Maxima Power Window Timing

Does anyone know how to adjust the "timing" on a Maxima power window?
When I push the auto-up button, the window goes all the way up, and
then comes back down about 3 inches. When this happened in the past,
I took it to the dealer who charged me $50 to adjust the "timing" of
the window. I can't imagine this is too hard once you get the door
panel off. Thanks