If your wipers aren't frozen to the windshield, does this do anything? The description in the manual is puzzling: "This feature is used to prevent ice from building up on the windshield and wiper blades." For one, it says on the windshield, but unless I'm mistaken it only works on that small incidental bit of windshield where the wipers are parked (below the driver's field of vision), so yes, technically ice is being melted on the windshield, but not the part we need to see through during driving. Secondly, to prevent ice from building up (rather than remove ice that has already frozen the wipers)? Is there some issue where previously free wipers can suddenly stick to the car while you're driving? How does this prevent ice from building up?
i have driven in weather where the windshield and wipers both start to accumulate ice, and the front defrost is almost useless, but it's rare around here
I haven't had wipers suddenly stick to the glass, but have had ice slowly accumulate on the wiper blades while driving, interfering with their wiping ability and leaving streaks on the glass. An inherited eye condition causes my eyes to prefer to focus on these streaks instead of the road beyond, so I have greater need to keep the glass clean and clear than do most people. Having some heated glass at the bottom of the wiper stroke, which has been below the defroster's reach on my modern vehicles, reduces or delays ice buildup both on that portion of the glass, and on the wipers. Older models with steeper windshields didn't seem to have this unheated section. My successful experience with this has been on our dozen-year-old Subaru. Wished for it on our mid-1990s Subaru, it would have alleviated some problems, though I had some success addressing it by moving the wipers arms a notch higher on the spline shafts, shifting the wipers to warmer glass. My 2024 RAV4 hasn't spent enough time in winter driving to notice if it works.
