Pulled out oven and microwave combo from the cabinetry. Remove side rails in the front. Remove oven door for ease of movement. Be sure to support oven well. Carefully remove cover of microwave on right hand side (will need a small torx driver to remove screws on inner cover). Discharge capacitor with well insulated screw driver (DO NOT DO IF YOU DON'T KNOW WHAT YOU ARE DOING). Need another torx driver, slightly larger, to remove the magnetron. Magnetron easy to remove and install but time consuming to get to. Fixed the problem.