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 float switch (dishwasher overfill and similar)

A float rides up with water and opens or closes a small switch under the tub. It stops overfill or flags a leak. Make sure the float moves freely before blaming the switch.

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

Unlock all 6 steps with expected values

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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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