You may think that a broken wiring stud (or spade) connector on your rear defrost grid means that you will never have a rear defogger again. But the new kits have repair parts you can use to repair this and anything else wrong with your system. If you've tested your rear window grid and found a bad spade connector or stud, the first step is to get the old one off (if it's still hanging on) and clean the area under it. This can be done with the emory cloth included in your repair kit. Next mix up a little of the conductive epoxy and use it to reattach a new stud to the glass. Be sure you get it in the same spot as the one you removed. Allow it to dry for 24 hours and give your defrost a try.
Tip: It's also a good idea to have a circuit tester handy to be sure you have a proper ground for the system.