|Rear Window Defog Switch Relay___________________________|
Some Scorpios love to melt the rear defog switch; others don't seem to do this at all.
If yours is the former, before you replace the old switch, wire in some insurance so it doesn't happen again.
This is one of my cars (the other doesn't need it). The yellow box was a spare 4 prong generic relay (conveniently marked for correct wiring).
Here's the schematic: