My 2000 Buick Century has a wiper issue.My windshield wipers will not go to the park position with the switch off. I push them down and they go right back up to full extension. Is this an issue in the switch or in the motor itself.

Probably the PCB in the motor housing has failed.

It'* neither.....it'* the rotating, two piece arm, that comes off the motor.....the arm has two positions, one for the wipe cycles, and one for the park position......the bracket that holds the motor in place, has a "tab" that sticks up......over time, it becomes bent, and does not engage with the bottom latch of the two piece arm, when commanded to the park position, that'* why the wiper arms stay up.......If I remember right, there was a recall for this, but I am not sure of the models and the years.....

Saw this happen a lot in the winter time, customers would not clear the frozen snow on the wipers, and the motor would attempt to move, and bend the tab....in your case, it just bent it over time....easy fix though....