could be a faulty switch on the control panel.These are know as energy regulators and when they fail can cause this type of fault.you need to prise the 2 plastic 'L' shaped end caps off the control panel and then this will give you access to screws to release the control panel.undo the grill door and underneath the top edge is 3 more screws.this will then allow you to pull the control panel away from the cooker frame.
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March 2011