Why can’t defroster wires be built into the windshield of my car as they are on the rear window?
Because it would obstruct your vision. There is probably a federal regulation against that. Off and on, Ford has experimented with something they called Insta-clear windshields. These has a fine coating of metal spread all through the windshield (so, no wires to see). They required high voltage to work. They were expensive and required either an extra alternator, or a complicated scheme to disconnect the single alternator from the battery and switch it to high voltage mode. I think they have given up on it.
They COULD be, but would you want to drive looking through a grid of wires?
As Tardis said, there were some heated windshields on Ford vehicles for a while. They look sort of red when the light hits them just right. I have to assume they were too troublesome, as they are no longer available to the best of my knowledge.
As long as your vehicle’s HVAC system is working correctly the windshield should not be hard to defrost/defog.
I would drive ok with wires in the windshield. But, alas, the laws say otherwise. Your subconscious will ignore them exacly as it does when you get bug splats in your field of vision; For the first few miles it’s odd but after that you don’t even notice.
I will also say why would you want them? The rear defoggers/defrosters are only really effective at clearing off liquid condensation and you’ve got windshield wipers to take care of it on the outside and even blowing cold air out of your defroster will evaporate anything on the inside pretty quickly. Next time you get a good coating of ice on your back window, see how long it takes for the defroster to melt it to a point it would be safe to look through while driving. It’ll probably take at least 5 minutes or so, probably only marginally faster than your regular old heater defroster will take up front. For the foreseeable future, you’ll probably need a garage to save you from the drudgery of scraping your windows.
I think they are that way on the Dodge Caravan (and its clones). You might notice a single defroster wire across the bottom of the windshield. Since heat rises and there are heater vents right there, that is probably all you need on the windshield.
If scraping ice is the issue, you should look into windshield covers that are being sold for this purpose. You put the cover on when you park the car, remove it before you drive, and you don’t have to scrape ice off the window.
No, I think you might be describing the same thing as I have on my Lincoln LS. It is a heated wiper park area. Its purpose is not to defog or defrost the windshield. Its purpose is to keep the wiper blades from freezing to the windshield.
They were pink looking out from the inside too. I was loaned a car for a day that had one of these and I felt like I’d spent the day looking through rose colored glasses. Like a monochromatic bad dream.
So that is what that thing is! Cool.