(“In situ” is Latin for “not having to take the whole damn thing apart to get at the stuff you want to test.”)
Anyway, I don’t know if this falls under “Hindsight is 20/20”, or “Experience is the Best Teacher”, but after all the hoo-haa I went through to tear down the motor and test the sensors, first on the board, then out of the board using the test rig David O’Brien set up, I suddenly realized that when the bike was all together I had everything I needed to test it out- power, the right loads, everything. Cue Homer Simpson.
Simply by doing the same thing Rob suggested, I could see if they were working. Apply power across the sensor power inputs, measure from the ground to each sensor and see if we get voltage. Here’s a little video showing how it’s done.
My conclusion after testing was that, with a new, working controller, two of the sensors weren’t turning fully off, which would account for the new behavior of the motor- spinning like it was fighting against itself- only starting after urging, then spinning slowly, then powering off after a few seconds (presumably a thermal cutoff on the controller).
Stay tuned, new sensors on order!