You can get an idea about the cause by working out the point in the dishwashing cycle where the fault occurs...
If the trip happens as soon as the machine is plugged in and switched on then it may be the powers supply for the logic board.
If you select a cycle and don't hear water entering then it may be the water inlet solenoid
If you hear the water entering but don't hear any water sloshing around then it may be the circulating pump
But my guess as the most proable cause is the heating element
There's another solenoid that opens the detergent hatch but I have no idea if this might be the culprit.
I doubt very much that the drain pump is to blame
Good luck...
Peccavi, September 2009