Here are some operating checks you can make if the dishwasher does not work:
Step 1: Check to make sure it's receiving power. If the unit plugs into a wall outlet, check the cord, the plug, and the outlet to make sure they're functioning properly. Also check the switch that controls the outlet to make sure it's turned on. Most built-in dishwashers are wired directly into a circuit. Check the main entrance panel for a blown fuse or tripped circuit breaker, and restore the circuit. If your home is an older one, the dishwasher may be wired to a separate entrance panel; look for a blown fuse or breaker at this panel, and restore the circuit.
Step 2: If the circuit is receiving power, and the wall outlet is controlled by a switch, the switch may be faulty. Test the switch with a voltage tester. Take off the switch cover plate and place one probe of the tester on one terminal and the other probe on the other terminal. If the tester bulb lights, the switch is functioning. If it doesn't light, the switch is faulty. Replace the switch with a new one of the same type.
Step 3: Make sure the door is tightly closed and latched. The dishwasher will not operate until the latch is properly engaged. To check the latch, close and latch the door, holding the latch tightly in place. Then, still pressing the latch closed, turn the control knob to the ON position. If the dishwasher works, the latch is faulty and should be cleaned, tightened, or replaced.
Step 4: Make sure the water is turned on and the water temperature is high enough. A breakdown in the water heater could stop flow of water to the dishwasher. Test the hot water in the kitchen sink or bathroom. If you can draw hot water, the water heater may not be at fault.
Step 5: Make sure the controls on the control panel are properly set. The newer push-button controls can be very sensitive; make sure the buttons are firmly pressed into position.
If you've gone through these five checks without finding the solution, it's time to dig deeper into the dishwasher.