Why are my LED Headlights Dim?

by Penglight | Date: 25th May 2024

Why are my LED Headlights Dim - Penglight

Have you recently noticed that your once brilliant LED headlights are now casting a dim glow on the road ahead? If so, you’re not alone. Dim LED headlights can be a frustrating issue for many vehicle owners, compromising visibility and overall driving safety. As technology has advanced, LED headlights have become a popular choice for their energy efficiency and superior brightness. However, even these efficient bulbs can experience a decrease in luminosity over time.

So, what are some common reasons for car headlights to become dim Before we start, it’s important to understand the various types of car headlights.

5 Common Types of Car Headlights

There are several common types of car headlights used in vehicles today. Here are 5 of the most prevalent ones:

  • Halogen Headlights

Halogen Bulb Car Heaadlight

Halogen headlights have been the standard in the automotive industry for many years. They use a halogen gas-filled bulb that produces light when an electric current passes through a tungsten filament. Halogen headlights are relatively affordable and easy to replace, they have high CRI (Ra=100) and even illumination, but they are less energy-efficient and have a shorter lifespan because of the severe heat generation. Also, halogen headlights produce a yellowish light color which is gradually being replaced in some modern vehicles.

  • Xenon/HID Headlights

HID xenon bulb auto car headlight

High-Intensity Discharge (HID) or Xenon headlights use a xenon gas-filled bulb that produces a bright white-blue light when an electric arc is created between two electrodes. HID headlights offer better visibility and illumination compared to halogen headlights, with a color temperature that closely resembles natural daylight. They are 3 time more brighter than the same halogen lights and have a longer lifetime. Xenon headlights are commonly used in current high-end residential vehicle models.

However, they require a ballast to regulate the high voltage required for operation. And, xenon headlights have a noticeable delay (taking 3-4 seconds to reach full brightness) and their penetration in rainy, snowy, or foggy weather is moderate (not as good as halogen lamps). They also have a more complex structure, requiring components such as lenses.

  • LED Headlights

LED Headlights

Light Emitting Diode (LED) headlights have gained popularity in recent years due to their energy efficiency and longevity. LED headlights use a semiconductor diode to emit light when an electric current passes through it. They provide a brighter and more focused light output compared to halogen headlights while consuming less power. LED headlights also have a longer lifespan, making them a desirable choice for many car owners. However, LED headlights have higher costs and are not easy to repair in the long term.

  • Adaptive Headlights

Adaptive Car Headlights

Adaptive headlights are a newer technology that adjusts the direction and intensity of the light beam based on various factors. They use sensors to detect the vehicle’s speed, steering angle, and ambient lighting conditions, allowing the headlights to pivot or swivel to provide optimal illumination around corners and curves. Adaptive headlights enhance visibility and safety, especially during nighttime driving.

  • Laser Headlights

Laser Headlights

Laser headlights are at the forefront of automotive lighting technology. They use laser diodes to generate an intense beam of light, which is then converted into white light by phosphor material. Laser headlights offer exceptional brightness and range, improving visibility in dark conditions. However, they are currently found in high-end luxury vehicles and are not yet widely available in mainstream cars.

Why are my Car Headlights Dim?

One of the primary causes of dim LED headlights is voltage drop. LED headlights require a specific voltage range to operate optimally, typically between 9 and 32 volts, depending on the specific LED headlight model and manufacturer’s specifications.

Voltage drop can occur due to various factors, causing the headlights to appear dimmer than usual. Here are a few common reasons for voltage drop in LED headlights:

  1. Aging or Faulty Wiring: Over time, the wiring in a vehicle can deteriorate, leading to increased resistance. This increased resistance results in voltage drops as the electricity encounters more obstacles while traveling from the power source to the LED headlights.Aging or Faulty Wiring of car headlights
  2. Inadequate Power Supply: Some vehicles may have stock electrical systems that do not provide sufficient power to drive LED headlights at their full brightness. This issue is particularly common when aftermarket LED headlights with higher power requirements are installed without upgrading the vehicle’s electrical system.
  3. Poor Grounding: Proper grounding is essential for the efficient flow of electricity. Inadequate grounding or loose connections can cause voltage irregularities and dimness in LED headlights.

In addition, the internal dirtiness of the lampshade, the use of inferior lampshades, and the aging and yellowing of the lampshade can also make your headlights dim.

  • Internal Dirtiness of the Lampshade

Over time, dust, dirt, and debris can accumulate on the inside of the lampshade, reducing the amount of light that passes through. This can lead to dim headlights. Regular cleaning and maintenance of the lampshade can help restore its transparency and improve light output. Use a soft cloth or a mild cleaning solution specifically designed for automotive lampshades to gently remove any dirt or grime. Be cautious not to scratch or damage the lampshade during the cleaning process.

  • Use of Inferior Lampshades

In some cases, the use of low-quality or substandard lampshades can result in dim headlights. These lampshades may not be designed to maximize light transmission, leading to reduced brightness. If you suspect that the lampshade quality is the issue, consider replacing it with a high-quality, OEM lampshade or one that is specifically designed for your LED headlights. Investing in a reputable and well-designed lampshade can significantly improve the light output and overall brightness.

  • Aging and Yellowing of the Lampshade

As time passes, lampshades can deteriorate and develop a yellowish or hazy appearance, mainly due to exposure to UV rays and environmental factors. This aging and yellowing can impede the light output and result in dim headlights. If cleaning doesn’t restore the clarity of the lampshade, replacing it with a new one is often the best solution. Opt for a lampshade made from durable materials that are resistant to UV damage and discoloration. This will ensure longevity and maintain optimal light output.

Among all the components, the most direct and fundamental reason for car headlights becoming dim is the aging of the bulbs.

Therefore, upgrading from halogen bulbs to xenon or LED bulbs can significantly improve the lifespan and brightness of your headlights. While halogen bulbs typically have a lifespan of around 6 months to 2 years, xenon bulbs can last approximately 5 to 6 years, and LED bulbs have an impressively long lifespan of over 30,000 hours.

When considering an upgrade, it’s important to ensure compatibility with your vehicle’s headlight housing and electrical system. Some vehicles may require additional modifications or adapters to accommodate xenon or LED bulbs properly. We suggest consulting your vehicle’s manufacturer or Penglight (one-stop lighting solution provider) to ensure a proper and safe installation.

What are some signs that indicate car headlight is aging?

  • Diminished Brightness

As headlights age, their brightness can gradually decrease. You may notice that the illumination provided by the headlights is not as effective as it used to be, leading to reduced visibility while driving at night.

  • Yellowing or Hazing

Over time, the plastic lens covering the headlights can become yellowed, hazy, or foggy. This can occur due to prolonged exposure to sunlight, environmental elements, or natural wear and tear. The yellowing or hazing can obstruct the light output, resulting in reduced brightness and clarity.

  • Scratched or Pitted Lens

Headlight lenses may develop scratches, pits, or other forms of damage as they age. These imperfections can scatter or block the light, diminishing the overall performance of the headlights.

  • Fading or Discoloration

Headlights may experience fading or discoloration, particularly in the case of plastic lenses. This can result in a dull or discolored appearance and can impact the light output and aesthetics of the headlights.

  • Moisture or Condensation

Aging headlights may be more prone to moisture or condensation buildup inside the lens assembly. This can occur due to worn-out seals or cracks in the housing, leading to reduced visibility and potential damage to the bulbs or electrical components.

  • Inconsistent Beam Pattern

As headlights age, the beam pattern they produce may become irregular or scattered. This can result in uneven illumination on the road, reducing visibility and potentially causing discomfort for oncoming drivers.