Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Unclip and remove the diverter motor
(this does not need appliance to be drained down)

Observation:

Check that there is no signs of moisture or corrosion near the spindle.
Push the spindle in, a little more than finger pressure may be required.
Spindle should move in approx 1cm then spring back to position immediately.
Note:
If moisture is present it is advisable
to check the diverter motor.