TL*THE CONTACT WAS RENTING A 2003 FORD WINDSTAR. WHILE DEPRESSING THE BRAKE PEDAL, THE VEHICLE WOULD NOT STOP. THE CONTACT NOTICED SMOKE AND THE BRAKE WARNING LIGHT ILLUMINATED ON THE INSTRUMENT CONTROL PANEL. SHE HAD TO APPLY PRESSURE TO THE BRAKE PEDAL SEVERAL TIMES IN ORDER TO STOP THE VEHICLE. SHE CALLED THE RENTAL COMPANY AND THEY STATED THAT THERE WAS NOTHING WRONG WITH THE BRAKE SYSTEM. THEY CONCLUDED THAT THE BRAKE SYSTEM POSSIBLY NEEDED TO BE SERVICED. THE VIN AND SPEED WERE UNKNOWN. THE FAILURE MILEAGE WAS 62,221.