Lever microswitch, the type used for door and position sensing in appliances
Generic photo: Raimond Spekking · CC BY-SA 4.0

How to test a selector or rotary switch (temperature, cycle, fan speed)

Selector switches route power to different circuits in each position. Like a timer, you need the switch chart from the wiring diagram to know which terminals should connect in each position.

Single source ~20 min easyBrands: All

Before you start

  • Unplug the appliance or turn off the breaker before opening panels or disconnecting parts
  • Take a photo of the wiring before removing any wire
  • Resistance and continuity tests are done with power OFF and the part isolated

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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