It is a know issue that most of the Volvo P80 cars built from 1998 through 2003 have headlights that deteriorate and once bad will project little or no light on the road. The solution is to purchase new headlights or install better lights, these Jewel headlights that Volvo installed on some 2003 and all of the 2004. There are two manufacturer of these lights, the original OEM Volvo/Hella lights or the after market lights, both are good options.
NOTICE: This pair has mild damage on the reflector and the backing on the left one has a chuck missing. I will get a replacement backing and ship it to the buyer once I get it. I think someone installed after market high output bulbs in them which caused the mild damage on the reflector. I believe these are still 10 times better than old dim lights.
The lights that I have for sale are good used lights. I have no idea how old they are because the label tag is likely worn off. They are probably dirty but have no damage. When you get them, install and use them, or clean them before you install them. I DO NOT recommend you take the lens off and mess with the silver reflector at all. That is the best part of the lights and if you damage that part, they will also be bad.