Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Remove the diverter valve motor from the body

Observation:

Press the spindle of the diverter valve in with a screwdriver.
It should move in freely by approximately 7mm.
Release the spindle and it should spring back freely by approximately 7mm.
Does the diverter valve spindle behave as described above?