Problem with the water level control system. Pressure switch giving a negative reading. With the drum completely empty, remove air hose from switch and blow through to ensure that it is clear of any water. If this doesn’t solve the problem, the switch itself may be faulty. It is an integral part of the motor control board, so a replacement assembly would be required.
Thankyou Penguin. The switch was indeed broken and had to get a whole new board, ouch. Was interesting at least to have a play and find out the problem with your help. Cool bananas.