Cathy S Chesterland , OH April 13, 2021 Appliance: General Electric Microwave PEB1590SM1SS Ge Microwave Peb1590sm1ss: Fan and turntable turned on when door was opened. How to replace Door Interlock Switch. We removed the control panel and replaced a faulty Switch Primary Interlock. This was a built-in model, so it was not an easy fix. Also, it required a Torx Security bit. We found some helpful videos. Do-It-Yourself Rating: Repair Time Estimate: 1-2 hours