I WAS ENTERING A LEFT HAND CURVE WITH THE BRAKE APPLIED. THE ROAD WAS A LITTLE ROUGH AND AS I APPLIED THE BRAKE HARDER, THE PEDAL WENT TO THE FLOOR. I PUMPED THE BRAKES, BUT THE CAR SLID OFF THE ROAD AND INTO THE DITCH STOPPING AGAINST THE BANK OF THE DITCH AND A POLE. IN THE PAST 12 MONTHS THE ABS WARNING LIGHT HAD COME ON SEVERAL TIMES, BUT HAD NOT STAYED ON THE NEXT TIME THE CAR WAS STARTED.