Headlight lens yellowing on Hyundai Elantra

Average mileage: 78,333 (50,000–125,000)
3 model years affected: 2000, 2001, 2005
3 people reported this problem
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problem details
This is more of a nuisance than a severe mechanical problem: my headlight lens both have filmed over. Light output to the road has decreased as a result. I checked out numerous headlight lens cleaners and polishers, but nothing guaranteed a solution. I saw that some kits contained a high grit sandpaper. I decided to experiment, as my lights couldn't get any worse, and used some Bon Ami on a wet cloth and rubbed the lens vigorously. It worked very well. Of course, I tried it out on a small section of the light prior to doing the entire lens. (by the way, I'm sure that Ajax would work as well as Bon Ami). I can now see the road again at night. The can of Bon Ami cost me about $1.60. I think it was a good deal.
2001 Hyundai Elantra 125,000 mi,
I bought car used, just replaced headlights from Rockauto.com, $45.00 each.