What was found
FLIGHT 6255 - FLL-RIC - SHORTLY AFTER BEGINNING TAXI OUT, THE BRAKE PEDAL WAS DEPRESSED WITH NO BRAKE ACTUATION. THE BRAKE PEDAL WAS FULLY DEPRESSED AND APPROXIMATELY 5 SECONDS LATER, THE BRAKES ABRUPTLY FULLY APPLIED. THE AIRCRAFT WAS BROUGHT TO A COMPLETE STOP AND WAS TUGGED BACK TO THE GATE. THE EMERGENCY BRAKE FUNCTIONED PROPERLY AND A BRAKE DEGRADED MESSAGE APPEARED ON EICAS. MAINTENANCE FOUND A LOOSE CONNECTOR ON THE BRAKE CONTROL UNIT. RESECURED ALL CONNECTIONS AND TAXI CHECKED THE AIRCRAFT. TAXI CHECK AND OPS CHECK GOOD.