As per the code tested temp sensor, you'll need a multimeter for this. It was okay. Ordered new circuit board and installed it. That canceled the code, but still wouldn't heat up. Called app.com and they suggested the temp fuse. Ordered one and it was delivered promptly, installed and we are back in business. Easy install on both parts.except for manhandling the oven outta the wall. I want to add that everywhere I searched the circuit board was 'obsolete'. This part was factory back ordered for app.com ,but the wait was short, approx. 10 days. The communication was excellent during the process. Good service,polite and prompt. Would use em again.