Directions for testing a washer's selector switch.
Before you begin to test your washer's selector switch, make sure you disconnect the appliance's power supply. The easiest way to do this is to unplug the unit from the wall. Alternatively, you could trip the appropriate switch in the circuit breaker panel, or you could remove the appropriate fuse from your home's fuse box.
A switch is a mechanism that can make, break, or change the connections in a given electric circuit. Washing machine selector switches determine which cycle is to be used. Many selector switches can be as much as six or even eight inches long. Most are black in color and all have metal prongs, called terminals, extending out from the body of the switch.
Remove the cycle selector switch from unit. It will most likely be secured to the unit's frame with a few screws. The terminals extending from the body of the switch are grouped in pairs of two, one group of terminals for each button. Each group must have its wires removed for testing. Carefuly remove the wiring harness leads from the first pair of terminals of the switch. Do not pull on the wire itself. Needle nose pliers may be needed to remove the wire from the terminal. Replace the wires to the terminals before you move on to the next pair of terminals.
Use your ohmmeter to test your switch for continuity. Set your ohmmeter to measure resistance at a scale of Rx1. Touch the metal tips of the test leads together and zero your ohmmeter by adjusting the thumbwheel in the front of the meter until the needle reads '0' on the scale.
You are going to test one button at a time. Push in on the button of the switch terminals that you are testing. Touch an ohmmeter probe to each terminal. The ohmmeter reading should change from infinity to zero ohms. Keep each probe in contact with its terminal and press in on a different button, releasing the first button. The ohmmeter reading should go back to infinity. Replace the wires to the terminal and repeat these steps for each pair of terminals of the selector switch.
Any readings that differ from the ones presented here are indicative of a defective cycle selector switch that will need to be replaced.