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Old 11-28-2007, 03:38 PM   #1
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Default Rear window defogger question

Now that the cold weather is here I find that the rear window defogger isn't working. The switch lights up when pushed, but nothing happens on the other end.

Do the trim panels around the rear window just pop off so I can check connections?

I can't find a blown fuse, is there a relay under the hood?

Any other possibilities?

Thanks,
John
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Old 11-28-2007, 03:57 PM   #2
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Is the harness plugged into the heating element on the window? IIRC, it plugs in on the driver'* side.

If so, unplug it, turn on the switch and read the voltage coming out that harness. That will at least pin point where to start troubleshooting - at the window element, or before it in the harness.
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Old 11-28-2007, 04:00 PM   #3
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Do you hear a click from anywhere in the dash when you try to turn it on? There should be a relay click.
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Old 11-28-2007, 04:27 PM   #4
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Quote:
Originally Posted by J Wikoff
Do you hear a click from anywhere in the dash when you try to turn it on? There should be a relay click.
No, I do not hear a click. So, where is this relay?

I'm off to find the connector to check voltage. be right back.
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Old 11-28-2007, 04:27 PM   #5
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...and you should also see the volt guage drop, then come back up very quickly when you turn the switch on.
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Old 11-28-2007, 04:37 PM   #6
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I'll have to check my FSM for the relay location, but I think it'* one of the set behind the glovebox.
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Old 11-28-2007, 04:39 PM   #7
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Quote:
Originally Posted by vital49
...and you should also see the volt guage drop, then come back up very quickly when you turn the switch on.
I did look for that and there is no drop on the guage when I activate the switch.



I popped off the trim on the drivers side, seen a wire going down towards the trunk area, opened the trunk and could not find any sign of that wire. Where did it get to?

OK, I must admit that it was a quick look, it'* pissing down rain and I got no place to work under cover so any answer would be welcomed, the correct answer would be welcomed even more.
I only get the car when I'm off and the wife is working, maybe once a week if I'm lucky. Then when I do get it, it comes with a list of things to look at. :(
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Old 12-08-2007, 11:17 AM   #8
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JMH,

Did you ever figure this one out? I'm heading out to start trouble shooting mine. Whe I push the rear defog button I get a relay click and the light comes on, but nothing happens.

There'* another post here that'* really good I believe. I just have to find it.

Mike
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Old 12-08-2007, 07:45 PM   #9
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Quote:
Originally Posted by PONTIATTACK
JMH,

Did you ever figure this one out? I'm heading out to start trouble shooting mine. Whe I push the rear defog button I get a relay click and the light comes on, but nothing happens.

There'* another post here that'* really good I believe. I just have to find it.

Mike
Thanks Mike. No I haven't figured this out yet. When I push the button the light comes on but no click from a relay and no variation on the volt meter.

It'* on hold right now, I bought a set of FSM of Ebay, when/if they ever get here I can start tracking down stuff.
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