IOWA CITY, Iowa -- You know your blood-alcohol content is too high when a Breathalyzer can't calculate it. Iowa City police said that's what happened early Friday morning when they gave a breath test to an Iowa City man that initially read .467 percent before reading "HI." Officers were called to 2105 J St., the home of 28-year-old Levi B. Carter, for a report of a man who drove off the road and hit a street sign. Police spoke with a passenger in Carter's vehicle who said they heard Carter slurring his speech and believed him to be drunk. The passenger also told police Carter was driving 55 mph on First Avenue - a 25 mph zone - before crashing his car. Police said Carter was talking to people in his basement who were not there, smelled strongly of alcohol and could barely stand without holding himself up. Carter allegedly told police he drank two Bud Lights and admitting to driving home. Carter failed an eye test and was too drunk to complete any other field sobriety tests. The .467 percent reading came on a weak test before the testing instrument simply read "HI," police said. Carter was arrested for drunken driving.