Zanussi aquacycle FW1465W Washing Machine?

Zanussi Aquacycle FW1465W
When the programme is selected and the "Start" button is pressed there is the usual second or two delay then 3 or 4 clicks from the door switch then the "End " button illuminates and the power goes off. (The little light on the door which should come on when "Start" is selected doesn't come on.)

We assumed it was a faulty door switch so have changed it and put in a new switch but the problem remains.

Could it be the electronic circuit board and if so any idea of the cost of one and is it easy to fit yourself?

Does anyone have the answer please?

Thanks