As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SHORTLY AFTER TAKEOFF AUTOFAIL LIGHT ON OVERHEAD PRESSURIZATION CONTROL PANEL ILLUMINATED. CHECKLIST ACCOMPLISHED AND OPERATED IN ALTN MODE. CB FOR AUTO CONTROLLER 2 IS POPPED GROUNDED YES. CONFIRMED FAULT. NR 2 AUTO MODE MOTOR ON OUTFLOW VALVE OPS C/B REF WDM 31 31 23. REMOVED AND INSTALLED NEW AFT OUTFLOW VALVE ASSY REF AMM 21 31 03 000 801. PERFORMED GROUND FUNCTIONAL CKS MAN MODE TEST REF MM 21 31 00 710 801 AND CABIN PRESSURE CONT SYS TEST REF MM 21 31 00 700 802 CK GOOD.