What to Do When the Car Headlight Cover Turns Yellow?

1 Answers
Elaina
07/30/25 8:52am
You can use specialized polishing wax to grind and polish the yellowed headlight cover. Minor yellowing and patterns can be removed. However, if the yellowing is very severe, you will need to go to a 4S shop or repair shop for replacement. Below are the specific steps for grinding and polishing the headlight cover: 1. Wash with soapy water. Soapy water is alkaline and will not corrode the headlight cover. 2. Soak sandpaper of different grits in cold water for 10 minutes, then evenly wipe the headlight housing, grinding back and forth in one direction. Keep the surface moist and apply moderate pressure to avoid damaging the surrounding paint or decorative strips. Continue until pits or scratches are smoothed out. Wipe gently with a towel and check if the grinding is even. Once done, dry the surface. 3. Use sandpaper dipped in water to lightly grind away the aged layer of the headlight cover. Then, apply a layer of polishing agent and finally spray a layer of clear oil for protection. 4. Some car headlights come with a built-in UV protection coating, which may be damaged during grinding. Use UV sealant to prevent further UV damage to the plastic.
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