog lamps, manufacturers must carefully design them to prevent excessive glare, which will be counterproductive in low-light conditions.
That said, we must emphasize that regional laws govern each lighting solution. For example, some countries restrict the use of HID fog lamps due to the risk of glare, while some vehicle classes are mandated to stick to LEDs.
Yellow vs White Fog Lights
The color variation of the fog lights can influence visibility and aesthetics, often causing a debate on which color is better. Yellow light has a longer wavelength and is less likely to reflect off fog, rain, or snow, reducing the potential for glare. On the other hand, white light provides more natural and widespread illumination. It matches the color temperature of modern LEDs, creating a seamless look. However, white lights reflect more in fog, but their brightness still provides the needed clarity.
Comparing Car Fog Lights to Other Vehicle Lights
Fog lights are a component of the vehicle’s robust lighting system, which includes headlights, tail lights, brake lights, daytime running lights, etc. While each light has a unique role in ensuring road safety and communicating with other road users, understanding the distinction between each lighting feature will help drivers use them properly. It may also benefit manufacturers’ designs of these lights.
Fog Lights vs Headlights vs Tail Lights
Car fog lights and headlights differ in their beam direction and intensity. Indeed, both lights occupy the forward position, around the bumper. However, the headlights’ design is such that they project the beam over a long distance, usually at a higher angle for better road illumination. This feature makes them best suited for general nighttime driving.
In contrast, fog lights typically feature a wide, flat beam angled downward. This design is beneficial since its purpose is not to see far ahead, but to illuminate the road immediately in front of the vehicle in low-visibility conditions.
On the other hand, tail lights, which account for the red lights located at the rear of the vehicle, signal the presence of a vehicle to traffic behind it, especially at night or in dim conditions. Therefore, unlike fog lights or headlights, which help the driver see, tail lights help the vehicle be seen.
Fog Lights vs Daytime Running Lights (DRLs)
Daytime running lights are low-intensity front-facing lights that activate when the vehicle ignition comes on. They enhance vehicle visibility during the day and make your car more noticeable to other road users. Therefore, they differ from fog lights that help improve the driver’s vision in low-visibility conditions.
Fog Lights vs Reverse Lights vs Brake Lights vs Hazard Lights
Reverse lights are white lights that activate when the vehicle is in reverse gear. Their function is to illuminate the area behind the car, alerting nearby pedestrians and drivers that the vehicle is backing up. Similarly, the brake lights are activated when the brake pedal is pressed. These bright red lights signal to drivers behind that the car is slowing down or stopping.
In contrast, hazard lights are flashing lights on both the front and rear of the vehicle used to indicate a temporary stop, roadside emergency, or cautionary situation. Regardless of visibility, they are meant to draw attention to a stationary or slow-moving vehicle.
Considerations for Fog Light Design and Customization
When designing or customizing fog lights, automakers must balance aesthetics, functionality, and regulatory compliance. Unlike general lighting components, fog lights require precision in beam control and placement to perform effectively in low-visibility conditions.
Components of Car Fog Lights for Design Optimization
Below, we discuss considerations that drive high-performing and complaint-free fog light systems.
- Reflectors: Reflectors help direct the beam of fog lights, ensuring the light hugs the road and minimizes glare. The reflector material and geometry are usually optimized to maximize light efficiency. Also, the contour shape can be optimized to improve the car’s aesthetics.
- Lenses: Like a typical headlight lens, the lenses focus, diffuse, or shape the emitted light. In fog light systems, lenses are engineered to help maintain a wide and flat beam. Manufacturers may optimize them for textured patterns or optical segments that enhance lateral spread while preventing upward light scatter.
- Beam Cutoff Lines: The beam cutoff line is the sharp boundary that prevents light from shining upward into fog or oncoming drivers’ eyes. Optimising these cutoff lines helps reduce glare and enhance road visibility.
Waterproofing and IP Ratings
Since fog lights are usually mounted low on vehicles, they get exposed to water, dust, mud, and debris. Therefore, robust waterproofing is essential. Manufacturers often aim for high IP ratings, such as IP67 or IP68, which ensure considerable resistance to water immersion and dust ingress.
Fog Lights Placement and Angle for Optimal Performance
Fog lights should be mounted low on the vehicle’s front bumper, often just above the skid plate or under the grille. Mounting the lights above this specification will increase the risk of potential light scattering, reducing visibility. However, manufacturers still have to optimize beam angles for optimum downward and outward projection of the lights, illuminating the area close to the vehicle to avoid upward spill.
Customizing fog lights for off-road or high-performance vehicles may include other features like angle tuning or beam width variation. Some car enthusiasts may also prefer dual-color LEDs that switch between yellow and white, enhancing visibility in diverse conditions.
