Downloaded service manual, got over my fear of getting shocked. Found Samsung put bleed resistors in capacitor, jumped with screwdriver to confirm as per service manual. Tested diode, found a large voltage drop with 9v battery. Capacitor test failed. Called into APP to confirm, got some great advice. Ordered cap and diode, arrived next day, installed and corrected problem. This micro has conv and is built into my motorhome, I had few options, none really, but to fix and no one wanted to touch it... Under $50 and back in business.