What was found
ON SHORT FINAL INBOUND EDDF FROM KWI, THE NUMBER 4 ENGINE FIRE BELL SOUNDED AND THE FIRE WARNING LIGHT ILLUMINATED. CAPTAIN RESET MASTER FIRE WARNING SWITCH WHICH SILENCED THE BELL. THE LIGHT REMAINED ILLUMINATED FOR 3 TO 4 SECONDS AND EXTINGUSHED. AN UNEVENTFUL LANDING WAS ACCOMPLISHED. MAINTENANCE INSPECTED THE ENGINE FIRE WARNING WIRING AND FOUND A CHAFED WIRE ON THE UPPER LOOP CONTACTING A PNEUMATIC BLEED DUCT. THE WIRE WAS REPAIRED IAW DAC M/M CHAPTER 20. SYSTEM PASSED A SUCCESSFUL GROUND OPERATIONAL CHECK IAW DAC M/M 26-10-1.