Asko W90 (aka 10504) only spins

We have an Asko 10504 (aka WM90) washing machine.

When it last ran, it was set to run on a normal wash cycle. When we returned to it, it had stopped. However the door would not release. On opening with the manual release, the drum was still filled with water. I tried to restart the wash; in ALL active positions, the drum spins (at spin speed), the programme control knob drives clockwise until an end of wash position is reached and then it stops. In wash 9 (position to interrupt programme), the machine should just pump out, without any drum movement; instead, the drum spins, and no water is pumped out.

Further checks:
The pump is clear of debris; it runs if powered directly. If the main motor is disconnected, the pump runs in wash 9 (and the timer advances to stop after a minute).
The main motor circuits show resistances of 2, 3 and 15 ohms (field, armature and tacho), with no cross-link.
The heater is not open circuit and there is no earth leak (here or elsewhere). The pressure switch clicks on testing, the supply tube is clear.
There are no signs of burning on the timer PCB.

What is the likely cause of the problem? Faulty timer, main motor or something else? Can they be checked and replacements obtained?

Thanks for your help in advance