Bosch Dishwasher making noise: Common Causes & How to Fix

Repair Instructions:

The wash impeller is like a small plastic fan that pushes water through the spray arms to clean your dishes. When some of its blades break, your Bosch dishwasher can get noisy. If the impeller is damaged, warped, or bent, it might scrape against the pump housing, causing noise and potential issues. If the part is damaged it will need to be replaced. Some Bosch dishwasher models allow you to change the wash impeller on its own, without having to replace the whole pump and motor assembly.

How to Replace Bosch Dishwasher Wash Impeller

1. Unplug Bosch dishwasher and shut off water supply. Disconnect power cord and turn off water inlet valve.

2. Remove lower access panel or toe kick plate. Find mounting screws/clips and detach the bottom front panel.

3. Locate circulation pump and disconnect hoses. Squeeze hose clamps and slip hoses off pump water ports.

4. Remove circulation pump from Bosch dishwasher. Use a nut driver or wrench to detach mounting screws securing the pump assembly.

5. Take out impeller from inside pump body. The impeller slides straight out of the center opening after removing mounting hardware.

6. Clean inside of pump housing. Wipe away debris from the area where the new impeller will mount in the center opening.

7. Insert new impeller into pump body. Align tabs and firmly press impeller fully into center opening until flush.

8. Reattach circulation pump and hoses. Replace any gaskets, tighten mounting bolts and reconnect hoses to ports.

9. Replace access panel and test. Reconnect water and power, then run a test empty cycle to check operation.

10. Inspect wash performance during operation. Run full cycles to make sure you have adequate water coverage from new wash impeller.

Repair Instructions:

Parts of the pump and motor assembly, like the motor bearings, drain impeller, or wash impeller, might be damaged. In many cases, you have the option to replace these individual parts. If you prefer not to take apart the pump for these replacements or if the parts are not sold separately, you will have to replace the whole assembly.

How to Replace Bosch Dishwasher Pump and Motor Assembly

1. Disconnect power to Bosch dishwasher at circuit breaker. Shut off for safety before servicing.

2. Remove lower kick panel and drain hose from pump. Detach hose clamp to separate parts.

3. Note position of wires on motor terminals for reconnecting later. Take clear photos if needed.

4. Disconnect wires from existing pump motor one at a time. Carefully remove without damaging.

5. Remove mounting screws securing pump body to Bosch dishwasher tub. Lift out entire assembly.

6. Clean area where new pump will mount. Remove debris from mounting surface.

7. Mount replacement pump body using screws removed earlier. Align mounting holes properly.

8. Reconnect wires individually matching positions noted earlier. Refer to photos as needed.

9. Reattach drain hose to new pump with clamp. Make sure you have a tight secure connection.

10. Replace lower panel and reconnect power. Run test cycle to check new pump operation.

11. Inspect installation and make adjustments as needed.

Repair Instructions:

Check drain pump, make sure it's clear of any debris or clogs. If the pump is still making unusual noises during operation the pump will need to be replaced.

How to Replace Bosch Dishwasher Drain Pump

1. Unplug Bosch dishwasher and disconnect hoses. Remove the power cord from the outlet and disconnect the drain and inlet water hoses from theold pump.

2. Remove kick panel. Look for mounting screws, tabs or clips along the bottom front of the appliance. Use a screwdriver to release any fasteners holding the kick panel in place.

3. Locate and remove old pump. The pump is usually located near the bottom center or bottom right corner inside the Bosch dishwasher. Use a wrench to remove any mounting bolts. Carefully pull out the old pump.

4. Clean area around new pump site. Wipe away any debris or standing water near where the new pump will mount.

5. Install new drain pump. Set the new pump in place and secure it with the mounting bolts. Hand-tighten bolts securely.

6. Reconnect hoses to pump. Push drain and inlet hoses securely over barbs at pump. Make sure the hose clamps are tight.

7. Replace kick panel. Align panel and secure with any screws or fasteners removed earlier.

8. Plug in and test Bosch dishwasher. Reconnect power cord and run a short cycle to check for leaks and ensure new pump is functioning properly.

Repair Instructions:

The circulation pump has a motor with bearings inside. These bearings wear out over time. When they fail, they make a loud humming noise. If the motor bearings are bad, the whole circulation pump must be replaced.

How to Replace Bosch Dishwasher Circulation Pump

1. Shut off water supply and unplug Bosch dishwasher. Turn off the water valve and disconnect the power cord from the outlet.

2. Remove toe panel or kick panel. Find mounting screws/clips and remove the bottom front panel.

3. Locate circulation pump. It's usually located at the bottom of the Bosch dishwasher, towards the front near the toe panel area.

4. Disconnect hoses from pump. Gently squeeze hose clamps and detach hoses from water inlet and outlet ports on the pump.

5. Remove mounting screws. Use a nut driver or socket wrench to remove screws or bolts securing the pump assembly in place.

