How to Clean Foggy Headlights

Article overview

• Learn what causes foggy, yellowed headlights and how they affect your nighttime visibility and safety.
• Explore simple at-home solutions and budget-friendly DIY kits that can help restore headlight clarity.
• Understand when professional headlight restoration or replacement may be necessary.

Have you ever been driving at night and noticed your headlights aren’t as bright as they used to be? Or maybe you’ve driven through rain or snow and struggled to see ahead—even with your headlights on. Then when you park, you spot a yellowish haze or cloudy film on the headlight lenses. That buildup can make it harder to see and be seen, which is dangerous. But why does it happen? And can foggy headlights be fixed?

Why do headlights get foggy or look cloudy?

Headlights are made of a high-density, shatter-resistant plastic. Though the plastic is durable, the surface is porous and susceptible to degradation due to several factors. Even with a protective UV coating, time and environmental factors will eventually wear them down. Over time, the dirty pores and scratches will give your headlights a yellowed, foggy appearance.

Here are the top reasons for foggy headlights:

• Dirt and debris get caught in the plastic pores
  Headlight lenses are made of porous plastic, which means tiny bits of road grime, sand, dust and other particles can settle into the surface over time. This buildup creates a dull, dirty look that blocks light from shining through clearly.

• UV light from exposure to the sun makes the plastic brittle
  Even though headlights come with a UV-resistant coating, constant exposure to sunlight eventually breaks down that layer. This leads to discoloration, surface cracking and a cloudy, yellowish appearance.

• Oxidation
  Just like metal rusts when exposed to air and moisture, the plastic on your headlights oxidizes too. Oxygen reacts with the plastic’s outer layer, forming a chalky or cloudy film that reduces light output.

• Chemical exposure
  Harsh chemicals from car washes, road salt and cleaning products can wear down the headlight’s protective coating and damage the plastic beneath. This speeds up the clouding and yellowing process.

• Direct heat from headlight bulbs
  The bulbs inside your headlights generate heat, and over time, that warmth can cause the plastic to dry out and warp slightly. Combined with other environmental factors, this can make lenses look foggy or distorted.

• Trapped moisture
  If the headlight seal is cracked or worn, moisture can get inside the lens. This leads to internal fogging or condensation, which not only affects visibility but can also damage the bulbs and wiring over time.

Safety concerns due to foggy headlights

Though they may seem like nothing more than a cosmetic inconvenience, cloudy headlights can be a serious hazard on the road. When the lens becomes cloudy or foggy, the amount of light it lets through can drop dramatically.

On a sunny day, this is no big deal, but if you’re driving at night or through the rain, your visibility could decrease by as much as 50%. This makes seeing the road difficult and inhibits others’ ability to see you, making accidents with vehicles or pedestrians more likely.

How to repair foggy headlights

There is good news! There are several DIY foggy headlight repair options. Make a quick trip to your local auto parts store or place an online order, pick up a restoration kit and follow the instructions. These kits range from $10-$20. If you’d rather use home remedies, there are supplies that you may have lying around your house that will do the trick. 

If you can’t find a repair kit or would rather try another method, there are other materials that you can use to try to remove the cloudiness of your headlights. They include:

• Baking soda or toothpaste
• Diet Coke in a spray bottle (The mild acid helps break up grime.)
• Dish soap
• Warm water
• WD-40
• Towels
• Soft-bristled brush

DIY tips to clean cloudy headlights

Follow the DIY steps below to bring your headlights back to life:

• Step 1: Protect your car, tape off your headlights. Masking tape around the headlights will help protect your car’s paint from the chemicals.

• Step 2: Apply cleaner to your headlights and wipe away any grit and grime that’s built up in the pores. Follow up with low coarse sandpaper to remove any remaining debris.

• Step 3: Spread an even layer of pasty baking soda or toothpaste across the plastic surface.

• Step 4: Let the paste sit for three to five minutes.

• Step 5: Remove the paste with your soft-bristled brush. If it worked, you should notice the discoloration lift as you scrub.

• Step 6: Rinse the residual paste with some water, then dry with a towel.

Professional help for foggy headlights

If you are dealing with extreme cloudiness, DIY solutions will be limited in their effectiveness and professional assistance may be required.

The cost for professional intervention ranges from $100-$150 per pair of headlights, but extreme cases could cost as much as $200. New headlight assemblies range from $200 to as high as $2,000 per set depending on the car make, model and headlight style, making the cost of a professional restoration ideal for those wanting better results, but not wanting to spend the extra money on new ones.

Though foggy headlights may not seem serious, over time, they will become a hazard. At that point, restoration may no longer be effective, forcing you to replace the entire assembly. If you start to see signs of fog, don’t wait, remediate.