As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WOULD NOT PRESSURIZE AFTER TAKEOFF. CABIN PRESSURIZATION WENT INTO FULL NEGATIVE RATE OF CLIMB. FLIGHT RETURNED TO MEM AND LANDED WITHOUT INCIDENT. MAINTENANCE FOUND FAULT WITH CABIN PRESSURE CONTROLLER. REPLACED CONTROLLER AND REPLACED CABIN PRESSURE AMPLIFIER AS A PRECAUTION. OPERATIONAL CHECK NORMAL ON GROUND.