What was found
PHX-COS - FLT NR 412 - AIR TURNBACK, LT AND RT ENGINE BLEED TRIP LIGHT ILLUMINATED DURING BLEEDS OFF TAKEOFF. LEFT BLEED TRIP RESET AFTER RELIEVING PRESSURE/TEMPERATURE BY ACTIVATING THE ASSOCIATED ANTI-ICE VALVES. RT ENGINE BLEED WOULD NOT RESET. AIRCRAFT RETURNED TO PHX AND LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE NR 2 ENGINE FAN AIR VALVE IAW MM 36-11-05, THE NR 2 ENGINE HIGH STAGE VALVE PER MM 36-10-05, THE NR 2 ENGINE HIGH STAGE VALVE PER MM 36-10-15, AND THE NR 2 ENGINE BLEED AIR REGULATOR PER MM 36-10-11. ALL OPS AND LEAK CHECKS GOOD. (M)