This document describes an IoT-based system for detecting and locating faults in underground cable lines. The system uses a potential divider network laid across underground cables to detect faults. When a fault occurs, it generates a specific voltage that is sensed by a microcontroller. The location of the fault is determined by the voltage and corresponding distance in the resistor network. The microcontroller displays fault data on an LCD and transfers it online using ThingSpeak. This allows authorities to monitor cables and locate faults remotely via the internet. The system aims to quickly and easily detect fault locations without having to manually inspect the entire underground line.