rear wiper goes down before up from park

[btrvalik]

I just replaced my rear wiper motor. I installed the blade so it was horizontal when off. When I the wiper starts it's wipe, it goes down about 2 inches (at the outmost point) and then heads up. Unfortunately this means it has put a few minor scratches in the paint. I've tried pulling the fuse when it is a the bottom of the sweep hope it would reset the park position, but this seems to make not difference. Is this normal behavior? I purchased the motor from a BMW dealer.