Microwave oven keeps blowing fuses
Solution: Check the door switch as described above. The capacitor or diode may be bad. Discharge the capacitor as described earlier in the article. Test the capacitor by removing the leads and setting the VOM to RX100. Probe the terminals. The reading should start in the low ohms and increase toward infinity. Reverse the probes and re-test. The reading should do the same thing. If not, it's bad. To test the diode, disconnect the diode from both the appliance and the capacitor. With the VOM set to RX100, probe the wires. Then reverse the probes and read again. You should get infinity for one reading and low ohms for the other reading. If not, replace. Another cause could be a faulty magnetron, but due to the sensitivity of that piece, it's best left to a professional.