Talked to Thor last week and on Monday new steps arrived. The Thor tech asked one question, does the light come on? My light comes on but the steps did not operate at all. That must be the key to Thor that there is power to the step and there is a problem with the step mod located on the steps.
I could operate my steps by reversing the poparity between the yellow and red wires going to the step motor. I am going to remove the step mod on the new steps to see if that fixes the problem.
In your case I would watch the step operate from under the coach, there may be something restricting the steps, I understand that the steps stop based on current flow, a restriction would cause the steps to stop before closing or opening completely.
I plan to work on mine in a couple days and will keep you posted.