The headlights are fully factory fitted and require periodic maintenance. If you notice that the headlight housing has become obscured over time, or that the headlight has minor dust or other mechanical scratches, you can sand and polish it. This will help to restore the headlights to their original brilliance and ability to fully transmit light from light bulbs and reflectors. If this procedure does not help, it may be more reasonable to change the headlights to new ones.