What was found
AC EXPERIENCED A FALSE FIRE WARNING ON THE LT ENGINE ENROUTE. WHILE FLYING THROUGH HEAVY PRECIPITATION. THE PILOT VISUALLY CHECKED THE ENGINE AND MONITORED ALL RELATED INSTRUMENTS AND SYSTEMS TO VERIFY NORMAL INDICATIONS THUS CONCLUDING THE INDICATION WAS FALSE. THE PILOT NOTIFIED MAINT UPON ARRIVAL. MAINT EXAMINED THE FIRE DETECTOR SYSTEM AND FOUND 2 WIRES CHAFING AT THE LT NACELLE AFT UPPER DETECTOR. THE MECHANIC REPOSITIONED AND REPAIRED THE WIRES IAW STANDARD MAINT PRACTICES AND OPERATIONALLY CHECKED THE SYSTEM. NO DEFECTS WERE NOTED. THE MECHANIC ALSO INSPECTED THE ENGINE FOR VISIBLE SIGNS OF FIRE. NONE NOTED. (K)