As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE PURPOSE OF THE TWO EXTINGUISHING VALVES IS TO LEAD BY MEANS OF ITS COORDINATE ACTION, THE DISCHARGE OF EXTINGUISHING AGENT TOWARDS THE DESIRED ENGINE. NR 1 ENG VALVE DISK WAS FROZEN ON SHAFT. NR 2 ENG VALVE DISK WAS PREVENTED FROM SEATING DUE MILD CORROSION. RECOMMEND: FREQ BE CHANGED FROM EVERY 6 YEARS TO 1 YEAR FOR FUNCTIONAL TEST OF SYSTEM.