6. Detach electrical connection. Disconnect the wiring harness plug from the back of the pump motor.

7. Remove old pump. Pull out the circulation pump from the Bosch dishwasher.

8. Install new pump. Set the replacement pump into position and hand-tighten mounting screws.

9. Reattach hoses and wires. Secure water inlet and outlet hoses to ports with clamps. Plug wiring harness into new pump.

10. Replace front panel and test. Reinstall lower panel and run a cycle to check for leaks on hose connections.

Repair Instructions:

The drain impeller pushes water out the hose to the garbage disposal or drain. If the impeller is cracked or broken or making noises, it needs to be replaced.

How to Replace Bosch Dishwasher Drain Impeller

1. Unplug Bosch dishwasher and shut off water supply. Disconnect the power cord and turn off the water inlet valve.

2. Remove lower access panel or toe kick plate. Find and remove mounting screws or clips holding the panel in place.

3. Locate the drain impeller under the Bosch dishwasher. It is usually housed at the bottom of the tub interior near the drain pump assembly.

4. Disconnect drain pump hoses. Gently squeeze hose clamps and slip hoses off of drain pump ports.

5. Remove drain pump mounting screws. Use a nut driver or wrench to detach the drain pump from its mounting location.

6. Take out drain impeller from underside of pump. The impeller slides straight out of the center of the drain pump body.

7. Clean inside of pump housing thoroughly. Wipe away debris from area where new impeller will mount.

8. Slide new drain impeller into pump body. Align tabs and press fully into center opening until flush.

9. Reattach drain pump and hoses. Replace any gaskets, tighten mounting bolts and push hoses onto ports.

10. Reinstall access panel and test operation. Reconnect water and power to run a test empty cycle.

Repair Instructions:

The circulation pump has a motor with bearings inside. These bearings wear out over time. When they fail, they make a loud humming noise. If the motor bearings are bad, the whole circulation pump must be replaced.

How to Replace Bosch Dishwasher Circulation and Drain Pump Motor

1. Unplug and disconnect water. Turn off power at breaker and water supply before starting repairs.

2. Remove access panel. Find screws or clips holding bottom panel and carefully detach it.

3. Locate circulation or drain pump. Pumps are usually mounted under the Bosch dishwasher tub.

4. Disconnect hoses from pump. Gently squeeze clamps and detach hoses from water inlet/outlet ports.

5. Remove mounting bolts. Use a wrench or socket to detach pump assembly from Bosch dishwasher wall.

6. Detach old motor wires. Disconnect electrical plug joining motor to Bosch dishwasher wiring harness.

7. Pull motor from pump body. Remove mounting bolts fully to detach old motor.

8. Install new motor. Set replacement motor into pump body slots and hand-tighten mounting bolts.

9. Reattach wires and hoses. Push plugs fully onto motor and slide clamps over reattached hoses.

10. Reinstall access panel and test cycle. Reconnect power and water supply, then run empty cycle to check new motor.

Repair Instructions:

A broken or worn spray arm can cause noises in the unit. If you notice noises coming from the spray arm or any damage you will need to replace that spray arm.

How to Replace Bosch Dishwasher Lower Wash Arm

1. Unplug Bosch dishwasher and shut off water supply. Disconnect power cord and turn off inlet valve before starting repairs.

2. Remove lower access panel. Find mounting screws or clips and carefully detach bottom front panel.

3. Locate lower wash arm inside tub. It is mounted towards the bottom center or rear of the Bosch dishwasher tub interior.

4. Disconnect wash arm from fitting. Gently twist arm connector and pull away from socket in tub wall.

5. Remove obstructing debris if necessary. Clean any food or mineral buildup from wash arm spray holes.

6. Inspect fitting socket for damage. Check that socket is clear and not cracked before reinstalling wash arm.

7. Attach new or cleaned wash arm onto socket. Push arm end firmly back into the tub wall fitting until it clicks into place.

8. Replace access panel and run test cycle. Reconnect power and water lines then run empty cycle to check spray pattern.

9. Check wash coverage after a full load. Run soiled dishes to make sure the arm sprays sufficiently during cycle.

Repair Instructions:

The water inlet valve in your Bosch dishwasher lets water into the unit. When it's brand new, it operates quietly. As it ages, the diaphragm inside the valve can deteriorate and change shape. This change interacts with the water rushing in, leading to noisy disturbances like vibrations, buzzing, or squealing. If you notice that your Bosch dishwasher gets loud specifically during the phase when it's filling up with water, you will need to replace the water valve.

How to Replace Bosch Dishwasher Water Inlet Valve:

1. Safety Precautions:

   • Begin by ensuring the Bosch dishwasher is disconnected from the power source and water supply to guarantee your safety during the replacement process.

2. Access the Water Inlet Valve:

   • Locate the water inlet valve, typically found at the bottom of the Bosch dishwasher, behind the lower access panel.

