What was found
ACFT DIVERTED DUE TO DUAL ENGINE BLEED FAILURE. DESCENDED TO 10,000 FEET AND APU WAS STARTED TO MAINTAIN CABIN PRESSURIZATION. EMERGENCY WAS DECLARED, PERFORMED RAPID DESCENT PER QRH TO 10,000, MASKS WERE DONNED IN FLIGHT DECK, NO MASKS DEPLOYED IN CABIN, CABIN REACH APPROXIMATELY 10,500 MSL. REPLACED LEFT ENGINE FAN AIR MODULATING VALVE, FAN AIR TEMP SENSOR, PRESSURE REGULATING SHUTOFF VALVE, REVERSE FLOW CONTROLLER, HIGH STAGE REGULATORS, AND REPLACED OVERHEAD PNEUMATIC CONTROL PANEL. BOTH ENGINE BLEEDS NOW CHECK NORMAL. ACFT RETURNED TO SERVICE.