What was found
EN ROUTE ORD-LHR, FAILURE OF BOTH AUTO-PRESSURIZATION CONTROLLERS. CREW ELECTED TO DIVERT TO JFK. *S/D* AT JFK, NO EXISTING FAULTS WERE FOUND. MAINTENANCE ACCESS TERMINAL GROUND TEST ON CABIN PRESSURE CONTROL WAS PERFORMED PER AMM 21-31-00. PRESSURIZATION SYSTEM PASSED OPERATIONAL CHECK. AIRCRAFT WAS RETURNED TO REVENUE SERVICE WITHOUT FURTHER INCIDENT. THE QAR (QUICK ACCESS RECORDER) CONTAINING DATA FROM THE AIRPLANE CONDITION MONITORING SYSTEM WAS SENT TO BOEING FOR FURTHER ANALYSIS.