Indesit IWE7145S Stops in cycle, no error code.

Had a look at my sons Indesit IWE7145S machine after he reported it filling but having no movement of the drum.
His wife uses the “quick wash” 15 minute cycle mostly and it was on this program the fault happened.
Opened up the machine and noted black dust and, on checking the brushes, saw they were only just making contact with the commutator if at all.
Ordered and replaced the brushes, and as the machine was filling on the said program, the drum began agitating.
So far so good.
After about 3 minutes of the program and with the drum filled, the drum stopped moving and just sat there.
There’s no error code to indicate either heater or PT100 failure.
Any ideas?
Cheers.