I recently completed a kitchen remodel that took 4 months. The contractor warned me that 50% of the time the dishwasher won't work after sitting around unused. At any rate, it drains and even starts to fill with water but then a hum (i'm assuming the motor) goes on for 8-10 seconds then shuts off. A repairman said it was a bad motor ($500!) Surely there is a way to unfreeze the motor?
I've been reading that on most dishwashers, you can rotate the motor blades and getting it going again. But Bosch conceals the motor in plastic. I've even tried to loosen the pump impeller(?) Still stuck. ANY help will be greatly appreciated. I really don't want to go dishwasher shopping after all of this...

its almost 6 years old...