The electric pullout steps on the motorhomes have a simple blade fuse which is usually located near the house battery. The can pop if the button is held down for too long after the step has reached its fully retracted or fully extended position. This is caused by too much current draw trying to drive the step when it has sensed resistance in the motor.
If you step won't go out or in, the first step (no pun intended) is to check the fuse. If the fuse is blown, replace it with the same size (normally 15A blade) and be mindful to relsease the button once the step is in its position.
If the fuse is ok, it may indicate a different problem and will need to be booked in to investigate. You can click the submit a request at the top right corner of your screen to do this.