Try recycling both battery disconnect switches - the one by the door and the one in the battery compartment. These reset the breakers in the Vansco and I can't remember which controls the step. But when my step quits working, I turn both to "off" for about 45 seconds and then back on, and it resets the circuit and we're fine. Only had to do this twice over the last 4 years, but Mike Glazier, when he still worked at WRV, told me to do it and it's worked both times.
Former Owner, 2006 36MDDS
2010 Arctic Fox 22GK Travel Trailer
2007 Toyota Tundra