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Here's a diagram without the intermittent module. I am showing this to help you understand how the cam switch works.
You can see on the left side of the switch, when it's put in Lo, power from the red wire is fed directly to the Lo windings of the motor.
The cam switch is in the lower right part of the diagram in the motor.
If the switch is turned off while the wipers are in any position, the cam switch keeps power on them till they hit "park". In the park position, with the wiper switch off, the cam switch grounds out the Lo windings of the wiper motor. This has a braking effect which makes them stop at the bottom of the windshield.