Issue: All motors are no longer working (Frank up/down, target bank up/down, dracula)
Solution: Expected the +12v to be missing for the motors, measured, but 12v was there. Probed the upstream ic's on the power driver board with an osciloscope, and found that the output pins were not pulsing. Probed the input pins for pulses, found that they were not pulsing either. Those pulses are supposed to come from the CPU.
On a hinch i reseated the short ribbon cables between CPU and the Power Driver a couple of times, and motors started working again. Issue resolved.