Bosch Maxx stops at 8mins

I went to a maxx excel with a time display that was washing continualy so i put it on spin and it was well noisey on the brushes and stopped on 8 mins then went to 1 min then 0 and opened the door as if finished.
So I thought maybe interference from the comm causing the board to act up so i comm sticked the motor which was very rough even though the brushes were fine and ran it again.
When it got to 8 mins it stepped up the spin and I thought I’ve cracked it but it dropped down again and went from 5 mins to 1min to 0.???
I meggered the heater motor checed pump, pressure switch even the valves but all seemed fine.
No error codes displayed so I,m stuck has anyone seen this b4 or know what it is??
Thanks ….