The OP's microwave is an AC/DC unit same as mine but needs to see DC for AC to work, just finished fighting this demon 2 weeks ago, and the dealer is putting in my new converter this week. I finally had an electrician map out my unit as it was driving me crazy.
Some AC worked (second air unit), outside frig, outside microwave and other things would not work (main Air unit, inside frig, inside Microwave), it was nuts.
2011 GMC 3500HD 4x4 Crew DRW Duramax
2012 Sierra 365SAQ
2006 Police Roadking FLHPi