Greetings all! I have come across a problem recently. Driving home from work last week, I turned on my rear window defroster and when I looked down again, it was off (few minute timespan). I tried it a few times and it would not come on.
I've tried a bit of troubleshooting with the wiring. Here's what I've done: First I changed out the relay. Doing some research, they said that even though the relay may still click, it might not work. Three of the five prong on the relay looked like they had seen some higher temperatures (semi burn marks). The relay did not fix anything.
I pulled the switch out and checked the light bulb to make sure that it wasn't just a burned out light. That checked good and ohmed good too. Checking power at the connector that plugs into the switch, (from right to left looking at it) the backlight pin (far right) shows 3.28VDC, the next one to the left shows nothing (which is the one I think draws power to the light when the defroster is on), the next pin to the left draws 11.47VDC and of course the one on the left is a ground.
I ohmed out the grid on the rear window and it was showing good at (I believe) 0.8 ohms.
Oh yeah, not to mention the fuse is good too. Believe me, that was the first thing I checked. I am also getting a constant 11.8VDC from the fuse too. Just to make sure I didn't have any broken wires from the fuse back, I checked the wires at the back connector (where it connects into the hard top) and it showed the same thing.
I also did pull the dashboard apart and checked to make sure the two wires going to the back of the dash were tight into the connector.
I'm at a loss here. I've searched online for wire diagrams and what not, but found nothing. If anyone has any information, it would be greatly appreciated. Thank you!
EDIT: By the way, I was checking this all out on battery power, not with the engine running. I took a quick reading and with the engine running, it was 14+ VDC