Edward P Sebastopol , CA September 21, 2018 Appliance: Samsung Microwave SMH9187ST/XAA Samsung Microwave Smh9187st/Xaa / : S5 error code on microwave. How to replace Microwave Control Panel Assembly. Went on line and googled the code, found a utube video that explained pretty much how to correct the problem but also suggested that it could be temporary and the best way was to replace the touch pad assembly. Ordered the unit and installed it in about 30 minutes and has been working fine ever since. Do-It-Yourself Rating: Repair Time Estimate: 15-30 minutes