Uncover the Secret: How to Test Bosch Dishwasher Drain Pump and Keep Your Appliance Running Smoothly

A malfunctioning drain pump can wreak havoc on your Bosch dishwasher, leaving you with a sink full of dirty dishes and frustration. Diagnosing the problem accurately is crucial to ensure an effective repair. This comprehensive guide will walk you through the step-by-step process of testing a Bosch dishwasher drain pump, empowering you with the knowledge to troubleshoot and resolve the issue.

Understanding the Bosch Dishwasher Drain Pump

The drain pump is responsible for expelling wastewater from the dishwasher during the drain cycle. It is typically located at the bottom of the dishwasher, near the sump. When the pump fails, water cannot be pumped out, resulting in standing water and a malfunctioning dishwasher.

Common Symptoms of a Faulty Bosch Dishwasher Drain Pump

• Water not draining from the dishwasher
• Dishwasher not completing the cycle
• Leaking water from the dishwasher
• Unusual noises during the drain cycle
• Error codes related to draining

Safety Precautions

Before testing the drain pump, ensure you take the following safety precautions:

• Unplug the dishwasher from the power outlet.
• Turn off the water supply to the dishwasher.
• Wear safety gloves to protect your hands from sharp edges.

Step-by-Step Testing Procedure

1. Accessing the Drain Pump

1. Open the dishwasher door and remove the lower rack.
2. Locate the drain pump at the bottom of the dishwasher.
3. Remove the access panel or cover to expose the drain pump.

2. Visual Inspection

1. Check for any visible damage to the drain pump, such as cracks or broken wires.
2. Inspect the impeller for any obstructions or debris.
3. Examine the pump housing for any leaks or corrosion.

3. Electrical Continuity Test

1. Use a multimeter set to the ohms setting.
2. Connect one probe to the drain pump terminals and the other probe to the ground terminal.
3. A reading of zero ohms indicates continuity, while an infinite reading indicates an open circuit.

4. Voltage Test

1. Set the multimeter to the volts setting.
2. Connect one probe to the drain pump terminals and the other probe to the neutral terminal.
3. Activate the drain cycle on the dishwasher.
4. A voltage reading of 120 volts indicates that the drain pump is receiving power.

5. Manual Operation Test

1. Disconnect the drain pump from the power supply.
2. Manually rotate the impeller to check for any resistance or binding.
3. The impeller should rotate freely without any obstructions.

Troubleshooting and Repair

1. Faulty Drain Pump

If the electrical continuity test, voltage test, and manual operation test all fail, the drain pump is likely faulty. Replace the drain pump with a new one of the same model.

2. Obstructed Impeller

If the impeller is obstructed, clear the debris or blockage. Ensure the drain hose is not kinked or clogged.

3. Electrical Problem

If the drain pump is receiving power but not operating, check the wiring harness for any loose connections or damaged wires. Replace the wiring harness if necessary.

4. Control Board Issue

In rare cases, a faulty control board can affect the drain pump operation. Contact a qualified technician for control board diagnostics and repair.

Prevention and Maintenance

• Regularly clean the dishwasher filter to prevent debris from entering the drain pump.
• Avoid overloading the dishwasher with dishes.
• Use a dishwasher rinse aid to prevent limescale buildup in the drain pump.
• Run the dishwasher on a hot cycle occasionally to sanitize the drain pump and prevent bacterial growth.

Top Questions Asked

1. How often should I test my Bosch dishwasher drain pump?

It is recommended to test the drain pump every 6-12 months or as needed if you encounter any draining issues.

2. Can I repair the drain pump myself?

While it is possible to replace the drain pump yourself, it is recommended to consult with a qualified technician for electrical repairs or complex troubleshooting.

3. What is the average lifespan of a Bosch dishwasher drain pump?

The average lifespan of a Bosch dishwasher drain pump is typically around 5-7 years, depending on usage and maintenance.