E30 Rear Demister problems

[johna]

The rear demister on my 1990 318is doesn't work at all.

I have checked the obvious things like fuses and all is ok. When switched on their is 12V and ground to the element on the window.

Using a multimeter or 12V test lamp I cannot get any reading at all on any part of the element or 'bus bars'. I thought that although I don't believe my windows are tinted there might be some sort of coating on the window that might be preventing readings so I scratched back some of the element in an incospicuous part of the window and still no reading.

I can measure up to where the terminals are soldered to the window element but nothing beyond there on either side.

Any suggestions?