Hi Richard, replacing a fuse is no answer, fuses are there to blow in case of distress, find the cause first. As I am not familiar with this model, I suspect it is non UK then its hard to say for certain, most likely, as neither fans nor m/w are running it is a control panel fault, or a control failure somewhere switching the mains to the required circuit. As you are messing about in an area that generates 4000volts at leathal current, call an engineer.
kindest regards
patrick, August 2009