Hi everyone,

My rear window defroster doesn't work. The heated mirrors do work. I asked my Volvo mechanic and he checked that it is getting power. I was going to check the individual wires myself, instead of paying the shop by the hour. But, my husband tried to check the wires with a multimeter and found that there is a plastic coating on the inside of the rear window. He couldn't get any readings at all.

Is the plastic coating normal? Any suggestions on trying to find the wire(s) with the break?

TIA,
Linda
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The only reason for plastic coating is aftermarket UV protection. Unless you park outdoors in the summer, you don't need it. It can be stripped, but be careful not to damage the wiring.

Klaus
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98 V70Rawd(101Kmi), 95 854T(85K mi), 75 164E(173K mi)

Mine did not work neither. When you said the Volvo mechanic told you that the defroster got the power, where did the Volvo tech check for the power ?? Did he remove the tailgate trim panel and check the power at the positive & ground connectors ?

I removed the tailgate trim panel and found out that the ground connector was melted inside. I could see the melted plastic until I disconnected both the +12V connector and ground connector. Then I saw the melted plastic connector and the terminal burnt terminals inside the melted connector. I ordered the metal terminal (female one, male one was still in good shape), and the 2 plastic connectors from dealer. Now, the defroster is back to normal. However, it is still not as hot as new. The voltage I measured between the 2 connectors (+12V, and ground) was about +10V, not +12V. There is still some voltage loss along the path between the battery in the front of the car and the +12V connector of the defroster.

At least, it is working, but not as fast as new :-(

The "plastic coating", did you mean the reddish brown color on each defroster wire ?? The reddish brown color is not plastic .... You should be able to get reading from the wires.

Ching-Ho Cheng
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1995 855 NA, Bilstein Strut & Shocks, Volvo Protective Grill, K&N Filter, E-Code Lens, ClearCorner Light, Alpine CD-Changer, AutoDim RearView Mirror, 6000K HID