MY WIFE WAS IN STOP AND GO TRAFFIC ON THE HIGHWAY AND THE BRAKES FAILED TO WORK, AND SHE REAR-ENDED THE VEHICLE IN FRONT OF HER. WE WENT TO THE HYUNDAI DEALERSHIP NEARBY AND THEY TESTED IT FOR TWO DAYS AND COULD NOT REPLICATE THE ISSUE. ON ONE OF THEIR TESTS THE ENGINE DIED AND THE BRAKE SYSTEM FAILED BUT THEY HAD NOT YET HOOKED UP THE DIAGNOSTIC EQUIPMENT SO THEY NEVER CAPTURED THE SOURCE OF THAT FAILURE. ALL OTHER TIMES THE BREAKS AND THE ENGINE WORKED FINE. THE RESULT WAS THAT THEY CANNOT DIAGNOSE THE PROBLEM.