The CPU inside your Sharp microwave oven controls the cooking program, timer, carousel and all input from the control panel. A problem with the CPU can cause the oven to malfunction, preventing you from cooking or reheating your food. You can reset the CPU or cancel the current program to try and clear the problem. CPU errors are commonly caused by a power surge or software problem when entering instructions into the control panel.
Tap the "Stop/Clear" button a few times. This cancels the current program and clears any erroneous input confusing the CPU. Re-enter your cooking instructions and press the "Start/Minute Plus" button. The cook cycle won't begin until you press the "Start" button.
Ensure the CPU isn't in lockout mode. Sharp microwave ovens prevent children or unauthorized people from using the CPU with a lock feature. Press the "Clock" button, followed by "1," then hold "Start" for three seconds. "SAFE" appears on the screen once the microwave CPU is activated. Repeat these steps to restore the child lock.
Press "Clock," then "0," then hold "Stop/Clear" for three seconds. Demonstration mode is designed to show off the oven's features while the appliance is on display in the store. You won't be able to cook food while demo mode is running, although the oven will light up and hum.
Disconnect the microwave from the power supply for a minute. The CPU could be scrambled by a power surge or fault while you're entering information into the control panel. Plug the CPU back in after a minute. The LCD display will light up and the CPU should work again.
Jon Stefansson has been a professional writer since 2009. He is currently freelancing as an advertising and web copy writer for several Canadian and American clients. Stefansson graduated from Staffordshire University, England, with a Bachelor of Arts in broadcast journalism. He has freelanced for several British radio stations as a news reader and sports producer.