All dishwasher detergent dispensers have some sort of spring that opens the detergent door. It is very common for the spring to break on Whirlpool dishwashers with the dispenser door at the bottom right of the dishwasher door. Other springs such as the round type for GE hardly ever break but if they do, the dispenser will not work. So check to see if the spring is broken and if so replace it.
Some dishwashers have a dispenser modular and individual parts cannot be purchased. In this cas,e you will have to replace the whole modular.
On some older Maytag dishwashers it is very common for the hook that sticks through the inner door that the dispenser door locks into will wear out or the spring will break. Look below the dispenser door and see if the hook is worn or if it doesn’t have spring tension.
Dishwasher detergent dispenser assembly. This new dispenser has a mechanical rinse aid indicator. If the original dispenser had a rinse aid sensor with a two wire harness, that is no longer required. The two wire harness is not used and can be tied to the door wiring harness so it is out of the way.
Most dishwasher detergent dispensers on most brand dishwashers today use wax motors. Some use two, one for the detergent and the other for the rinse aid. Overall, wax motors don’t give a lot of trouble so before considering the wax motor; check all mechanical linkages and springs. Wax motors are basically the same but depending on the motor the ohms across the motor varies. GE wax motors are 1200-2800 ohms and a lot of Whirlpool wax motors are 600-1800 ohms. The best thing is to refer to the mini manual provided with the dishwasher. If you don’t have a mini manual, I suggest checking ohms with your meter set to the highest setting and if it reads open replace it. If it doesn’t, assume it is good but the only way to know for sure is to monitor the voltage coming to the motor. If it gets voltage but will not move, the motor is bad. If it doesn’t get voltage the control is bad. Note that unless you check you mini manual you will not know exactly when the control will activate the wax motor. It should be sometime in the main wash cycle. If your dishwasher has a mechanical timer you can turn it slowly while monitoring voltage, at some point you should see voltage at the wax motor. If your dishwasher has an electronic control you may be able to enter it into a service mode to manually activate the wax motor. Refer to the mini manual provided with the dishwasher for instructions on how to do so.
WP8558129 Kitchen Aid Dishwasher Detergent Dispenser. Replaces AP3776575, 8558128, 8269996, 8269121, 8270032, 8270034, 9744542, 9744543, 1066136, AH973797, EA973797, PS973797, 8531825. Click MORE DETAILS link for specific model coverage on this part.