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Hi Folks, I could really do with a bit of help in diagnosing a Bosch microwave issue The model is: HBC86P753B/01 Combi Oven and Microwave. https://i.pinimg.com/originals/5d/7b/5d/5d7b5dd4a9d9cec46429852d96d23147.jpg The problem only affects the microwave section: The symptoms are as follows: I power on and select microwave at any power level setting, adjust timer to 1 minute and press start, The light comes on fan runs for about 3 seconds and then display resets back to clock. I am electronically qualified and aware of the high voltage risks, so dismantled to investigate yesterday. Magnetron shows no evidence of cracked magnets or distorted structure. Measures just under 1 ohm across heater with no leakage between either of the heater terminals and the case. If I run with the cover off, there are no sparks, unusual sounds or smells of burning. The conventional oven responds correctly to door switch when opened. This model uses an inverter PCB rather than the traditional capacitor and diode arrangement, so wondered if this module could be the cause. As the part is quite expensive, I thought it would be sensible to seek advice first. Are there any other items to check, or has anyone experience of this module failing? https://www.partmaster.co.uk/control-unit/product.pl?pid=1492093&query=HBC86P753B Many Thanks Regards Mike