Is my Simpson Eziset 550 washing machine controller defective?

My Simpson Eziset 550 washing machine stops after washing without doing rinse and spin. The settings I use are Normal wash, Medium water level, Warm water, no economy setting. If I then turn the power off and set the dial to "Rinse and Spin" then turn the power back on and press the "start/pause" button it completes the cycle. Does this mean the electronic controller is defective and is there anything i should check before replacing the quite expensive controller?