With the support of Appliance Parts Pros, I ordered 3 parts (plus glass stove top cleaner) that were suspected to be the cause of the problem for a total of $49.59. Easily replaced the Range Oven Sensor, $15.91, at the back of the interior oven & that was it! All oven features work fine & my wife set the oven for the clean cycle earlier today. So far, so good! Thanks for your help! Would recommend Appliance Parts Pros to anyone.