Jenn-air microwave--loud hum; blown fuse...
over-the-oven jenn air microwave that we have had for about 11 years, today just hummed for a second and popped the breaker a few seconds after starting a cook cycle.
removed the unit for troubleshooting...
1. If the HV diode is removed from ground, the unit runs, no hum, no heating. (if left in place, the microwave hums the moment i try to run a cycle, blowing the fuse)
2. the HV capacitor has 30 ohms of resistance in both directions. from what i've seen online, the capacitor should be in the range of M ohms resistance, not 30 ohms.
3. the filament of the magnetron tube shows continuity and no short to ground.
the cost of the capacitor is $66. the diode, while seemingly OK when tested with a 9v battery, is so cheap, i'd order one if i order the capacitor.
I have TWO questions:
1. does it make sense that the hum/short goes away if i remove a (what i think is a good) HV diode, and get no heating from the magnetron?
2.if the capacitor IS defective, does it make sense that removing the HV diode, stops the short?
logically, to me, it doesn't make sense that if the cap is bad, that taking the diode out of the circuit would stop the hum/short.