What was found
CREW REPORTS THAT THEY RECEIVED A FIRE SYSTEM FAULT STATUS MESSAGE CAME ON DURING CRUISE FLIGHT AND WENT OUT ON DESCENT. MAINTENANCE INSPECTED THE AIRCRAFT AND INTERROGATED THE MDC. THE MDC REPORTS THE RT ENGINE LOOP HAS AN INTERMITTENT SHORT CIRCUIT. THE SYSTEM WAS PLACED ON MEL. REPORT TO REMAIN OPEN PENDING FURTHER INFORMATION. PERFORMED THE PROCEDURE IAW THE FAULT ISOLATION MANUAL AND PERFORMED OPERATIONAL CHECKS OF THE FIDEX SYSTEM. ALL CHECKS WERE GOOD AND NO FAULTS WERE NOTED. THE AIRCRAFT WAS RETURNED TO SERVICE.