As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE CREW EXECUTED AN EMERGENCY DESCENT DUE TO LOSS OF CABIN PRESSURIZATION. MASKS DID NOT DEPLOY. MAINTENANCE REPLACED THE CABIN OUTFLOW DRIVE ASSY IAW AMM 21-32. THE NR 2 CABIN PRESSURE CONTROLLER WAS REPLACED IAW AMM 21-32. THE FORWARD LT CABIN PRESSURE SAFETY VALVE WAS REPLACED IAW AMM 21-32 BECAUSE IT WAS FOUND OPEN DURING THE CABIN PRESSURIZATION CHECKS.