Our microwave oven is only about 18 months old. It has worked fine until last week when we came home to find it completely dead. There are no working lights, sounds, etc. The outlet is working, so I know that’s not the issue. Any guidance on where to even begin to diagnose the problem?
I’d start with checking the internal fuse.
Part 5022 in this diagram.
Parts for LG LMH2235ST: Interior Parts - AppliancePartsPros.com