As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMB AIRCRAFT DID NO PRESSURIZE. TRIED MANUAL PRESSURIZATION. DID NOT WORK. RAN QRH PRSN AUTO FAIL CHECKLIST. RETURNED TO DFW DID NOT DECLARE EMERGENCY.-C/A-RAR GROUND CONNECTION VALVE COVER IAW AMM 21-22-04.PERFORMED OPERATIONAL CHECK FOR PRESSURIZATION IAW AMM 21-31-00, IN AUTO AND MANUAL MODES.OPC GOOD. NO DEFECTS NOTED.