Wiper Motor Park Switch

I have variable speed wipers that do not park when you shut them off. The service manual has a section that talks about motor park switch timing and gives instructions on how to manually hook it up to test the park function. In the service diagnosis section, the corrections are to adjust, repair, or replace the park switch but it does not show where the switch is located or how to adjust/repair it if necessary. Where is it, how do you adjust/repair/replace???