I have a Kenmore Microwave model 721.80012401 that is not heating. Everything else works and there aren’t any wierd noises. research on this site tells me to replace magnetron and/or diode, could it be anything else before I order the parts? do i need to go through sears only?
Open the control panel, remove the wires from the high voltage transformer primary windings and check for 120 VAC between these wires with the door closed and control calls for heat.
If there is 120 VAC then the magnetron has to be replaced.
If there is no 120 VAC then the control board probably has gone bad.
This microwave made overseas and all parts go through Sears only.