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A float switch on a dishwasher is designed for one thing, to stop the water flow from the dishwashers water valve. Dishwasher repair is not hard with the proper knowledge, this site is dedicated to the DIY Appliance repair homeowner, if you require further assistance after reading this article our DIY Repair forum is only a click away.
The float switch on most modern dishwashers is located in the front corner of the dishwasher, this mushroom looking, usually plastic dome shaped is what activates the actual float switch. Start by lifting up on the plastic piece and then eaze down, do you hear the switch activate? You should hear a slight click if the float is in the track to activate the switch.
To access the dishwasher float switch regardless of the make or model, 99% of dishwashers are accessed from behind the toe kick panel. Most manufactures for instance Whirlpool, Maytag, GE, Kitchenaid, Kenmore and even some of the high end dishwasher like Bosch, Dacor and even Viking are accessed for the most part by removing the access panel on the bottom of the dishwasher.
With the toe panel removed the float switch may be exposed or could be behind a small plastic housing, usually shaped for the small switch to fit in. If the switch is in cased in a plastic housing, there will be a small plastic tab to pull out on to reveal the actually float switch.
When the timer or main control call for water, power is sent through the float switch wires, when the dishwasher has filled up raising the plastic mushroom looking piece high enough, the switch will stop power from getting to the water valve. That is the idea behind the switch, to further test this switch with a volt meter and other components on the dishwasher, come speak to a trained technician in our repair forum.