As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MSN TO LAS - DURING CLIMBOUT AT 9000 FT CREW REPORTED FLOW LIGHT ILLUMINATED. CABIN CLIMBED 500 FT PER MINUTE WHILE LEVEL. COULD NOT MAINTAIN CABIN IN AUTO. CREW COMPLETED FLOW LIGHT ILLUMINATED CHECKLIST. AIRCRAFT RETURNED TO MSN AND LANDED WITHOUT INCIDENT. MAINTENANCE DEFERRED AUTOMATIC PRESSURE CONTROL IAW MEL 21-24. AIRCRAFT RETURNED TO SERVICE.