Look on the screen door.. There is a magnet. likely near the bottom on the Jam side, it will most likely be a small black retangular thing.
Using a magnetic pick up tool place the magnet where that black plastic thign will be when the door is closed. WITH the switch OFF... This SHOULD retract the steps.
Now turn off.
IF the disconnect switch does not work. or even if it does. I recommend that you LIFT the wire(s) off the NEGATIVE most battery terminal.. IF more than one wire tie them together so you don't miss any come spring.