What was found
ETOPS SIGNIFICANT SYS - LT DUCT LEAK LIGHT ILLUMINATED, EXTINGUISHED AFTER ENGINE BLEED SUPPLY AND ISOLATION VALVES CLOSED. ACCOMPLISHED FIM 26-18-00 WING DUCT LEAK DETECTION BITE, NO FAULTS NOTED. SYS CHECKED GOOD, OPS NORMAL. ACCOMPLISHED FIM 36-10-00,M NO LEAKS NOTED IN PNEU. DUCT FROM LEFT ISOLATION VALVE TO LEFT ENGINE PRSOV, NO FAULTS NOTED. ACCOMPLISHED AIR SUPPLY DISTRIBUTION SYS LEAKAGE TEST IAW AMM 36-11-00. LEAKAGE TESTED WITHIN LIMITS. LIGHTS & EICAS MESSAGES CLEARED. OK FOR SERVICE.