How to Test the Float Switch in a Dishwasher
The float switch in a dishwasher is crucial for preventing overfilling by stopping the water flow when the water level reaches a certain point. If you suspect that your float switch is faulty, you can test it to determine if it needs to be replaced.
Caution: Please read our safety information before attempting any testing or repairs.
Important Safety Notice: Before testing the float switch, unplug the dishwasher or shut off the power at the fuse box or breaker panel to avoid an electrical shock hazard.
Tools and Materials Needed
- Multimeter or continuity tester
- Screwdriver (Phillips and flat-head)
- Needle-nose pliers
- Safety gloves
Steps to Test the Float Switch
Step 1: Safety First
- Turn Off Power: Ensure that the dishwasher is unplugged or the circuit breaker is turned off to prevent any electrical shock.
- Turn Off Water Supply: If necessary, turn off the water supply to the dishwasher.
Step 2: Access the Float Switch
- Remove the Front Access Panel: The float switch is located beneath the dishwasher tub, accessed through the front lower panel. This panel is usually held in place with two screws either above or below the panel.
- Open the Door: Open the dishwasher door to access the screws holding the lower panel.
- Remove the Screws: Use a screwdriver to remove the screws. You may need to close the door to fully remove the panel.
- Locate the Float Switch: The float switch is located directly beneath the float inside the access area.
Step 3: Disconnect the Wires
- Label the Wires: The switch has two wires connected to it. Use labels or masking tape to mark the wires and their connections for proper reconnection later.
- Remove Connectors: Firmly pull the connectors off of the terminals (do not pull on the wire itself). You may need to use needle-nose pliers to remove the connectors.
- Inspect for Corrosion: Inspect the connectors and terminals for corrosion. If either is corroded, clean or replace them as necessary.
Step 4: Test for Continuity
- Set the Multimeter: Set your multimeter to the ohms setting (Ω) or use a continuity tester.
- Test the Terminals: Touch one probe to each terminal of the float switch.
- Reading: You should get a reading of zero or near zero, indicating continuity.
- No Continuity: If the multimeter shows no continuity (infinite resistance), the float switch is faulty and needs to be replaced.
Steps to Check the Float Mechanism
- Lift and Drop the Float: With the float switch disconnected, lift and drop the float inside the dishwasher tub several times. It should move freely and trigger the switch.
- Listen for Click: You should hear a faint clicking sound as the float activates the switch. This indicates that the switch mechanism is engaging properly.
Step 5: Reassemble the Dishwasher
- Reconnect the Wires: If the float switch passed the continuity test, reconnect the wires to the terminals. Ensure the connections match the labels or markings you made earlier.
- Reattach the Front Access Panel: Replace the lower panel by securing it with screws.
- Close the Door: Ensure everything is properly aligned and close the dishwasher door.
Step 6: Test the Dishwasher
- Restore Power and Water Supply: Turn the power and water supply back on.
- Run a Test Cycle: Run a short test cycle to ensure the dishwasher operates correctly and the float switch functions properly.
Tips and Warnings
- Consult the Manual: Always refer to your dishwasher’s user manual for specific instructions related to your model.
- Use Genuine Parts: If the float switch needs to be replaced, use genuine replacement parts for optimal performance and longevity.
- Check for Leaks: After reassembly, check for any leaks around the float switch area.
- Seek Professional Help: If you are unsure about any step or if the problem persists, consider seeking help from a professional technician.
By following these steps, you can effectively test the float switch in your dishwasher to determine if it needs to be replaced. Regular maintenance and timely repairs will help keep your dishwasher running efficiently and extend its lifespan.
Further Readings