Figured it out, methinks!
It needs a new wire hanrness, or at least new connectors to the microprocessor(tiny ones) The existing ones are in varying conditon and some have "holding bends" only on one side, others are broken off to just a tab, with no real grab on the front and back of what looks like a foil connection to the microprocessor. No wonder it worked for a moment, then when moved it did not. I am not confident about soldering, Like Bobby from Boston, so I am getting a new wire harness.
The connections to the control switch look sketchy as well, so this will be a completely rebuilt machine when done.