What was found
ON CLIMBOUT, RECEIVED ECAM WARNING FOR GREEN HYD SYS NR 1 ENGINE LOW PRESSURE AND FLUID QUANTITY. TURNED BACK TO PHX AND LANDED, TAXIED BACK TO GATE. MAINTENANCE REMOVED AND REPLACED THE NR 1 ENGINE (GREEN HYD SYS) ENGINE DRIVEN PUMP IAW AMM 29-11-51-000-010, LEAK CHECK WAS GOOD, BUT OPERATIONAL CHECK INDICATED FAULTS TQ 0085 AND TQ 0894. REMOVED AND REPLACED HYD PRESSURE SWITCH (1074GK), LEAK AND OPERATIONAL CHECK WERE GOOD IAW AMM 29-11-17. VENDOR BENCH TEST OF ENGINE DRIVEN HYD PUMP COULD NOT CONFIRM FAILURE. UNIT PASSED TO SPECIFICATIONS AS RECEIVED, PRESSURE SET AT 3025 PSI PER CMM 29-11-33.