The main wash motor runs and both upper and lower wash arms are operating normally, water is heating to around 145 degrees. I let the timer run down after the detergent dispensed and the washer ran its 3 short on off cycles. The washer was idle for almost 40 min then drained and refilled and began the rinse cycle and drained normally at the end of the completed wash cycle. Everything appears normal except the wash cycle. The timer now resets to around 108 min so the new control board did correct the long 144 min cycle issue.

The sensor I referred to in my opening post was inside the washer under the filters. Most likely the float not a sensor, but I'm not positive. So to answer your question I have not accessed the sensor you referred to in your last post.

Any suggestions on how to access the sensor?

Is there a diagnostic test I can run to check for sensor faults or other issues with the dishwasher?

Last night I operated the dishwasher in Auto wash (108 min run time) with the same results as before. I then ran it in Regular wash (144 min run time) and it appears to have operated normally, no extended idle periods. However I tested the water temp multiple times and it was not being heated above 120 degrees. In Auto wash the rinse temp is between 140 to 150 degrees. I haven't cleaned the aqua sensor but that is my next step unless you have additional suggestions.