If the convection (hot) side of the appliance works, but not the microwave, the chances are either the safety interlock door switches have failed to operate correctly, causing the safety monitor fuse to blow, or the manetron (the thing that makes microwaves) has died, or if the unit is of chineese manufacture the 4000v fuse has failed due to normal operating stress. further advice is available by contacting me via microwave-repairs.co.uk
kindest regards
patrick
August 2012
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