Rear defroster 79 ta

[james.dowling99@yahoo.com]

Hello,I have a question concerning the rear defroster.
I removed my rear window due to scratches,  a lot of them.
I found a better rear defogger glass. The defogger grid has continuity.
I read voltage.  But it doesn't seem to get warm. My old one worked. I do not want to pay for an installation if this glass isn't going to defrost. What am I doing wrong? I am using an infrared thermometer Don't notice a temperature change. Any insight appreciated.

[Wallington]

You've tested both ends of the circuit to make sure power runs from wire to wire? The rear glass is basically like a giant fuse, live wire one end, ground wire the other and it heats up instead of blowing, based on the power input.

Did you only use a testlight or run some extension leads to test off car? One end for live power when turned on, the other end that normally ground near the parcel tray needs similar.

[james.dowling99@yahoo.com]

I first jumped it with battery, + to +, - to -. Then laid it in the car, connecting power and ground. It doesn't seem to heat up more than a few degrees. Did this w ignore on, and then with the car running. I Google what temp a defroster should reach, 85 deg is what I cam up with.  I'm getting mid 60s glass was upper 50's before powering up. Green light on Def sw is illuminated when I turn it on.

[jbanna]

I replaced my rear window about 30 years ago, with a junkyard one, and it has worked great ever since; however, I did have to repair a couple of the grids with a kit readily available at auto parts stores - if you do it right and test the resistance on the "unbroken" grids, you should have the same results - there can be breaks not easily visible...