What was found
L DUCT LEAK LGT ILLUM, EICAS MSG BLD DUCT LEAK DISPLAYED, LGT EXTINGUISH AFTER ENG BLEED AIR SUPPLY AND ISOLATION VALVES CLOSED. PERFORMED PNEUMATIC DUCT FLEXIBLE BALL JOINTS INSPECTION IN ACCORDANCE WITH AMM 36-11-01 FOUND 1 OF 5 FLEXIBLE JOINT LOOSE. RETIGHTEN IN ACCORDANCE JOB CARD. ALSO PERFORMED WING AND BODY DUCT LEAK DETECTION BITE PROCEDURE. IN ACCORDANCE WITH 26-18-00 BLOCK 6. ALL DUCTS INTEGRITY FROM ENGINES TO ISOLATED VALVE AND APU LEAK DETECTOR ELEMENTS. FOUND WITH LIMITS (LESS THAN 1 MEGOHM). RUN ENGINE AND NO FAULT NOTED. ANTI-ICING SYSTEM CHECK DUE OBVIOUS LEAKS, OK.