As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLIMBING THROUGH 5000 FEET, CAPTAIN NOTICIED ACFT NOT PRESSURIZING. LEVELED AT 10000 FEET AND RAN THE PRESSURIZATION FAIL CHECKLIST AND RETURNED TO FIELD WITH MANUAL CONTROL BUT IT DIDNT WORK CORRECTLY EITHER. ACCESSED CDS DATA FOUND CPC/OF VALVE DATA FAIL. ACCOMPLISHED FIM TASK 21-30-00-810-804. CAWP CABIN PRESS LT WAS NOT ON. DUE HISTORY REMOVED & REPLACED AFT OUT FLOW VALV PER AMM 21-31-16-000-801 & 21-31-16-400-801. OPS TEST OF PRESS CONTROL GOOD REF AMM 21-31-00-720-801 NO FAULTS MESSAGES CURRENTLY DISPLAYED ON CDS. RETURNED TO SERVICE.