97 Bird: Rear Window Defroster

Hey guys, got a '97 V6 Firebird with a non-working rear window defroster. It flat out will not turn on; I can hear a faint click when I press the button in, but no light or defrosting going on.

Things I've done in attempting to fix the problem:

-Disconnected the connections at the rear window and tried to turn the defroster on.

-Swapped the circuit breaker for the rear defroster out for a different (same amp rating) one on the fuse block (think it was the one for the power windows). Also checked the HVAC fuse, which is still good.

-Took the HVAC panel off to get a look at the switch itself. What surprised me was that it's not a self-contained plastic module; it's a circuit board housed within the panel. I took the board out, resoldered some iffy-looking connections, and put the whole thing back together, to no avail. (I got this idea from fixing my BCM when my radio started cutting out. :biggrin:)

My next thought is to test the wires leading to the switch for power. Anyone have any idea what sort of voltages I should be getting, and across what terminals? I know I can always just replace the whole HVAC panel and be done with it (apparently you can't get just the defroster switch) but I'd like to make sure that the switch is actually the problem before I do that, and that there's no way I can't just repair the switch by replacing components on the board.

Any other ideas or insight would be greatly appreciated.