BrianL

Hello All. I believe I've figured out the reason why it doesn't work: IT'S 30 YEARS OLD!!! I replaced the rubber seal around the glass and thought that would also be a most favorable time to fix the defroster as well. I had planned to replace with new glass if I couldn't figure out or fix the defroster problem, and after calling several local auto glass shops as well as Motorsport, found out that replacing the glass is not really an option. When I had the glass out I was able to get a close look at the underside of the defrost lines in direct sunlight. They were (are) covered in black corrosion ( or 'stuff'). I carefully worked on a small section with steel wool and a razor blade; in some places I was able to find metal, but in others it was all black stuff. I have owned this car for about 6 years, and when I first got it the rear defroster worked, then after a year or two the orange switch busted. About another two years went by before I got around to replacing it (still didn't defrost) and now not a single line will carry a current. Weird. (Maybe it was those two lost years at Humboldt? Lots of rain up there…). The bottom line is it doesn't seem to be something that is fixable; although I had toyed with the idea of getting 'that metallic tape' one can use to fix small sections of missing defroster line and re-doing the whole rear window with it… I doubt it would come out straight, and my hands need to heal anyway.

I need some help with my rear defogger: The switch works, and power flows through the lines in the glass, but the rear window stays foggy in the morning. I have an old voltmeter and determined that around 5 V flows through the lines both from the glass to the ground (drivers side) and from the hot-wire (red-black wire on passenger side) to the ground. My Haynes shows that there is a 20A fuse between the glass and defrost switch, but since everything gets power that fuse must be intact. Will the glass physically heat up to the touch if it is working properly? Maybe I don't have enough power flowing through… If that is the case then maybe the lines are corroded somewhere along the way? Oh, also when I turn the switch on and off the ammeter in the dash shows no change. Any theories and/or ideas are appreciated. Solutions are welcomed as well! Thanks guys. -BrianL

I have had similar experiences with my 72 (stock engine). I would drive freeway speeds and the engine would cut out when at speed. To make a long story short, I finally figured out that the wires that connected to the ballast (that ceramic thing next to the coil) were being jostled loose when high winds (from those 'freeway' speeds) would pass by it. Zip ties and some electrical tape now keeps it from happening again. I hope this is your problem, because it's an easy fix! -Brian L.