3. Gather Necessary Tools and Replacement Parts:

   • Ensure you have the required tools, such as pliers and a screwdriver, and acquire a compatible replacement water inlet valve.

4. Disconnect Water Supply:

   • Turn off the Bosch dishwasher's water supply, which is usually located under the sink. Disconnect the water supply hose from the inlet valve.

5. Remove the Access Panel:

   • Use the screwdriver to remove the lower access panel of the Bosch dishwasher, providing access to the inlet valve.

6. Disconnect Wiring and Hoses:

   • Carefully disconnect the wiring and hoses attached to the old water inlet valve. Take note of their positions for reconnection.

7. Remove the Old Valve:

   • Gently detach the old water inlet valve from its mounting point, often secured with screws or mounting brackets.

8. Prepare the New Water Inlet Valve:

   • Unpack the replacement water inlet valve and inspect it for any defects. Ensure it is clean and free from any packaging materials.

9. Install the New Valve:

   • Carefully position the new water inlet valve in the same location as the old one, securing it with the original screws or mounting brackets.

10. Reconnect Wiring and Hoses:

    • Reconnect the wiring and hoses to the new water inlet valve, ensuring they are properly and securely attached.

11. Reattach the Access Panel:

    • Place the lower access panel back onto the Bosch dishwasher and secure it with the screws you removed earlier.

12. Turn On Water Supply:

    • Reconnect the water supply hose and turn on the Bosch dishwasher's water supply.

13. Plug In and Test:

    • Reconnect the Bosch dishwasher to the power source and run a test cycle to ensure the new water inlet valve functions correctly and no leaks are present.

14. Final Check:

    • Inspect the new water inlet valve and its connections to ensure they are properly installed, preventing any water supply issues during Bosch dishwasher operation.

Repair Instructions:

When you hear unusual noises in your Bosch dishwasher, especially during the wash cycle, it's possible you have a worn-out circulation pump motor. This motor consists of an impeller and bearings that can deteriorate as time goes by. When the motor's bearings wear out, they can create a continuous droning sound. If the impeller is broken or damaged, it may lead to a grinding noise. You will need to replace the circulation pump motor to correct the noise issue.

How to Replace Bosch Dishwasher Circulation Pump Motor:

1. Safety Precautions:

   • Start by ensuring the Bosch dishwasher is disconnected from the power source to guarantee your safety during the replacement process.

2. Access the Circulation Pump Motor:

   • Locate the circulation pump motor, typically found at the base of the Bosch dishwasher, inside the tub.

3. Gather Necessary Tools and Replacement Parts:

   • Ensure you have the required tools, including a screwdriver and pliers, and acquire a compatible replacement circulation pump motor.

4. Remove the Lower Dish Rack:

   • To access the circulation pump motor, slide out the lower dish rack from the Bosch dishwasher.

5. Disconnect Wiring:

   • Carefully disconnect the wiring attached to the old circulation pump motor. Take note of the wiring connections for reconnection.

6. Detach the Pump Housing:

   • Using a screwdriver, remove any screws or clips that secure the pump housing to the Bosch dishwasher.

7. Disconnect Hoses:

   • If there are hoses connected to the pump motor, disconnect them, ensuring you know where each hose connects.

8. Remove the Old Pump Motor:

   • Gently detach the old circulation pump motor from its mounting point, taking care not to damage any surrounding components.

9. Prepare the New Pump Motor:

   • Unpack the replacement circulation pump motor and inspect it for any defects. Ensure it is clean and free from any packaging materials.

10. Install the New Pump Motor:

    • Carefully position the new circulation pump motor in the same location as the old one, securing it with the original mounting hardware.

11. Reconnect Hoses:

    • Reconnect any hoses that were disconnected, ensuring they are properly and securely attached.

12. Reattach the Pump Housing:

    • Secure the pump housing to the Bosch dishwasher with the screws or clips you removed earlier.

13. Reconnect Wiring:

    • Reconnect the wiring to the new circulation pump motor, ensuring they are properly and securely attached.

14. Reassemble the Lower Dish Rack:

    • Slide the lower dish rack back into the Bosch dishwasher, ensuring it is properly aligned and securely in place.

15. Plug In and Test:

    • Reconnect the Bosch dishwasher to the power source and run a test cycle to ensure the new circulation pump motor functions correctly, effectively circulating water for washing.

16. Final Check:

    • Inspect the new circulation pump motor and its connections to ensure they are properly installed, contributing to efficient dishwashing performance.

Repair Instructions:

Bosch Dishwashers usually have multiple wash arms, with one for each rack. Sometimes, if a handle or utensil sticks out through a rack, the wash arm can hit it when it's spinning. Another possibility is that an item in the Bosch dishwasher is too tall and blocking the upper wash arm. It's important to make sure that nothing is getting in the way of both the upper and lower wash arms to make sure your dishes get cleaned properly.