I keep my Prius Gen III in an outdoor parking lot and of course some mornings have ice on the windshield. I use an OXO plastic ice scraper and I am extremely careful with removing ice and almost never press hard to the glass. I try to remove the top layer and then use the front defroster to remove the rest of the ice. Lately I've been noticing faint scratches in the front windshield when the sun hits it which appear to be ice scraper marks based on the pattern of the scratches. Is the Prius Gen III windshield more succeptible to scratches than other makes? My prior car (Acura) did not do this and the side windows don't show any scratches, knock on wood....
Maybe you can try a light scrubbing pad (white, made for windows) and some car wash/foaming window cleaner to see if the marks come out. I'm thinking the rub marks are from the plastic transferring to the glass and not scratching the glass. Rub your finger over the scratch. If you feel more of a groove, then it may be a scratch. If you feel more of a bump, then it maybe the plastic rubbing off and sticking to a cold windshield. You mentioned ice on the windshield, I'm thinking the windshield is colder then the scraper and the difference in rubbing (friction) and temp of the windshield is causing the marks. I have heard of people waxing their front windshields to help ease in ice/snow removal. Since I do not live where it snows, I have never tested this out. However, I have waxed my windshield to help the water bead up from the glass when it is raining. This has helped the wiper provide better view during driving in the rain. Let us know what you find out and if you can "rub" out those marks. Good Luck!
Same wax I use on the paint. Just make sure you prep the window first. What I mean by that is getting all the bug splatter and other debris off of there first.
RainX is a good product. It is a chemical that sits on top of the glass to help repel the water. I used to use RainX until I noticed that it never leaves the glass completely clear/clean. I would see what I describe to be glare or beams when the sun crosses the glass. Cleaning the glass of dirt and grime and then waxing has left me with better results. Waxing the glass is almost like polishing the glass leaving it smooth. This is part of what helps repel the water. Just some thoughts!
