Came out on customer complaint of no wash/tumbling after I helped him with his long drain error code over the phone (button trap was clogged solid). Put into diagnostic mode to the 30 second reversing tumble at wash speed test and the motor would turn a couple times and then do nothing, switch to the next cycle (spin) and would do the same thing after drain out.
I've never seen anything like this that a new motor control board didn't fix so that's what I tried... didn't fix the problem.
Ohmed out the motor and was within specs according to the tech sheet, but it didn't say anything about the tachometer on the back side of the motor shaft. Not sure exactly how it works, but put my meter on it and spun the basket. Read about 50 ohms with no change while the motor was shaft was spinning. Bad tachometer on the motor?