David
My Cannon Chichester did this
It was due to the brass connectors inside the microswitch being bent and permanently touching
The switch sits on the shaft attached to the oven knob. You have to strip the panels to expose the switch. It is quite a simple switch with a front and back plastic casing that comes apart and inside are two brass strips that touch when the knob turns, A concentric plastic washer pushes them together as it turns. They become unseated in the plastic case and just requirewd rearranging. Saved myself a cannon call out fee.
GaryC
February 2007
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