If your Whirlpool dishwasher shuts off suddenly and loses power during the wash cycle, then there is an electrical problem somewhere in the appliance or in the home. This is often apparent because of a tripped circuit breaker. The circuit breaker must be turned off and then back on to reset the breaker and get power to the appliance again. When this happens, you can assume one of a few factors is causing the problem.
Faulty Circuit Breaker
One factor that may cause the breaker to trip, while using the dishwasher, is a faulty breaker. The issue in this instance isn't related to the Whirlpool appliance itself but to the circuit breaker it is wired to. If the breaker itself is faulty, it will need to be replaced. Diagnosis and repair should be left to a qualified electrician.
Excessive Electrical Load
Another non-appliance-related issue is the electrical load. Check the voltage requirements in the literature that came with the dishwasher then look at the voltage supplied by the circuit at the breaker box. If the circuit is overloaded by using the appliance, then it will not support it and will kick off automatically to protect the appliance and the circuitry. You may need to have the washer re-wired to a more powerful circuit for uninterrupted use. Do not attempt to re-wire the dishwasher unless you are experienced in electrical repair.
When one hot wire leading to or from an appliance, such as your dishwasher, touches another hot wire or a neutral wire, then it will cause a short circuit. When the breakers detect a short circuit, the breaker switch will flip off. This problem is likely the result of faulty wiring installed during the appliance hook up or from the outlet where the machine is drawing power to the circuit breaker. It could also be a problem with the dishwasher's power cord or other internal wiring. A short circuit is a potentially serious problem that could lead to appliance damage or fires in the home. An electrician will need to remedy this situation as soon as possible.
If your Whirlpool dishwasher is a plug-in model that is not hard-wired to the home's electrical supply, it may be plugged into a ground fault circuit interrupter or GFCI receptacle. These outlets typically have a reset button on them and are easily identifiable. They are common in bathrooms and kitchen counters or other areas near running water. A GFCI will trip and cut the power to the appliance when it senses an imbalance in electrical current in the hot and neutral wires. This shut down will appear the same as a circuit breaker trip, but the breaker could still be on. Likewise, an improperly working GFCI outlet could result in a breaker tripping as well.