One critical human factor that can jeopardize ship safety is failing to address known problems. Troubleshooting abilities are crucial for marine electrical engineers and electro technical teams, yet this capacity is typically developed gradually through field experience. Recent technology provides significant opportunities for creating advanced educational media in maritime education, such as full mission simulators for navigational training. However, its application in electrical troubleshooting remains limited. Serious games allow students to gain experience in troubleshooting without concern for safety or system damage, which is also flexible and accessible from any location. This article proposes a representation of real-world troubleshooting involving multiple locations through a serious game simulator. The presented design framework facilitates clear communication between educators, experts, and game developers, especially for structured multi-location scenarios. As proof of work, an earth fault troubleshooting game was developed using Unreal Engine 5, and tested on 40 marine electrical engineering students, significantly improving test scores (t statistic: 2.242, p value: 0.031). In addition, the most significant impact is interest in further learning, which scores 4.4 out of 5, reflecting increased knowledge and confidence. These results underscore the potential of serious games for marine electrical engineering and broader maritime education and training applications.