The step is fixed and working properly! Huge thanks to Joel Ashley and Ed Buker for helping me understand how to use the multi-meter, and about continuity, resistance, current, and voltage.
As it turned out, there are two switches that operate the door. I replaced one, and hooked it up wrong (before I learned how to use the meter) and all the time ignored the other one. It was bad too. I suspect the second switch acts as a back up in case of failure of the other one. Apparently, one of the two went bad a long time ago, and the second switch kept the door operating until a wire broke when I was in New Orleans. I have installed both new switches properly (I tested each of them independent of the other) and they both operate the door. The "step out" light works on the dash, and the step retracts when the ignition key is turned on regardless of the power toggle switch being on or off.
Woo Hoo!!
Thanks so much to all.
Stan
