How to stop your headlights turning foggy and yellow

By Ryan Lewis, 23 May 2017 Car Advice

Buying new? We'll match you to the lowest dealer quote, get the best price for your trade-in and the lowest rate finance. Save thousands. Get started here.
Buying new? Get the lowest dealer quote, best price for your trade-in and lowest rate finance. Save thousands. Start here.
How to stop your headlight lenses turning foggy and yellow

Modern vehicles are plagued by unsightly, clouded and yellowing headlight lenses on an enormous scale. Not only are they ugly, they’re also unsafe. Here’s how to minimise the issue with your own car and how to fix the problem if it has already happened.

PROBLEM

As a car is exposed to the elements, ultraviolet rays from the sun break down the external coating on the outside of headlight lenses, and the ugliness sets in. The problem is particularly prevalent in Australia due to the harshness of our weather.

Foggy headlights look sad and can reduce your vehicle’s resale value. They’re also dangerous as cloudiness in front of the headlight bulb reduces its light output and makes driving at night more difficult.

Older cars with glass lenses don’t suffer from this condition, but most modern vehicles have lenses made from plastic for better pedestrian crash safety and more economic manufacturing.

PREVENTION

Thankfully, there are ways to prevent faded headlight lenses and to repair headlights that are already suffering from this condition. The simplest method is parking your car undercover, or in shade, with headlights facing away from the sun.

Keeping your car clean also helps. Contaminants in the air and grime from the road can speed up the oxidisation process. Properly cleaning your car on a regular basis is a useful precautionary measure.

undefined

REPAIR

Many car detailing companies offer a headlight repair service to make the process as simple as possible. Most will have a preferred method for dealing with it and can have your car fixed and back to you within a day or so.

If you’re handy, do-it-yourself kits for repairing foggy lenses are available from auto parts stores. Not all are created equal, but they all follow the same basic process.

undefined

First, the damaged layer must be sanded back to remove the fogginess. This needs to be done in stages, gradually working down to very fine, wet sandpaper before polishing and waxing the headlights to get them looking as good as new. 

The last step is to apply a new coat of UV resistant sealant. All headlights have a similar coating from the factory, but the sanding process takes this away. Failure to reapply it will see the headlights cloud over again in next to no time. This is also the case if you use other abrasives to remove the foggy layer, such as toothpaste or brass polish.

Different repair kits make various promises about their effectiveness. In most cases you will get what you pay for, but look for reviews on each before making your selection.