As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PHX - INFLIGHT TUS-ORD. CREW REPORTED MULTIPLE PRESSURIZATION FAULTS DURING CLIMBOUT. EMERGENCY DECLARED DIVERTED PHX LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED BOTH PRESSURIZATION CONTROLLERS AND PRESSURIZATION CONTROL PANEL. TIGHTENED THREE UNIONS AND B-NUTS ON LEFT AUGMENTATION VALVE THAT WERE LOOSE. SYSTEM GROUND CHECKED NORMAL OPERATION.