retractable step at sliding side door

[Sawman1]

Good morning, I am having trouble with the retractable step at the sliding cargo door. It started with warning alarm sounding with door open, if I lift the step up with my foot the alarm would go off. (that no longer works). Then the the door worked erratically, it opened all the time, but didn't shut always having to open and shut multiple times to activate step to shut.(alarm always activated upon step opening). Now the step no longer works at all. My guess is there are sensors showing whether the door is shut or open. Any ideas if that is correct and where they might be? 2015 sprinter 2500