That switch merely sets a ground. The motor is hot all the time with the key on Yellow wire on motor and pump). The light blue wire sets ground on the high speed circuit, and the black and light blue wires grounded together set ground on the low speed circuit. The dark blue wire sets ground to the washer circuit. There should zero resistance on any of the terminals. You will get continuity between a blade and the metal mounting face as you slide the switch from left to right or push the button in to ground the washer blade.