PRESSED BRAKE PEDAL AND BRAKES DID NOT APPLY CAUSING VEHICLE TO STRIKE ONCOMING TRUCK CAUSING DAMAGE TO LEFT FRONT SECTION OF VEHICLE. VEHICLE CONTINUED TO ROLL WHILE BREAKS WERE PRESSED AS HARD AS POSSIBLE. OWNER OF VEHICLE HAS HAD PRIOR PROBLEMS WITH BREAK SYSTEM WHICH HAVE BEEN WORKED ON FOR PREVIOUS OTHER PROBLEMS BY DEALER WHERE VEHICLE WAS PURCHASED.