The Tech who told you to loosen the bolts and tap the motor must be reading my posts on the forums :) I came up with that, but I don't loosen the bolts.
This is part theory, here is the theory part. Kwikee buys "2nds". the motors are common window riser motors used by either ford or GM or Chrysler depending on your step model but I believe they buy "2nds" the motors often have a "Dead spot" and if the motor stops on the dead spot. ... well it don't work
Taping the thing causes the motor to rotate slightly (the aramature rotates) getting off the dead spot.
How I fixed mine.. twice.. I opened the transmission (DO THIS CAREFULLY and if you do not remove it from RV (I did the 2nd time) Tarp the ground as there is a "Small part" that can easily get lost. Re position the gears a notch or two so the motor does not stop where it used to stop. Works great.