Sunroof Problem

I'm about to purchase a 97 PA Sedan with a power sunroof that opens and vents just fine, but has trouble closing. Closing from vent position is ok, but current owner says nothing happens when switch is activated to close from full or mostly open position. Last couple of times (before he stopped using it altogether) he disconnected and reconnected the battery which made it work again to close. Same problem again next time it was opened.

Any ideas? I've heard that some cars have separate relays for open and close function. Anyone with experience in this area? I love the car and would really like a functional sunroof for the summer. I've never owed a car with one before and my head needs a tan! :rolleyes: