Normal Operation
WARNING: This page is about a different car, the 2005 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.
The multifunction switch sends a reference signal through circuit 8-KA7 (WH/VT) to the windshield wiper motor module (internal); the windshield wiper motor in turn sends battery voltage through circuit 75S-KA7 (YE/VT) to activate the washer pump motor.