I had the same problem, in my case, dishwasher will fill water, and heats up the water, but it will not start circulation pump (This happens 5 out of 10 times). But, after some time water will be drained and fresh water will be filled, heat the water and this process goes on.
I have checked the motor, drain pumps individually they are working fine. changed turbulance sensor, float sensor and main computer board. But still the problem didn’t go. I am not suspecting the door latch, as the door locks fine, and water coming in and heater is running. So, I am confident door latch is working fine.
The surprising part is, once I reset the computer 123123123 process, then the first iteration goes perfect, nicely clean all dishes and dry them up. so, confused what could be wrong here.