What was found
ON TAXI OUT, OBSERVED POWER BRAKES CIRCUIT BREAKER TRIPPED WITH MASTER CAUTION AND ANTI-SKID INOPERATIVE ANNUNCIATORS ILLUMINATED. RAN ANTI-SKID INOPERATIVE ABNORMAL CHECKLIST AND RETURNED TO RAMP. NO BRAKING AFTER CAUTIOUSLY MOVING FWD AND HAD TO USE EMERGENCY BRAKING SYS TO STOP. THERE WERE NO ANTI-SKID BITE INDICATORS TRIPPED AND NOTHING ABNORMAL NOTED WITH THE BRAKE LINES, BRAKE RESERVOIR, OR AFT J BOX. BLED BRAKES, SERVICED GEAR & BRAKES BOTTLE, CHECKED ALL ANTI-SKID MOTOR WIRES CHECKED OK, CHANGED ANTI-SKID MOTOR IAW AMM 32-42. OPS CHECKED NORMAL.