Wiper motor

[PbFut]

Key to testing is to have the motor and swtch housing grounded.
The knowledge that the switch is manipulating ground paths not +voltage helps with understanding the logic of the curciut. The +voltage goes direct to motor. Completing the ground is what energizes the motor and or pump. Be careful, some of the old posts had the motor pins incorrectly identified relative to my situation. I think the ones Doc showed were correct. Once you realize the need for grounds, the testing goes easier.