How To Clean Headlights on a Car or Truck
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How To Clean Headlights on a Car or Truck

By Andra DelMonico | April 28, 2021

When you first bought your car, the headlights looked crystal clear. Driving at night was easy with how brightly they illuminated the road ahead of you. But with age and wear and tear on the vehicle, you may struggle to see with the barely-there light created by foggy headlights.

Thankfully, all is not lost. You can restore the look of the car's headlights and make them clear again. There are several methods, and depending on the condition of your headlights, one or more of these methods can work.
Follow this guide and say goodbye to foggy headlights.

Why Are Headlights Foggy?

Most vehicles used to be equipped with glass headlight lenses, but that is not the case anymore. Car headlights have been made of polycarbonate plastic for decades now. While this makes them more durable and affordable to fix, they do have their drawbacks.

One of the most significant issues with plastic headlight lenses is that they are susceptible to oxidation. Exposure to UV rays causes the clear plastic to start yellowing and become cloudy. But it's not the headlight itself that is clouding. It is the UV protective coating that comes on your headlights that is clouding and yellowing. Once this happens, the headlights will not appear as bright to you or other drivers and pedestrians.

The Sandpaper Method

The most effective method for restoring the look of your headlights is with a sandpaper headlight restoration kit. It will come with several grades of sandpaper, gloves, masking tape, padded sanding block, isopropyl alcohol, clear coat, orbital sander, water, and a soft cloth. Plan to commit about an hour of your time; this isn't a process you want to rush. You can buy a complete kit or create one from scratch. This will require a 320-800, 1,000-1,500, and 2,500-3,000 grit sandpaper.

This method works because the lower grit sandpaper is rough enough to remove the damaged material of the outer layers. The coarse sandpaper also creates scratches in the plastic. The more fine sandpaper grades reduce the blemishes until they are so minuscule they are barely visible.

Stage One

Start by protecting your car's paint and plastics by generously taping around the headlights. Use the 320-800 grit sandpaper on your headlights by sanding in a left to right motion. The worse your headlights are, the lower the number grit you should start with. Do not worry about the headlights getting cloudier at this stage. Finish this stage by rinsing the headlight clean and using a clean cloth to wipe away any dust and debris.

Stage Two

Use the 1,000-1,500 grit sandpaper during this stage. Get the sandpaper damp and begin sanding in an up and down motion. Changing direction during this stage helps smooth out the micro ridges created during the last step with the sandpaper's rougher sandpaper. Finish stage two by rinsing the lens with clean water and wipe any remaining dust or plastic debris with a clean cloth.

Stage Three

The third and final stage of sanding requires you to use the 2,500-3,000 grit sandpaper. Get the sandpaper wet for a damp sanding. You will work in a left to right motion again. Do this until the headlight is smooth and you have gone over the entire headlight. Rinse with water after sanding and wipe dry with a clean cloth.

Stage Four

Once done sanding, it is time to polish. Use an orbital sander with either a sheepskin or microfiber pad. Add compound to the pad, making sure it is evenly distributed, and work the orbital polisher over the headlight lens. You should see the headlight start to look clear during this process. Use a clean cloth and the isopropyl alcohol to clean the headlights after you finish applying the polish.

Seal the freshly cleared headlights by applying a clear coat / UV protectant. It comes in either a spray or a liquid that gets wiped on. Always follow the application instructions provided by the product manufacturer.

The Toothpaste Method

One of the most popular DIY suggestions is to use toothpaste to restore your headlights. This idea is a logical one because toothpaste is mildly abrasive, making it effective at removing grime.

To clear your foggy headlights with toothpaste, you will need paste toothpaste (not gel), masking tape, and two clean cloths. Start the process by covering the area around the headlights with masking tape. Use one cloth to rub the toothpaste onto the headlights. Leave the toothpaste on the headlight until it starts to dry. Then rinse the headlight with clean water. Use the second clean cloth to buff the headlight.

One drawback of toothpaste is that it is no more effective than dish soap or traditional car detailing products. It will not remove the oxidation or address the UV damage.

The Vinegar and Baking Soda Method

Another popular DIY option is to use a cleaning solution consisting of baking soda and vinegar. This method is logical because household vinegar is effective at cutting through gunk, grease, and buildup. Vinegar is also environmentally friendly, making it safe for cleaning headlights in your driveway.

To try this method on headlamps, you will need microfiber cloths, car wash soap, distilled white vinegar, baking soda, and a spray bottle. Start by cleaning the headlights with soap and water and let them air dry. Mix two parts of distilled vinegar and one part baking soda and shake it up. Spray the mixture on a microfiber cloth and work it into the headlight. Keep adding the cleaning solution as you go. Rinse the headlight with clean, warm water and assess the cloudiness. If necessary, repeat the process of applying the mixture and rinsing until the headlights are clean.

Window Cleaner and Car Polish

You can use a glass or window cleaner that is safe for polycarbonate on your headlights. Pick the cleaner of your choice as ammonia-free formulas work just as well as ammonia options.

To try this method, you'll need microfiber cloths, masking tape, gloves, window cleaner, automotive polish, buffer, car wax, and a bucket of water.

Protect the car's paint and plastic parts with masking or painter's tape. Apply the window cleaner and let it soak in for a few minutes. Use a microfiber cloth to wipe the headlight clean.

Now that the headlights are clean, use a microfiber cloth to apply the polishing compound in circular motions. If you do not feel like putting in the elbow grease, a rotary buffer will also work. A buffer makes it easy to apply the polish evenly over the entire surface of the headlight. Always follow the manufacturer's directions when using the polish.

The final step is to apply car wax. That will help seal and protect the headlights to prevent future clouding.

How to Prevent Future Clouding

With clean and clear headlights, you will want to keep them that way. Exposure to UV rays will cause them to oxidize all over again. Dirt, gravel, soil, salt, and sand will also cause the surface to wear away. To protect the headlight lenses, apply a sealant or clear coat. It creates a durable barrier on the surface of the lenses.

Park your car in a shaded place out of direct sunlight. If you can't avoid the sun, consider using a cover. When cleaning the car, focus on the headlights to remove gunk, bugs, and debris.