What was found
REJECTED TAKEOFF AT APPROX. 50 KTS, DUE TO MASTER CAUTION, ECAM, GPWS FAULT AND ECAM BRAKE HOT, MLG WHEEL NR 3 INDICATED 995 DEGREES, THEN AMBER XX, FIRE DEPT PERSONNEL MEASURED WHEEL 3 TEMPATURE AT 97 DEGREES F, WHILE STOPPED ON RUNWAY, FMGC 1 INDICATED INOPERATIVE. REMOVED AND REPLACED THE NR 1 FMGC . AIRCRAFT WAS GROUNDED.