Odds are you have a Kwikee step. WHY you won't respond with what Brand step is why you cannot get help.
1. If Kwikee, the control modules NEVER go bad. So, if in 5 years you have had 2 modules replaced, you or a Service center was throwing parts at a problem that never got fixed
2. MOTORS on Kwikee DO go bad, even in less than a year. The symptom is intermittent operation. The motor has a dead spot in the Armature. Kwikee Step motor reliability has dropped in the past 10 years ever since LCI purchased Kwikee.
3. To determine if you have a intermittent step motor is simple. Start the engine, IF the step functions you cannot test for a bad motor. IF the step fails to function, Open and close the entry door and look at the underside amber step light. IF THE STEP LIGHT GOES ON AND OFF WHEN OPENING AND CLOSING THE DOOR, THE WIRING IS CORRECT.
4. Now, with step not working open and close the entry door and when opening tap the step motor with a hammer. Not hard enough to dent the casing but hard enough to jar it. IF, after several attempts, the step starts operation, you have a bad motor and need it replaced. Doug