72168280790 Kenmore Range

Removed each switch (3) and checked them with multi-meter; got intermittent readings on two of the three. Also broke of a piece of the frame that holds the switches trying to remove them (old, exposed to heat and moisture over the years caused the plastic to become brittle and the wiring connectors were also hard to disconnect probably be ... Read more cause of heat and moisture over the years).
Went to PartSelect web site and discovered the three switches and frame were bundled in to one part number, 43501A. So, I called and spoke with a very knowledgeable technician and she explained why plus helped me order the part over the phone. When I received the part, the switches were already mounted in the frame and the frame was modified compared to the OEM frame. As I began to remove the old frame, I discovered why the new frame was modified. It was as if PartSelect had done many of these door interlock repairs and they knew exactly where and how to modify the frame and communicated this with the manufacturer, because the new frame installation was very easy, there was nothing hard about installing the new frame with the switches already in place. I then reconnected the wiring to the switches and tested the microwave and it works fine now, Problem solved, Thanks PartSelect.com

Initial failure of over range microwave Aug 3rd. Control Panel worked but no heat. Took to local LG authoriaed local repair place. They fixed it quickly and we re-installed it. Worked fine for 2 months then had similar failure again. Agaim took to same authorized repairer. They kept unit for 3 months but finally concluded theu could not ... Read more fix it and suggested we contact LG for a partial refund. When they tested the unit during re-assembly in my presence, there was a blue flash and the fuse blew. Since we had built a custom tile mural back splash around this unit, I brought it home, ordered a number of time delay fuses new capacitor and two new high voltage diodes. However, using my Fluke DMM, I checked the existing capacitor and high voltage diode and they checked OK so I just replaced the time delay fuse. The high voltage transformer leads had 2 possible ways to connect to capacitor and diode. Tried one way, plugged unit in and turned it on, and immediatly blew the fuse. Replaced the fuse and reversed the high voltage transformer connections,amd turned unit pn, and it worked perfectly. Since we had experienced several power failures during the time of the original failure, the repairer concluded that power spikes might be at fault, so I also purchased a TrippLite ISOBAR4ULTRA 3300 Joule surge protector between wall outlet and microwave, and re-installed over range. It has worked perfectly since.

Make sure 110v at the transformer. Activate switch controlled by the push button to open and close door. Push in the small metal arm on the switch with none metallic probe. If power is restored to microwave the switch is faulty and need replacement. One switch is not available, the whole 3 switch assemble has to be purchased.