Thank you for your question and I understand your concern.
I'm not clear in understanding if the wash motor stops running when it reaches the sensing mode or if your indicating the dishwasher is sticking and continuously washing and not advance out of the sensing mode. When it reaches the sensing mode it should continue to wash and heat the water up so that is sees a 2 degree increase if the water temp is greater than 90 degrees or a 4 degree increase if the water temp is less than 90 degrees. If it does not see an increase it will stop running and flash the clean light. With this said, the heating element operation will need to be checked and confirmed during the service cycle test. When you hear the wash motor operate for the third time during the test; the heater should come on. In order to confirm if the heater is coming on the current draw of the heater circuit will have to be tested with a clamp on amp meter.
Note: I do not recommend checking the current draw unless you have experience and feel safe and confident in doing so; otherwise I recommend calling a service technician to diagnose and repair your dishwasher
If you place the dishwasher back into the service diagnostic mode will it complete the service cycle or will it stop somewhere in the service cycle. Press Heated Dry - Normal - Heated Dry - Normal and then let the service cycle complete. After completing the service cycle open and close the door and then start a cycle and see if continues to stop when it reaches the sensing mode.
If you do not feel confident repairing this problem yourself, then you can have it repaired at your home by a Sears technician. Here is a link for the website:
Sears Home Services