I have a Whirpool GH5184XP microwave / oven hood combo, that blows the circuit breaker only when the cooking function is started. The clock, timer, fans, lights, and all other functions work. When START is pressed, however, the microwave runs for half a second before the circuit breaker trips. It is plugged into a dedicated circuit on the house wiring.

The inverter board has wiring with what seems to be heat damage (like dried-out looking insulation on wires, tiny burned spots, etc.), so I suspect it is the problem.

My questions are:

1. Are there other problems that could either cause the same symptoms?

2. How do you discharge the capacitors on the inverter board? There is no HV capacitor listed on the parts list, and I haven't seen one inside the microwave.

3. Are there any other parts I should test before putting in the inverter board?

Model number is GH5184XPS, sorry about that.

I plugged it into another circuit, but now the fuse inside the machine is blown, and it's completely dead.

Check the monitor switch (#10 on the diagram) and both interlock switches.

It's still missing one digit in the model number after "S".

Gene.