The part(s) or condition(s) listed below for the symptom Dishwasher not cleaning are ordered from most likely to least likely to occur. Check or test each item, starting with the items at the top of the page.
The water inlet valve opens to allow water to enter the dishwasher. If the valve is clogged or defective, the dishwasher won’t get enough water to clean dishes properly. If the water inlet valve is clogged, replace it. Do not attempt to clean the water inlet valve—cleaning the valve could make it more likely to fail.
Improper loading will keep the water from cleaning the dishes. Make sure you are leaving enough space between the dishes.
The water may not be hot enough. The recommended water supply temperature for a dishwasher to clean properly is 120 degrees Fahrenheit (49 degrees Celsius). If your hot water temperature is lower for safety reasons, try using a longer cycle that heats the water.
The center wash arm is attached to a support that is normally attached to the underside of the upper dishrack. Water flows through the support to the arm which circulates the water to the dishes in the upper rack. If the support is damaged or obstructed water may not flow properly. Inspect the support for any damage or obstruction and replace if necessary. In addition, make sure that the support is mating properly with the water supply nozzle.
The center wash arm circulates water to the dishes in the upper rack. If water can’t flow properly through the center wash arm, the dishes in the upper rack won’t be cleaned properly. Over time, food particles can get trapped in the tiny holes in the wash arm. If your dishes are coming out dirty, the wash arm might be clogged. To unclog the center wash arm, remove the wash arm and dislodge any debris from the holes. If the wash arm is extremely clogged, replace it. In addition, make sure that the center wash arm assembly is mating properly with the water supply nozzle.
The lower wash arm circulates water to the dishes in the lower rack. If water can’t flow properly through the lower wash arm, the dishes in the lower rack won’t be cleaned properly. Over time, food particles can get trapped in the tiny holes in the wash arm. If your dishes are coming out dirty, the wash arm might be clogged. To unclog the lower wash arm, remove the wash arm and dislodge any debris from the holes. If the wash arm is extremely clogged, replace it.
The lower wash arm is attached to a support fastened to the sump assembly. Water flows through the support to the arm which circulates the water to the dishes in the lower dishrack. If the support is damaged or obstructed water may not flow properly. Inspect the support for any damage or obstruction and replace if necessary.
A dishwasher's lower wash arm will spray water upwards as it rotates to clean the dishware during the wash and rinse cycles. If the wash arm is clogged with debris or damaged, the water won't be able to jet upwards and the dishware won't be cleaned effectively.
The upper wash arm is attached to a support that provides water to the arm to spray the dishes in the upper dishrack. If the support is damaged or obstructed water may not flow properly. Inspect the support for any damage or obstruction and replace if necessary.
The upper wash arm circulates water to the dishes in the upper rack. If water can’t flow properly through the upper wash arm, the dishes in the upper rack won’t be cleaned properly. Over time, food particles get trapped in the tiny holes in the wash arm. If your dishes are coming out dirty, the wash arm might be clogged. To unclog the upper wash arm, remove the wash arm and dislodge any debris from the holes. If the wash arm is extremely clogged, replace it.
The sump assembly, located at the bottom of the dishwasher tub, contains the pump motor or motors to both circulate and drain the water. There are usually two filters in this assembly to strain food particles: a course filter and a fine filter. If the filters are clogged, the unit will get low water flow and poor washability. To clean filters, remove them from the sump and wash them with soap, warm water, and brush.
If the dishwasher is not cleaning well, the holes in the wash or spray arms may be clogged with debris, not allowing water to spray out or the arm to turn. Most wash arms are removable for cleaning. You can clear out the holes with a paper clip or small brush and run water through the wash arm to help clear out the debris.
Some dishwashers use a heating element to heat the dishwasher during both the washing and drying cycles. If the heating element has failed, the dishwasher may not clean the dishes properly. To determine if the heating element has burned out, use a multimeter to test it for continuity. If the heating element does not have continuity, replace it.
A dishwasher's control board provides power to nearly every electrical component in the dishwasher. A faulty board may be unable to supply power to the water inlet valve, preventing it from opening and allowing the necessary water to fill the tank.
The circulation pump uses a motor and impeller to force water up through the wash arms. If the circulation pump is defective, the dishes won’t be cleaned properly. If the motor isn’t making any noise or is just making a humming sound after the dishwasher has filled, the motor may be burned out. First, ensure that power is getting to the motor. Second, to ensure that the impeller can turn, check the pump housing for debris. If power is getting to the motor and the pump is clear of debris, the motor might need to be replaced. Be aware that the circulation pump may be challenging to replace, although many do-it-yourselfers have been successful with the replacement.
The motor drives an impeller to force water up through the wash arms. If the motor is defective, the pump impeller is broken, or some part of the pump is clogged, dishes won’t be cleaned properly. Make sure that power is getting to the circulation pump and motor. If power is getting to the pump and motor assembly but it still won’t run, replace the pump and motor assembly.
The wash impeller is a small plastic blade that forces water up through the wash arms. If the impeller is broken or is missing some of its fins, it might not generate enough pressure to force the water up through the wash arms. On most models, you can replace the wash impeller independently of the pump and motor assembly. Search for your model number to determine if your impeller is replaceable. If the impeller cannot be replaced separately, you will have to replace the entire pump and motor assembly.
A dishwasher's main control board provides power to nearly every electrical component in the dishwasher. A faulty board may be unable to supply power to the water inlet valve, preventing it from opening and allowing the necessary water to fill the tank.
The circulation pump uses a motor and impeller to force water up through the wash arms. If the circulation pump is defective, the dishes won’t be cleaned properly. If the motor isn’t making any noise or is just making a humming sound after the dishwasher has filled, the motor may be burned out. First, ensure that power is getting to the motor. Second, to ensure that the impeller can turn, check the pump housing for debris. If power is getting to the motor and the pump is clear of debris, the motor might need to be replaced. Be aware that the circulation pump may be challenging to replace, although many do-it-yourselfers have been successful with the replacement.
Too much detergent with soft water will cause oversudsing and poor cleaning results. Adjust the amount of detergent being used to the water hardness and the cycle you choose. Always use fresh detergent.
The upper wash arm circulates water to the dishes in the upper rack. If water can’t flow properly through the upper wash arm, the dishes in the upper rack won’t be cleaned properly. Over time, food particles get trapped in the tiny holes in the wash arm. If your dishes are coming out dirty, the wash arm might be clogged. To unclog the upper wash arm, remove the wash arm and dislodge any debris from the holes. If the wash arm is extremely clogged, replace it.
Detergent Dispenser
Drain Pump
A dishwasher's filter assembly usually consists of both a course and a fine filter located in the sump. If one or both of these filters is clogged, you will get low water flow and poor washability. If the filters cannot be cleaned effectively or if they are damaged, they will need to be replaced.
A dishwasher will usually have both a course and a fine screen filter located in the sump. If one or both of these filters is clogged, you will get low water flow and poor washability. If the filters cannot be cleaned effectively or if they are damaged, they will need to be replaced.
Dishwashers will use a strainer located in the sump to catch food particles. If the strainer is clogged, you will get low water flow and poor washability. If the stainer cannot be cleaned effectively or is damaged, it will need to be replaced.