With these dishwashers it is quite common for the pressure switch (6996821) on the side of the motor to fail, it is 2 changeover switches in one unit, when the machine starts and as it first fills it looks to check that both of the switchs are in the empty position, once full with the pump running then it will be looking to check that they have both switched over to the full position.
I don’t know for certain that that will be your problem but in my experiance may be a good place to start.
Jem