EXITING HWY 71 EAST BOUND TO WOODWARD DECREASING SPEED THE VEHICLE IN FRONT OF ME HAD A CAR CUT IN FRONT OF HER. I HAD A SAFE DISTANCE AND SLAMMED MY BRAKES. MY BRAKES DID NOT GRAB AS USUAL MY CAR DID NOT STOP AND I HIT THE VEHICLE IN FRONT OF ME. I TRULY BELIEVE MY BRAKE SYSTEM FAILED. I WILL TAKE MY CAR INTO KIA WHEN I GET IT BACK.