What was found
CABIN ALT WARNING AT FL250. CABIN PRESSURE LOST. WAS ON PRESS CONTROLLER 2 WHEN IT HAPPENED. FA REPORTED LITTLE TO NO AIRFLOW IN THE CABIN SHORTLY BEFORE THE CABIN ALT CAUTION CAME ON FOLLOWED BY THE WARNING MSG. (FLIGHT 3191 - FILED CLOSED) PLEASE REFERENCE AML 903587 PLEASE REFERENCE AML 903606 PLEASE REFERENCE AML 903610, REFERENCE FWD DISCREPANCIES FOR ALL PARTS INFORMATION. REMOVED AND REPLACED CABIN PRESSURE CONTROLLER #2 DUE TO #2 CPC BEING IN CONTROL DURING CABIN ALT WARNING MESSAGE. REMOVED AND REPLACED CABIN PRESSURE CONTROL PANEL DUE TO CABIN ALT WARNING MESSAGE IN FLIGHT. RE-CONNECTED LOW PRESSURE GROUND CONNECTION DUCT AND INSPECTED FUNCTIONAL OPERATION OF BUTTERFLY CHECK VALVE. INSPECTED ALL DEPLOYED O2 MASKS AND REPLACED DAMAGED MASKS AT APPLICABLE ROWS/SEATS.