To isolate the MOT failure, try swapping the MOT card with another MOT card. If the failure moves, then the problem is in the card. If the failure does not move, the MOT card is not your problem.
If the MOT card is not the issue, then your problem is either the motor, the encoder, or wiring/connection. Make sure all connectors are well seated, and that any wire/pin connections are not loose.
While you are able to read the encoder counts, it's possible that the machine is not zeroing correctly...causing the encoder counts to be off. While in the admin panel, you should be able to initialize the MOT boards and keep an eye on the encoder results.
Finally, on that 5.6v issue...check the fuses/circuit breakers.
Cheers, ..rob
reply »