2006 Explorer rear window heater/defrost

Rear window defrost/heater does not appear to be working. Checked both fuses and relay all appear good and test light shows all window grid lines etc receiving electricity but will not clear/defrost rear window. Anybody have any thoughts on how this is possible? Could it be getting current but not enough to heat the defrost lines and if so what causes that or how to check/fix?

Something doesn't make sense. You say there are no breaks in the grid and the grid is getting power....it should work. Are you sure that there is actually power at the grid, and not just continuity of the grid? I had an individual grid line that wouldn't heat because there was a small break in the continuity of that individual line, but the rest heated ok. There is a kit to repair the grid lines, and the dealer fixed mine under warranty.

Well all I can say is that I have a 12v test light and it lights up when I touch all the grid lines and side grid where the electrical connects to window etc. The rear window does not defrost on any line, the rear defrost light lights up when pressed, and it stays on for a couple minutes then shuts off, just like it used to when it actually worked. I am stumped. A friend suggested that maybe it was not being ground properly or it was not recieving enough juice to actually make the grid heat fully but enough to make the test light come on. I don't know, I admit I have basic electrical knowledge.

Fixed mine.

I found the connection tab on the passenger side broke loose from the grid. I found a Permatex product that has conductive adhesive that will glue it back on. Soldering was not possible due to the tab being encased in plastic and all the plastic parts around it.

Tripdaddy said:

I found the connection tab on the passenger side broke loose from the grid. I found a Permatex product that has conductive adhesive that will glue it back on. Soldering was not possible due to the tab being encased in plastic and all the plastic parts around it.

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I had this same problem. The dealer charged me $140 to put it back on. :frustrate If I had any clue they would charge me that much I wouldn't have asked them to do it.

But do you think this could possibly account for test light still illuminating on every grid line when turned on if tab is off or barely touching??????

smcacc said:

Well all I can say is that I have a 12v test light and it lights up when I touch all the grid lines and side grid where the electrical connects to window etc. The rear window does not defrost on any line, the rear defrost light lights up when pressed, and it stays on for a couple minutes then shuts off, just like it used to when it actually worked. I am stumped. A friend suggested that maybe it was not being ground properly or it was not recieving enough juice to actually make the grid heat fully but enough to make the test light come on. I don't know, I admit I have basic electrical knowledge.

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The proper way to test this is by using a volt meter instead of a test light.
Measure from one side to the other of the grid. You should have around 12V maybe a little more with the engine running.
Then measure from one side to the center of each individual line. You should have around 6V.
If you get 0V or 12V you have a break in that line. These breaks can be fixed by an electrically conductive paint.

It is somewhat unlikely that all your lines would be broken at the same time, but see if you can do this test. This will also tell you if you have a weak connection as you would have less than 12V between the two sides.
A VOM meter is much better than a test light for this and can be had for around $ 5.00 at a cheap tool store. ($ 2.99 at Harbor Freight).

I'm having a similar problem on my '99 Mountaineer.

I disconncted one tab and put my meter in series with the circuit - it's getting 12 volts (13+, actually) but it's not defrosting. I'm going to check amps, next, to see how much current is flowing.

Are you testing the voltage between part of the grid and another part of the vehicle for ground (bare latch)?

Measure from one side to the other of the grid. You should have around 12V maybe a little more with the engine running.
Then measure from one side to the center of each individual line. You should have around 6V.
If you get 0V or 12V you have a break in that line. These breaks can be fixed by an electrically conductive paint.

What if you get 12v on every line and from one side to the other?

What if you get 12v on every line and from one side to the other?

Could be a ground issue.
When you use the tester you are probably completing the ground.
What I am trying to say is that the grid is getting power but its not going to ground completing the circuit and causing the elements to heat.
Not sure yet on how the explores are set up as I just got mine.
But generally the rear defroster grids on vehicles are set up one of two ways.
Either the grid is always hot (always have power) and the switch is the ground. or vice versa.
So you have to check continuity between both points and find out where the break in it is.
Hope you understand my ramble and good hunting

Tripdaddy said:

I found the connection tab on the passenger side broke loose from the grid. I found a Permatex product that has conductive adhesive that will glue it back on. Soldering was not possible due to the tab being encased in plastic and all the plastic parts around it.

Click to expand...

I just posted a question to this answer. How was this product for you? was it an easy fix with the plastic housing in the way?

Hey Matt,
Worked well. Since it was a while ago, I can't remember the details. I will say it was not too difficult.

BTW I grew up in Denmark WI just south of Green Bay. Glad I'm not dealing with the winter y'all (translation you guys) are having. We are having major ice problems down here this year.

Nice to meet ya! small world I work In Wrightstown just outside GB. Yes its been mighty cold this year, fortunately no ice just a lot of cold and snow and unfortunately its been to cold to properly apply a product like this as I don't have a heated garage....but anyway I will look into when the weather gets warmer. Thanks again