What was found
RECEIVED 4 TRANSIENT ECAM GREEN HYD PR LO INDICATION DURING TAXI, WHICH ALSO CAUSED AN AUTO-BRAKE SYSTEM TO FAILURE. ANALOG AND ECAM GREEN HYD PRESSURE AND QUANTITY BOTH SHOWED GOOD WHILE ECAM MESSAGE WAS DISPLAYED. HAD TO ABORT T/O DUE TO SECOND INDICATION. REMOVED AND REPLACE GREEN HYD PRESSURE SWITCH 30WW PER AMM 31-53-51-04 OP AND LEAK CHECK GOOD. REPLACED SDAC PRECAUTIONARY DUE TO ONLY ECAM ALERT AND ALL OTHER INDICACTIONS NORMAL PER AMM 31-55-22-04 OP CHECK GOOD. PERFORMED ENGINE STATIC RUN PER JRH. NO FAULTS AND ALL IDICATIONS NORMAL.