What happens when you start the motorhome? They should retract if the RV is running and the door is closed, no matter whether the "step switch" is on or off. The step operates on the chassis battery, not the coach battery.
If the coach starts and the steps don't retract I would think it has to be the wiring harness connecting the motor for the steps. I'm not sure, but I think the light goes out when setting the "store/use" switch to "store", so I believe the light works from the coach battery.
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