I rewired it so that the motors were switched. When I did that, manual control worked perfectly for motor 2 (by calling it motor 1 in the software), but not motor 1 would only move in a narrow range.
I switched the wiring back and it went back to the original behavior – motor 1 worked as design and motor 2 no longer worked.
I think that rules out the wiring and the motors and puts the driver board in question. I’ve got a multi-meter I can use to do more testing, if you think it would help.
