What was found
L ENG BLEED OFF AND L PACK OFF EICAS LIGHT AND L ENG OFF (PNEUMATIC) VALVE LIGHT AND PACK OFF OVERHEAD LIGHT. C/X MC 227 AND CYCLED L ENG BLEED VALVE. AT 85% N2 AND VALVE NEVER OPENED, TOLD BY MAINTENANCE CONTROL TO RETURN TO THE GATE T/S AS PER FIM. 36-20 FT 804, FOUND PRVC CONTROLLER INOP. REMOVED / REPLACED PRVC IAW AMM 36-11-19, ALSO FOUND #1 LH PRV FLEXIBLE HOSE LEAKING REMOVED AND REPLACED #1 ENG PRV FLEXABLE HOSE AS PER AMM 36-11-18, LEAK CHK GOOD. IDLE RUN #1 ENG PER AMM 71-00-00. NO ENG BLEED OFF OR EICAS MESSAGES. A/C REMIANS NO ETOPS RETUNED AC TO SERVICE