Rear defroster not working -

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Old 11-17-2013, 12:36 PM   #1
3rd Gear Member
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Join Date: Nov 2007
Posts: 548
Question Rear defroster not working

Okay, I did a search and cant really seem to find anything so here goes

2003 GT Deluxe 106k miles. Rear window tinted.

I noticed last week my defroster wasn't working, although the light on the button is on. I went out back and looked at the copper leads that connect to the grid and they were corroded so i went to unplug the connector and broke one of the leads off of the window. Long story short i got the permatex kit and fixed it and reinstalled the tab and cleaned the other one carefully this time.

*the grid is complete and the tint has been there for years so nothing has changed since it last worked last winter.
*the maxi fuse in the pdc is good
*the button lights up when pressed

the only observation i can provide that seems different than i can ever recall is that when i press the button on or off, you can hear the relay under the stereo clicking

any advice would be greatly appreciated as ny winters suck lol
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Old 11-18-2013, 05:26 PM   #2
Doctor Defroster
Join Date: Nov 2013
Location: CO
Posts: 2

While it would be unusual if the defroster tab was still attached to the window and not making a good contact although we have seen repairs done with 'that other brand' which are non-conductive but well bonded to the defroster.

If you have a volt meter verify that the tabs are electrically connected to the defroster. Test directly on the metal base of the tab and on the defroster material next to the tab. With the defroster on you should see almost no change in voltage between the two test points at 12.5 volts or so (13.5 of so with the car running). There should be almost zero resistance between these two points.

Another way to test is the hot hand test. Turn on the defroster and then put your hand on the glass over the repaired tab. Be careful as this can get VERY hot if there is not a good electrical bond to the defroster.

If there is a sharp drop in voltage between the tab and the surface of the defroster this means there is a bad connection between these two critical parts. We like the Frost Fighter Tab Bonding Kit to bond these tabs back to the defroster because it is easy to use and is highly conductive. See

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