My over the range Whirlpool microwave will start like it should after pushing a quick start button or program button, then after two seconds it will shut off - everything except the timer which counts down two seconds and then everything will come back on and complete the cycle. After a couple of cycles like this, the unit will go into an on off on off mode. I had a fellow look at it yesterday and he suggested the microcomputer or one of the inverters. Where should I start??:confused:

Thanks for your help, Doug