rear defroster

[Laura]

Haven't been on in a while, so I thought I'd come back with a mind-blowing question. . . which is complete sarcasm. . . but how would one go about fixing the rear defroster? My top 7 lines work, but the bottom 8 do not It drives me insane!

[kleinkid]

Sorry, can't help you. None of my lines work! Wish they did though. Hope you get some good answers so I can fix mine also. Isn't this electrical?

[entirelyturbo]

Yeah it is electrical. Wish I could help too. I'm fortunate that all mine still work.

*knocking on wooden desk*

[vrg3]

The problem in cases like this is usually that there's a tiny crack somewhere in the line. You can test it with a voltmeter.

Connect the negative probe to ground, and wrap a little piece of aluminum foil around the positive probe so that you can press it against the window.

One end of each line will read about 12v. The other end will read about 0v. If you run the probe from the 12v side to the 0v side of a properly functioning line, you'll see the voltage change smoothly from 12 down to 0. If you do it with a line with a crack in it, it'll read 12 until the crack and then 0 after the crack.

Once you find the crack you can repair it with a little bit of conductive paint that you can buy at an auto parts store made for this purpose.

[dropdfocus]

Excellent tip Vikash! I figured a continuity test would have been the only way, but I guess not. Although I've never gone looking for it, I don't think I've ever stumbled across the repair paint at my local Advance Autoparts. Of course Radio Shack should have something like that too.

[evolutionmovement]

It's like a copper-infused paint. You tape off the glass and paint it over the break in the line. You might have to ask for it, but it shouldn't be too hard to find.

[kleinkid]

It sounds like if your windows are tinted you can't do this fix?

[vrg3]

I don't know what causes the cracks. If they crack just due to age or sunlight or whatever, then yeah... you'd have to remove the tint film and then re-apply it after doing the repair.

If the crack was caused by something nicking the defroster, then it probably nicked a little hole in the tint too though. So you still might be able to locate the crack with the multimeter (you'll just look for a little spot where you can read 12 volts, since you won't be able to read the voltage elsewhere) and then paint right over it.

Maybe.