Diagnose Servis Rainwave bushless motor fault?

So, the tub on my machine is not turning. I've had the motor out and dismantled it. It is an electronically-controlled bushless induction type with what looks like a Hall-effect position sensor, so it is not a problem with bushes. Stuck to the top of the coil is what looks like a thermal fuse. It looks like it has got hot, but I can't say if this is normal or not. Otherwise the motor looks in good condition and the spindle turns freely.

I have located the control circuit, and nothing seems to be amiss. Unfortunately the circuit seems to be directly connected (hard) to the harness.

From this point I don't think I can investigate more without causing undoable damage, so before I plunge in...

How should I proceed to diagnose the fault? How could I work out if the problem is with the motor windings or that thermal fuse (if that is what it is), or with the control board?

Help is very much appreciated.