As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AUTO FAIL LIGHT ON PRESSURIZATION PANEL ILLUMINATED ON DESCENT. ALTERNATE FAILED TO TAKE OVER RIGHT AWAY. REGAINED CONTROL IN MANUAL AND THEN TRIED ALTERNATE AGAIN AND IT WORKED IN ALTERNATE. REMOVED AND REPLACED NR 1 PRESSURE CONTROLLER PER M/M. GROUND CHECKS GOOD PER M/M.