Customer Questions and Answers for Microcomputer by Whirlpool

Chris, You will need to unplug the power cord, remove the upper vent grille then remove the screw holding the control panel to the microwave front panel, and lower the panel. You'll need to check the in line fuse W11707984 and the magnetron thermostat 4393943 for "closed" circuits with a meter and replace which ever part is "open". If either part has an open circuit, power to the control board is eliminated, and the microwave is inoperable/ "dead".