Material Selection in Fog Lamp Manufacturing
Choosing the right materials for fog lamp manufacturing is important to ensure durability and performance. Each component of a fog light—housing, lens, reflector, and seal—must withstand harsh conditions, including extreme temperatures, moisture, and mechanical impact.
The common materials for fog light manufacturing include:
Polycarbonate
Polycarbonate is the go-to material for automotive manufacturing solutions because of its exceptional impact resistance, thermal stability, and optical clarity. In addition, it’s lightweight and easily moldable into complex lens geometries, making it ideal for custom and high-performance fog lights.
PMMA
PMMA, commonly called acrylic, is another excellent material for crafting fog light lens covers, housing, and diffusers. This industrial-grade plastic possesses good optical features, allowing for excellent light transmission and clarity. When used as an enclosure, it gives a glossy finish, thereby enhancing the overall car aesthetics.
Aluminum
Aluminum is typically used for the fog lamp housing or heat sink. It provides excellent thermal conductivity, allowing efficient heat dissipation and prolonging the life of internal components. Also, it is corrosion-resistant, improving the parts’ structural strength, making it suitable for both standard road vehicles and rugged off-road models.
ABS
Like polycarbonate, ABS is a common plastic for fog light housings or support brackets due to its lightweight, cost-effectiveness, and good mechanical strength. It’s easy to mold, making it suitable for producing fog light components in high volumes. Because of its excellent surface finish quality, ABS is also suitable for secondary enclosures and trim pieces.
Seals
Seals are critical in maintaining the integrity of fog lights against moisture, dust, and pressure changes. Depending on the application’s temperature and environmental demands, these are usually made from EPDM rubber, silicone, or neoprene.
Proper sealing prevents condensation build-up, which can obscure light output and damage internal electronics. In addition, high-quality seals also ensure the fog light achieves a high IP rating.
Manufacturing Processes for Fog Lights
High-precision processes are necessary to ensure the desired specifications are achieved in the manufacturing of fog lights. Below are the common methods for creating fog lights.
Injection Molding
Injection molding is one of the go-to processes for creating automotive lighting systems out of plastics. The process liquefies plastics and polymers at high temperatures, followed by forcing them into a pre-designed mold cavity, where they cool and solidify into the desired shape. Automakers use injection molding to create the lens and housing of fog lamps, including those with intricate shapes and complex features.
CNC Machining
CNC machining involves controlling sophisticated machines using computer programs and software to cut through workpieces. The tools cut through various materials, including metals and plastics, to create desired shapes and structures for fog lamps. Auto makers primarily use this technique for prototyping and low-volume manufacturing of heat sinks and enclosures of fog lamps. Because of their tight tolerance specifications, CNC services are excellent for custom solutions that best suit car enthusiasts’ desires.
Vacuum Casting
Vacuum casting is another practical technique for prototyping and short-run production of DRL components, particularly when testing new lens designs or enclosures. It allows automakers to use polyurethane resins that mimic industrial-grade plastics like ABS or acrylic. However, unlike most casting techniques, the vacuum process allows the creation of bubble-free parts with excellent surface finishing. Therefore, manufacturers can create parts with accurate visual and functional testing before full-scale production begins.
Custom Vehicle Fog Lights and Other Automotive Lighting Solutions
WayKen specializes in custom vehicle fog lights and a range of automotive lighting manufacturing solutions tailored to your specific needs. From precision-machined fog light housings to complete lighting assemblies, our machining services ensure performance, durability, and visual appeal. Partner with us to bring your automotive lighting designs to life with precision and quality.
Conclusion
Fog lights are more than just auxiliary automotive lighting features; they are a targeted solution for enhancing driver visibility in adverse weather. However, they may integrate bright designs to boost the car’s aesthetics. In fact, some car enthusiasts may customize these fog lights using innovative technologies for better branding beyond the general improved visibility functions.
FAQs
What is the fog light symbol on my dashboard?
The symbol for the fog lights is an oval-shaped lamp with lines on its sides. When the front fog lamps are on, three diagonal lines intersect with a wavy vertical line to their left. For the rear fog light, the fog light symbol has three horizontal lines intersected by a wavy vertical line on its right.
Can I install aftermarket fog Lights on my car?
Yes, you can install an aftermarket fog light on your car. However, you must select lights that meet legal brightness, placement, and use requirements. Therefore, you should partner with an expert service provider when looking to customize or install your vehicle fog lights.
How do manufacturers customize fog lights for different vehicle models?
Manufacturers typically customize fog lights by creating CAD designs that suit the customer’s specifications, branding requirements, and vehicle models. It includes customizing the beam pattern, lens optics, mounting points, and housing shape.
