What was found
THE NR 2 PNEUMATIC SUPPLY TEMP HIGH LIGHT ILLUMINATED DURING CLIMBOUT OF FRA NR 1 PNEUMATIC SYSTEM WAS PLACARD INOPERATIVE. THE NR 2 PNEUMATIC SUPPLY WAS SHUT OFF AND THE LIGHT EXTINGUISHED. FUEL WAS DUMPED AND THE AIRCRAFT WAS RETURNED TO FRA WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND THE NR 2 FAN AIR VALVE AT FAULT. THE FAN AIR VALVE WAS REPLACED. AN ENGINE POWER ASSURANCE RUN WAS PERFORMED AND ALL TEMPERATURE INDICATIONS WERE NORMAL.