What was found
RETURN TO FLIGHT DUE DURING CLIMB HAD PRESSURIZATION FAILURE. AIRCRAFT RETURNED OF FLIGHT DUE TO DURING CLIMB, IT WAS HAD A PRESSURIZATION FAILURE. MAINTENANCE PERSONNEL PERFORMED REVISION TO LEFT PRESSURIZATION CONTROLLERS, NO SHOWING FAILURE CODE; COPY FLIGHT DATA RECORDER DOWNLOAD WAS PERFORMED IAW AMM 31-31-00-970-808 AS REQUESTED BY SEGA; OPERATIONAL TEST PRESSURIZATION SYSTEM WAS PERFORMED IAW AMM 21-31-00-710-801 AND CABIN PRESSURE LEAK TEST WAS PERFORMED IAW AMM 05-51-91-790-801, TESTED CORRECT.