I don't have a wiring diagram but I've replaced the switch a few times because of this problem. It is very easy to get at. At the end of the following thread are a few pics from the last time I replaced it:
http://www.escape-city.com/viewtopic.php?f=8&t=10&st=0&sk=t&sd=a&hilit=moonroof+switch
There was a member here who said it was the contacts in the switch and there was something he applied that made it work fine. I'm not sure if it was just a cleaner or some sort of contact enhancer. If I can figure out what it was, I'll let you know...
http://www.escape-city.com/viewtopic.php?f=8&t=10&st=0&sk=t&sd=a&hilit=moonroof+switch
There was a member here who said it was the contacts in the switch and there was something he applied that made it work fine. I'm not sure if it was just a cleaner or some sort of contact enhancer. If I can figure out what it was, I'll let you know...