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Discussion Starter #1
The rear defroster button isn't lighting up anymore and the defroster doesn't look to be working.
The ECT button lights up and the hazard button works.
Can the switch itself go bad?

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Yes the switch can go bad, but that is rarely a problem.

First you need to know if it is just a problem with a burnt out bulb in the switch, or if the rear defogger is truly not working.

On each side edge of the rear window you should see some wider traces that all the horizontal grid-lines connect to. On each of these wider traces you should find some braided copper straps soldered on. Turn on the defogger at the switch, and use a multi-meter to measure the voltage between the 2 braided straps. If the voltage is 12 volts, the the defogger is working and you just have a burnt out indicator bulb in the switch.

If you don't read 12 volts, then check that the 10 amp "GAUGE" fuse is not blown.

This fuse doesn't supply power to the rear window grid, but it does power the indicator light, and the "DEFOGGER RELAY" which in turn sends power to the rear window.
 

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Discussion Starter #3
Yes the switch can go bad, but that is rarely a problem.

First you need to know if it is just a problem with a burnt out bulb in the switch, or if the rear defogger is truly not working.

On each side edge of the rear window you should see some wider traces that all the horizontal grid-lines connect to. On each of these wider traces you should find some braided copper straps soldered on. Turn on the defogger at the switch, and use a multi-meter to measure the voltage between the 2 braided straps. If the voltage is 12 volts, the the defogger is working and you just have a burnt out indicator bulb in the switch.

If you don't read 12 volts, then check that the 10 amp "GAUGE" fuse is not blown.

This fuse doesn't supply power to the rear window grid, but it does power the indicator light, and the "DEFOGGER RELAY" which in turn sends power to the rear window.
What do I set the multimeter to?
I have one but I a n00b.
All the fuses looked ok.

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Voltage DC- usually has a "V" with a strait line for DC, V and a sine wave for A/C voltage. Or you could read the instructions.
 

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Here you go:

 

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Here you go:
Watched the video. One mistake at 5:30. "If you don't hear the beep that means you have a short..." Not true, it means you have an open (no connection), the opposite of a short. The confusion is compounded by many electrically illiterate (okay, challenged) people calling anything wrong a short as in, "There must be a short somewhere."

Also be VERY careful when measuring Amps. If hooked up wrong you can easily smoke your parts or your meter.
 
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If your model has a timer, it would be in the switch. Both style switches use the same connector, only the switch is different.
 
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