The rear defroster on my 92 EX 4-door does not work anymore. The push button illuminates, and I checked the fuse, but it does not defrost the rear window. Any ideas before I spend $$ on a mechanic to find something that I overlooked?

 

The lines on the rear window are one continuous circuit. One of the lines on the window might have gotten scratched off somewhere. I'd start by searching every inch on the defroster lines and repairing any that look damaged or broken. You can get a repair kit at an auto parts store. It's just a tube of a paste-like conductive stuff.