What was found
GIG - FLT 904 - DURING CLIMB-OUT AT FL280, NR 1 ENGINE FIRE STATUS MESSAGE ILLUMINATE. CREW RAN CHECKLISTS AND RETARDED NR 1 ENGINE AND STATUS MESSAGE QUIT. STATUS MESSAGE WAS INTERMITTENT WHILE DUMPING FUEL. FLIGHT RETURNED GIG AND LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE ACCOMPLISHED REQUIRED CHECKS AND PLCARDED NR 1 ENGINE FIRE LOOP. DURING OVERNIGHT MAINTENANCE, NR 1 ENGINE FIRE LOOP DETECTION FAULTED DURING TEST. REPLACED NR 1 ENGINE FIRE LOOP HARNESS. REQUIRED CHECKS PRODUCED NO FAULTS. PLACARD WAS REMOVED AND MIC SHEET CLEARED. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)