This study proposes a fault detection system for underground cables using a microcontroller and a global system for mobile communication (GSM). The microcontroller notifies the user remotely through GSM after identifying the location of a fault in the underground cable. This proposed system can investigate the presence of faults up to a predetermined distance. The system includes a display device that shows the distance at which a fault occurs. It uses the simple concept of Ohm’s law to trace fault location by calculating the value of line resistance. When a fault occurs short message service (SMS) will be sent to the program’s specified mobile number and displayed on the Liquid crystal display (LCD). This will allow technical crews to respond more quickly to these faults, perhaps saving transformers from damage. A GSM modem, an Atmega328P microcontroller, and an analogue to digital converter (ADC) circuit are used in the system. Finally, because the system automatically and reliably gives precise fault location information, the time necessary to find a fault is greatly reduced.