Abstract: ThisThis study investigates the phenomenon of energized exterior walls and electrical equipment enclosures in residential buildings. Through on-site inspections and assessments of grounding configurations in low-voltage circuits, combined with field measurement data, the root cause of the fault is identified as improper grounding scheme implementation in the low-voltage system and unauthorized modifications of electrical wiring by customers, which led to an expanded fault voltage. The fault diagnosis is further validated using Matlab. The fault analysis and troubleshoot method presented provide valuable insights for addressing common issues such as energized equipment enclosures and low-voltage in low-voltage distribution networks.