How to Test a Dishwasher’s Circulation Pump Using a Multimeter

Testing a circulation pump in a dishwasher involves a series of steps to ensure the pump is functioning correctly. This article will guide you through the process using a multimeter. Following these steps will help you diagnose common issues and determine whether the pump needs to be replaced.

Tools Needed

Steps to Test the Circulation Pump

Safety First

Step 1: Unplug the Dishwasher or Turn Off the Circuit Breaker

Ensure safety while working on the appliance by unplugging the dishwasher or turning off the circuit breaker. This simple step will prevent any electrical shock or injury.

Access the Circulation Pump

Step 2: Remove the Lower Spray Arm and Any Covers or Panels

Access the circulation pump by removing the lower spray arm and any covers or panels that protect the pump. This may require a screwdriver. Proceed with caution to avoid damaging any parts.

Visual Inspection

Step 3: Check for Visible Signs of Damage

Inspect the pump and its connections for any visible signs of damage such as cracks or leaks. If you notice any damage, the pump may not function properly and should be replaced.

Test for Continuity

Step 4: Set Your Multimeter to the Continuity Setting or Resistance/Ohms

Set your multimeter to the continuity setting or resistance/ohms. This will help you determine if there is continuity in the pump's windings.

Step 5: Disconnect the Pump’s Electrical Connector

Before testing, disconnect the pump’s electrical connector to isolate the pump from the circuit.

Step 6: Place the Multimeter Probes on the Pump Terminals

Place the multimeter probes on the pump terminals. A reading of near zero ohms indicates continuity, meaning the pump's windings are intact. If the reading is infinite or very high, the pump is likely faulty and needs to be replaced.

Check for Voltage

Step 7: Reconnect the Pump’s Electrical Connector

Reconnect the pump's electrical connector if it was disconnected for the previous step.

Step 8: Set the Multimeter to the AC Voltage Setting

Set your multimeter to the AC voltage setting to measure the voltage across the pump terminals.

Step 9: Turn the Dishwasher On and Run a Wash Cycle

Run a wash cycle that activates the circulation pump to check if the pump is receiving power. You should see a voltage reading consistent with the dishwasher's specifications, usually around 120V in North America. If there is no voltage, the issue may be with the wiring, control board, or timer.

Test the Impeller

Step 10: Check the Impeller for Blockages or Damage

If the pump has continuity and is receiving power but is not working, check the impeller for blockages or damage. Remove any debris that may hinder its movement.

Reassemble

Step 11: Reassemble Any Parts You Removed

Once testing is complete, reassemble the parts you removed and ensure everything is secure. This will prevent any additional damage or issues.

Conclusion

If the pump does not have continuity or does not receive power, it may need to be replaced. If the pump does receive power but is not functioning, the pump itself may be defective. Always refer to the dishwasher's service manual for specific troubleshooting steps related to your model. By following these steps, you can effectively diagnose and resolve issues with your dishwasher's circulation pump.

Additional Resources

For more in-depth information on troubleshooting dishwashers and other household appliances, visit Home Guides. Our guides cover a wide range of topics, from washing machine issues to overall appliance maintenance.