The machine has a self diagnostic system and if it finds a fault with a component the control panel shuts down and the number of seconds it takes to shut down indicates which component is faulty. Unfortunately I dont know what the 15 second error shutdown indicates but just wanted to tell you of the system so you dont change the control panel and the new one shuts down after 15 seconds as well. 3 seconds is high voltage inverter board fauty, 23 seconds is magnetron faulty Cheers
Kenjo
July 2012
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