Why does my headlight look yellow and dull?
Modern headlights are made from a very durable plastic called polycarbonate, which is much more resistant to breaking than traditional glass. The downside of polycarbonate is that, over time, it can oxidise and start turning yellow due to constant exposure to the sun’s UV rays. To prevent this, manufacturers apply a UV protective coating to the headlight when the vehicle is produced. However, as the years pass, dirt, road grime, and chemical contaminants build up, while small stones and road debris gradually wear down this protective layer. Once the UV coating begins to deteriorate, the polycarbonate underneath becomes exposed. This is what causes headlights to turn yellow, cloudy, and lose their original clarity.
