What was found
ON CLIMB OUT OF PHX EN ROUTE FOR YVR YELLOW HYDRAULIC OVERHEAT INTERMITTENTLY FLASHED ON HYDRAULIC PAGE, TURNED BACK TO PHX. MAINTENANCE REMOVED AND REPLACED THE NR 1 SYSTEM DATA AQUISITION CONCENTRATOR (SDAC) IAW AMM 31-55-34, OPERATIONAL CHECK WAS GOOD. MANUFACTURER RECOMMENDED REPLACEMENT OF WIRE ASSEMBLY (P/N LA1E50200HW0100), INPUT BOARD (P/N LA1E50100H3320C, AND INPUT CONVERSION BOARD (P/N LA1E50100H3310A). PARTS WERE REPLACED AND UNIT WAS TESTED IAW CMM 31-55-44, REV. 3.