CONCERN: Customer reports microwave is not working. DIAGNOSTIC AND CAUSE: Inspected power supply at the wall for 120V, voltage at supply line normal at time of inspection. Inspected control board for visible signs of shorts, no signs of shorts a the control board. Inspected microwave 20 amp safety fuse for shorts. Microwave fuse shorted. CORRECTION: Replaced microwave fuse and switch and tested, operation now normal.