Professional Headlight Restoration and UV Protection Guide (Jan 2026)

Wash the headlights thoroughly with a high-lubricity car soap to remove surface dirt, salt, and bug splatter. Use a clay bar if the surface feels gritty (common with red dust or industrial fallout). Inspect for internal moisture; if the fogging is inside the unit, this guide will not resolve the issue as the seal has failed.

Apply two layers of automotive masking tape to the paintwork, chrome trim, and rubber seals surrounding the headlight. In high summer heat, ensure the panels are cool to the touch before taping to prevent adhesive transfer. This prevents accidental sanding of your vehicle's clear coat.

Submerge your P800, P1200, and P2000 sandpaper in a bucket of water for at least 15 minutes prior to use. This softens the paper backing and ensures the abrasive particles are evenly lubricated, preventing deep, uneven 'pig-tail' scratches that are difficult to remove later.

Position the vehicle in a shaded, well-ventilated area. Never perform this on hot panels or in direct sunlight, as the lubricants will evaporate too quickly, leading to heat build-up in the polycarbonate which can cause 'heat checking' or permanent cracking.

Using the P800 grit paper and plenty of lubricant, sand in a horizontal motion. This is the most critical step as it removes the failed UV coating. Continue until the slurry turning off the lens changes from yellow (oxidised coating) to white (pure polycarbonate). The lens will look completely opaque at this stage.

Wipe the lens dry with a clean microfibre. Inspect for any remaining yellow patches or uneven texture. The surface should have a uniform, frosted appearance. If any spots look 'clearer' than others, you haven't removed all the old coating yet; repeat P800 sanding.

Switch to P1200 grit. Sand in a vertical motion (perpendicular to your previous step). This cross-hatching technique allows you to visually confirm when you have removed all the P800 scratches. Sand until only vertical scratches remain. Use light, even pressure.

Return to a horizontal sanding motion with P2000 grit. This stage begins to restore some translucency to the plastic. Spend at least 3-5 minutes per headlight at this grit to ensure the surface is as smooth as possible before moving to mechanical polishing.

For a professional finish, use a P3000 foam-backed disc. This further refines the surface, making the compounding stage significantly faster and reducing the heat generated by the polisher. The lens should start to look slightly clear when wet.

Apply 3-4 pea-sized drops of heavy-cut compound to a firm foam or wool cutting pad. Set your DA polisher to a medium speed (approx. 3000-4000 OPM). Work in a 50% overlap pattern. The heat generated should be warm to the touch, never hot. The lens will dramatically clear during this step.

Switch to a soft finishing pad and a fine polish. This removes the 'haze' left by the heavy compound and creates a mirror-like finish. Use lower pressure and slightly higher speed. Wipe with a clean microfibre to check for 'holograms' or micro-marring.

This is a non-negotiable step. Spray a 70% IPA solution or panel prep onto a microfibre and wipe the lens thoroughly. This removes all polishing oils and lubricants. Without this, your UV sealant or ceramic coating will fail to bond, leading to yellowing within weeks.

Apply your chosen UV protector. If using a ceramic coating, apply in small overlapping circles using a suede applicator. If using a wipe-on liquid sealant, apply in a single, smooth horizontal pass. Ensure 100% coverage, as any missed spot will oxidise rapidly in the sun.

Allow the coating to cure undisturbed. Most ceramic coatings require 12-24 hours of dry time before moisture exposure. Do not wash the car or drive in the rain during this window. In high humidity coastal areas, extend this time by 50%.