Interior light and turn table did not function.
Dennis M. • Dawsonville, GA • April 08, 2014
Appliance: Model 721.63762
My Repair & Advice
Fortunately, I had found the schematic drawing of the microwave. I was able to deduce from the drawing that relay RY1 on the control board printed circuit was not functioning. Rather than try to find the replacement relay and then remove and replace it on the board, I opted for replacing the entire board. The cost of the board from Appliance Pro's was reasonable ($60). I think if I had a service do the repair it would have cost me around $200.
This repair is not recommended for the average DIY person. Requires knowledge of electronics and electrical components.