I have a GE Monogram ZET2PH1SS. Yesterday the following started.

If both ovens are cool everything appears ok and the lower over will start up fine. If I start the upper over, once it reaches around 300 for a few minutes the mode selector knob for the lower over lights up and there is a short buzz. At this point if you try to set the lower oven to do anything you get a short buzz. Turn everything off and once the upper over cools below about 200 the lower oven mode knob light goes off, It usually goes off then back on a few times as it cools down. Once the upper cools enough the lower seems to work fine again.

There are no error codes. Only the lower mode selector lighting up and the short buzz.

I have tried resetting from the user menu and have cut power for a couple of minutes and turned back on.

Thanks,
Bob