Why Is One Headlight Dim and the Other Bright?

Why Is One Headlight Dim and the Other Bright

One bulb of your headlight may be dimmer than the other because of an improper installation, burnt-out light, etc. It is a common event where a single headlight of your vehicle loses its brightness where the other is completely fine.

We understand how frustrating that can be for a vehicle owner. If you are confused about what made your headlights dim, go through our article. There can be multiple scenarios and reasons behind it, and we tried to include them all below.

Using a Headlight That Is Too Old

When buying a headlight, you may have noticed that the product mentions a lifespan limit. It indicates how long the headlights will survive if you use them normally. No matter how carefully you handle it, the headlight will die out after the lifespan is over. Halogen bulbs are pretty short-lasting compared to HID that last for around 8,000 hours of usage. Meanwhile, LED lights can last as high as 50,000 hours. The best thing to do, when this happens, is to replace the old ones with a new pair of headlights. If you thinking to buy any 4×6 led headlights then check this article.

Lack of Enough Wattage

If you did not know, the headlight uses its wattage to produce the light beams. For LED lights, the chip converts the electric energy to light. Now, different headlight sizes are built differently, and they may require a set amount of wattage to function properly.

You might have installed two headlights from different brands and modified them to fit your headlight slots. One of them probably requires more wattage to work than what your vehicle provides, even though its size almost matches the housing. It’s why experts advise you remain cautious about both the size and wattage requirement when buying a new headlight.

Blown Headlight Fuse

Another common issue that can make your light dim is if its fuse gets blown. Keep in mind that the reason behind this problem can be one of the multiple scenarios, and you should check it thoroughly. It can happen because of-

  • Having an exposed or broken wire or other wiring issues.
  • Having a headlight with the wrong wattage requirement.
  • A faulty headlight.
  • The high beam bulb can be damaged or have any fault.

Except for the second one, the other issues may require you to contact an expert to fix them or do it yourself.

Wrongly Installed Headlight

It is almost similar to what we said in the last point, but there are chances that you may have made any mistake when installing the headlights. If one of your headlights has not fit the housing properly, it can wiggle when you drive. As a result, the beam may focus wrongly, which would seem like the lights have turned dim.

There can also be some mistakes during the wiring process. If you insert the low beam, high beam, or ground wirings to the wrong plugs, it can be the reason.

A Corroded Ground Wiring System

The root of the problem can be in the ground wiring. A ground connection with corrosion can make the light dimmer than what it used to be when you bought it. There is a solution to it, though.

All you have to do is check the wiring harness of the dim headlight. Trace it and find the spot where it goes inside the body of the vehicle. That is the place you need to clean. You can research the cleaning process or hire an expert to perform it.

Headlights Focused at a Wrong Angle

Most of us know how your headlight should be more pointed on the road instead of upward to avoid blinding the upcoming traffics. However, you should also be aware that if the light is pointed too much downward, its light will feel dimmed. While it is not actually dimmed, the light won’t be where it should be. Adjust the light properly, in that case.

Foggy Headlight

Fog and debris from the road can make your headlights foggy and oxidized. The built-up grime creates a barrier that blocks lots of light particles. As a result, the lights get dimmer. If one of the headlights is dimmer, it may not have been cleaned for a long time. You can easily clean foggy headlights with toothpaste, baking soda, or vinegar.

Read more: Headlights Keep Dimming?

Final Note

The risk of having a dimmed headlight is high, and it can even lead you to potential legality issues. If you find your vehicle having such a headlight, you should check for all the scenarios above and act accordingly.

In many cases, you may need to completely replace your dim headlight with a new one. Make sure to get a headlight of high quality and a long lifespan. We hope that our article will help you remove your confusion about having a headlight dimmer than the other.

Leave a Comment