A car with dim headlights is dangerous for both you and other drivers. If your headlights aren’t as bright as they used to be, then now is the time to discover why they’re dim.
Several things can cause dim headlights, and sometimes, getting new headlamp bulbs is enough to fix the issue. However, before you go out and buy new bulbs, it is a good idea to cross out other possible reasons why your headlights are dim.
What Causes a Dim Headlight?
Headlights become less effective with time due to many factors, including wiring issues, rusted ground connections, and faded/burned-out lamps.
In addition to this, old bulbs can film over as they burn, creating a gray/brown coating within the bulb. In fact, this grey/brown film can block 50% of the light emitted from the bulb at the end of the bulb’s life span!
If you are looking to fix your headlights that are new but dim, check for issues with ground connections and headlight lenses. If one or both headlights start to flicker while you drive over bumps, this indicates a problem with a corrosion connection or a bad wiring connection.
5 Steps To Repairing A Dim Headlight
If you feel that your headlights look like a flashlight that has lost its charge, then you’d better fix them. Before doing this, however, you will want to investigate what may be causing the problem in the first place.
Many times, drivers believe that the cause of the fading headlight is a poor connection to the power source. In actuality, in most cases, this is simply due to corrosion in the wiring.
Corrosion is accelerated by repeated exposure to the elements and heat. Replace the corroded wiring by disassembling the light assembly and replacing the damaged connectors.
- Disassemble the dim headlight.
- Trace the wiring harness from the back of each headlight to locate the corroded areas.
- Grab the wire brush and clean the ground cable connection.
- Apply dielectric grease to prevent future corrosion.
- Safely resemble the headlight and check the brightness.
The five-step process seems straightforward. It is not purely about cleaning. If the ground cable has stopped being “hot,” you’re likely going to need more than just new cleaning supplies. Non-auto enthusiasts will require a bit more than reading the steps out loud to get a complete understanding.
5 Causes and Solutions for Dim Headlights
Headlight Problem 1: Burnt Out Bulb.
When your headlights are dim, dying, or burned out, the best thing you can do is replace the bulbs. Just like light bulbs in a house, headlight bulbs will have to be replaced eventually.
How do I know if I need new headlight bulbs? Besides the obvious visual indication of dimming from usual brightness, checking for a burned-out bulb is easy.
To check, park your vehicle somewhere safe, turn your headlights on, get out of the car, and see if both headlights are working well and brightly. When you see that one headlight or both of them have become dim, take your vehicle in for bulb replacement service.
Headlight Problem 2: Lens Oxidation
If you experience dim headlights, you may be surprised to learn that it is not necessarily caused by bad bulbs.
In fact, it is often due to the fact that the headlight lenses are made of a material that reacts chemically to the sun UV rays, namely acrylic, and through the oxidation process; the lenses will eventually become cloudy, foggy, or yellowed and prevent adequate light from being produced through the lens, causing a poor lighting effect even with perfectly functional new bulbs.
If this is the case, the solution is to take your vehicle to a headlight restoration service; using professional equipment and expertise, your vehicle’s headlights can be restored to their original clarity, and also protected from future deterioration through lens oxidation. You can read the complete guide to headlight restoration service on our blog.
Headlight Problem 3: Wiring Troubles
Wiring harnesses and fuses are part of the electrical system powering the headlight bulb(s) in many vehicles.
Wiring issues can result in dimming, flickering, or the absence of clear light. Although uncommon, they are possible if a person has previously tampered with the headlights or attempted any do-it-yourself (DIY) repairs.
The exact nature of wiring issues will determine what type of repairs will be needed. A knowledgeable technician will diagnose the issue and, together with you, will develop a repair plan.
Headlight Problem 4: LEDs vs. Incandescent Bulbs
Have you ever noticed blinding headlights from another vehicle? Even though many LED headlights can produce more light than conventional halogen lights, you may find that your halogen lights are diminishing newer LED headlights. That’s because LED headlights produce a very white light with bluish overtones that are not present in halogen headlights.
Another reason that LED headlights appear brighter than halogen headlights is that LED bulbs create a harsh light that shines directly into the driver’s eyes. Halogen headlights produce a softer light, which tends to be less harsh than LED light.
There are many other elements that may affect how brightly the light coming from your headlamp illuminates the road ahead, including the make/model of the vehicle, the type of headlight lens cover, the overall headlight shape, etc. As of now, it is too soon to know what negative or positive effects LED headlights may have on the way we drive.
- The pros: Some drivers favor the energy efficiency and longevity of LEDs. They may also provide more visibility on the road for drivers.
- The cons: Those opposed to LED headlights suggest that they cause more harm than good by creating a glare for other drivers, which could cause accidents and eye strain.
Regardless of your stance on LED bulbs, you can speak to your mechanic about alternative bulb options available for your vehicle if you are interested in brighter options.
Headlight Problem 5: Setting Configuration
Today, there are various lighting options that drivers can utilize. Dimming of your headlights or failure of them to work are two reasons to check your settings. Many of the newer headlights will adjust automatically unless set otherwise.
As you can see, many people have “set it and forget it” headlight settings. If someone bumps the controls accidentally or there is another person driving who adjusts them, most people do not check them after the change.
While obvious, many people have their fog lights on versus their regular headlights. An adjustment of the headlight settings will help correct this issue.