What was found
DURING CLIMBOUT AIR SYSTEM 3 OFF ILLUMINATED WITH THE BLEED AIR 3 MANIFOLD ANNUNCIATOR LIGHT ON OVERHEAD PANEL ALSO ILLUMINATED. DURING DESCENT AIR SYSTEM 1 OFF ILLUMINATED. NO FUEL DUMPED AND ACFT RTB (MIA) WITH NO INCIDENT. PERFORMED FIM 36-23-03. REMOVED AND REPLACED MANIFOLD FAILURE CONTROL IAW MD11 AMM 36-23-01, OP CHECK NORMAL- NO FAULTS. PERFORMED FIM 36-11-01. RE-SECURED LOOSE UNION AT NR 1 HIGH STAGE VALVE AND RE-SECURED SENSE LINE IAW MD11 AMM 36-11-03, OP CHECK PASSED WITH NO FAULTS. RE-SECURED PACK COMPRESSOR DISCHARGE DUCT CLAMP IAW MD11 AMM 21-53-01, OP CHECK WITH NO LEAKS NOTED. PERFORMED PNEUMATIC SYSTEM PRESSURE DECAY CHECK WITH ENGINES NR 1 AND NR 3 IAW MD11 AMM 36-00-02 AND AMM 71-00-00. NO FAULTS NOTED. PERFORMED PNEUMATIC SYSTEM ADJUSTMENT/TEST IAW MD11 AMM 36-00-03, AMM 71-00-00, AND AMM 36-10-02. ALL PASSED WITH NO FAULTS.