Same problem as above. NN SD968S 2.2 cuft micro. Powers on for 2 seconds with light, no fan or noise, then a relay click and the unit shuts off and clears the clock time. Someone suggested that would be the upper interlock switch. Usually there is an upper and lower switch held in a plastic housing so that both door levers proturde and engage/depress the switches at the same time when the door is closed. The housing on mine is held to the frame with 2 screws. At first, did not notice anything like a burnt contact, but I decided to take the 2 wires off and it was only then I noticed that the plastic around teh bottom contact had completely melted and the metal contact actually shifted. I am glad these things do not catch fire! Anyways, I'm still trying to source one, but it looks to cost only a couple bucks. Good luck with yours. The magnetron and inverter boards are usually pretty long-lasting. check the switch first!