What we call Parts-Changing Monkeys (PCMs) around here at Appliantology are techs who rely on pattern recognition, tech myths, and blind luck to make their repairs. Case in point with this example of a GE ZGU385 gas cooktop, where said PCM figured he would get lucky by replacing a couple of components that seemed related to the problem, apparently without any troubleshooting beforehand.
Spoiler: he didn't get lucky.
Real technicians don't rely on luck to get things fixed. We rely on knowledge and the skillful application of that knowledge to troubleshoot and identify the problem. As the Samurai shows in this video, a professional technician can solve this problem using a systematic troubleshooting approach. All it requires is a basic understanding of electricity and the willingness to take the time to study the circuits and technology you're dealing with.
Watch and learn...