What was found
FLT 0823 - AT DECENT INTO PHX RECEIVED A BSCU CHANNEL NR 1 FAULT, & HYD BLUE RESERVOIR LOW AIR PRESSURE MESSAGE. DECLARED AN EMER, A/C LANDED W/O EVENT. MAINT CHECKED BLUE HYD SYS RESERVOIR QTY WHEN A/C ARRIVED AT GATE; RESERVOIR QTY GOOD. RESERVOIR AIR PRESSURE WAS AT 75 PSI. AS PRECAUTION R & R BLUE HYD RESERVOIR PRESS SWITCH, OPS AND LEAK CHECK GOOD. BRAKE SERVO VALVE FAULTED ON DISPLAY SYSTEM. REMOVED AND REPLACED BRAKE SERVO VALVE, OPERATIONAL & LEAK CHECK GOOD. BRAKE SERVO VALVE WAS NOT TESTED, UNIT WAS OVERHAULED AND RETURNED TO SERVICE.