Changed the internal fuse and the thermal fuses but still nothing. Also changed upper door switch still nothing. Went on line but could not find anything that matched my symptoms. Got some advice from one of those web sites. I needed to take it to a professional. It seemed to me one of the major components had failed so II went for the magntron. Now I had power everthing worked except the micro wave its self. Researched on line and came up with the lower door switch which I already had same as the upper so I tried that and low and behold it worked. Micro wave works 4.0. Hope this will help someone else who has the same problem. Remember safety when doing this repair can kill you.