How to Troubleshoot a Dishwasher Float Switch

Have you ever opened up your dishwasher after it finished running to discover that the basin is still filled with water? As unsightly as it is, it gives you pause to begin wondering if your favorite coffee mug is getting as sparkling clean as you always believed it was. There can be a number of reasons why your dishwasher isn't draining properly, and the they run from the simple (food caught in the drain grate) to the complex (bad float switch). After you stick your hand in the murky water to discover food is not the problem, it's time to learn how to troubleshoot your dishwasher's float switch.

Instructions

Difficulty: Moderately Challenging

Things You’ll Need:

• Screwdriver
• Flashlight
• Multi-Tester
• Needlenose pliers
• Bucket

1. Because your dishwasher runs by electricity and it is filled with water, be sure to turn OFF the power supply to the machine. You can do this by locating the circuit breaker in your electrical panel and toggling it off.
2. With the power off, remove the top and bottom dish racks and use the small bucket to begin removing the water. Get as much out as you can.
3. With all of the water out, look on the floor of the dishwasher to locate the float assembly. In many dishwashers it is located in the rear of the compartment, but keep in mind it can really be anywhere on the floor of the compartment. It may be concealed by a plastic cover. When you find it, remove the cover. It is usually secured to the floor of the machine with a screw or it may just snap into place depending on the model.
4. Once you see the float assembly, lift the float and let it drop. It should move easily and unrestricted. If it doesn't, look for debris that may be affecting its movement.
5. Remove the float. The float usually snaps into place, so just unsnap the float and pull it out. If it doesn't come out easily, it is probably securely connected to the float switch. Your next step will be to test the float switch to make sure it is working properly.
6. On the front of the dishwasher, at the bottom, remove the kick plate. It is usually held by two screws. With your handy flashlight, locate the float switch. It will be directly underneath the float, so keep in mind where the float was located in the interior compartment and you should find the switch easily.
7. On the float switch, you will see that there are two wires attached to it. These wires are connected with slip-on connectors.
   
   **Be sure the power is OFF before working on the switch. Go double check that the breaker is still off!
   
   ** Use your needlenose pliers to pull the wires off of the terminals. Pull the connectors off by grasping the connector and pulling, NOT by pulling on the wires. You may want to label these wires, or keep notes about what you are doing to ensure that the right wire gets connected to the right terminal when you put everything back together.
8. Grab your multi-tester and set the tester to read Ohms. The setting is usually X1 or RX1. Touch one probe to one terminal and the other probe to the other terminal on the switch. Check the reading. It will either display a reading of zero or infinity.
9. Keep your probes touching the terminals and press the button on the float switch. Depending on what your initial reading was, when you press the switch's button you should get the opposite reading. So, if your initial reading was zero, then you should get an infinity reading with the button pressed, and vice versa.
10. If you get the right readings, then you know your float switch is working. Reassemble the machine and run an empty load to see if the water works its way out. If you still have water in the basin after the empty cycle, then you may have a clog somewhere in your pipes.
11. If you don't get the proper readings, then you will have to replace the float switch.