As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR RETURN, FLIGHT 5141 ENROUTE, CABIN "ALTITUDE HIGH" ILLUMINATED AND NORMAL PRESSURIZATION APPEARED TO HAVE FAILED. MX CLEANED FILTERS ON THE CABIN PRESSURE RELAY AND CHECKED ALL REMAINING FILTERS FOR ANOMALIES IAW REF MM 21-30. GROUND OPERATIONAL TESTS OK.