J B Brockport , NY October 02, 2015 Appliance: Samsung Microwave SMH9187W/XAA Samsung Microwave Smh9187w/Xaa / : Se code and unit inoperative. How to replace Microwave Touch Control Membrane Switch. "short error" replacing the keypad seems to have fixed it. It's logical that over time the plastic in the keypad would break down and the space between contacts gets smaller. It has been a week with the unit on and working fine. Do-It-Yourself Rating: Repair Time Estimate: 15-30 minutes