There is a good possibility of a motor relay being located in the top control console. Test it first and replace if defective. There are also other parts that could be defective like the door switch for example that will prevent the unit from starting if defective. Always test parts before replacing to prevent unnecessary expense.
We are experiencing the same problem with our Whirlpool Cabrio WED6400SW1. I am concerned on how much money I am going to fork out tomorrow when the service man comes.