Symptoms
- Headlights look yellow, hazy, or foggy from the outside
- Noticeably dimmer headlights at night despite working bulbs
- Headlights look worse than the rest of the car's condition
Likely causes
- CommonUV exposure breaking down the protective clear coatSun exposure over years is the main cause, independent of how the bulbs themselves are performing.
- CommonOxidation of the plastic lens material itselfOnce the clear coat is gone, the underlying plastic yellows with continued sun exposure.
- PossibleRoad debris pitting adding to the hazy lookSmall pits from highway driving can combine with yellowing to worsen clarity.
What to do
- Wash the headlight area first to rule out simple dirt buildup rather than actual lens damage.
- If yellowing remains after washing, use a headlight restoration kit, which typically includes sanding pads of increasing fineness and a polish or sealant.
- Tape off the surrounding paint to protect it from the sanding and polishing compounds.
- Work through the kit's sandpaper grits from coarsest to finest, keeping the surface wet as instructed, then apply the polish.
- Finish with the UV-protective sealant included in most kits to slow the yellowing from returning as quickly.
- Repeat this every year or two, or consider a professional detail shop for a longer-lasting result.
Tools and parts
- Headlight restoration kit
- Painter's tape
Headlight restoration kitSearch: “headlight restoration kit”
When to call a pro
If restoration doesn't sufficiently improve nighttime visibility, or the lens is cracked, consider a professional detail or lens replacement.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.