Why is your Whirlpool dishwasher not washing your dishes? Good question. We don't know. But we will, because below you'll find a list of possible causes, with instructions on how to test each one. Work your way down the list and you'll find the reason. When you do, we'll have the part you need ready to order, and instructions on how to install it. Your frustration will melt away and you might just feel satisfaction in saving money on a technician and doing the repair yourself.