As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AT 5000 CABIN ALTITUDE AND AIRCRAFT ALTITUDE MET. CABIN CONTINUED DOWN AT SAME RATE AS A/C. WE SWITCHED TO AUTO 2 AND NO CHANGE. WE SWITCHED TO MANUAL AND REGAINED CONTROL OF CABIN RATE. REPLACED AUTO 1 CABIN PRESSURE CONTROLLER AND COCKPIT CONTROL PANEL IAW AMM 21-31-02 AND AMM 21-31-01.