As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LAX CREW REPORTED PRESSURIZATION PROBLEMS AND CABIN PRESSURIZATION LIGHT ILLUMINATED. EMERGENCY DECLARED FLIGHT RETURNED LAX LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED CABIN PRESSURE CONTROLLER ONE AND TWO, CIRCUIT BREAKER J2 AND RELAY R2-258. SYSTEM GROUND CHECK NORMAL OPERATION.