What was found
EN ROUTE QPG TO OKO, THE NR 3 ENGINE FIRE WARNING LIGHTS ILLUMINATED. CREW SHUT THE ENGINE DOWN AND SEQUENCED THE FIRE BOTTLE FOR THAT ENGINE ON A PRECAUTIONARY BASIS. AIRCRAFT RETURNED QPG WITH AN UNEVENTFUL LANDING. MAINTENANCE INSPECTED THE ENGINE FOR EVIDENCE OF A FIRE, NO EVIDENCE WAS FOUND. MAINTENANCE REPLACED THE FIRE BOTTLE, FIRE DETECTOR AMPLIFIER AND CLEANED THE FIRE DETECTOR CONNECTORS. A SUCCESSFUL ENGINE RUN WAS COMPLETED AND THE AIRCRAFT WAS RETURNED TO SERVICE. (M)